Angular Signals - Revolution in Angular development

Angular in the midst of change. Signals play a central role as a small revolution in the modern, new Angular development. This talk will dive into the world of signals, explain how they work and why they are revolutionizing Angular application development. We will explore the technical aspects and best practices for using Angular Signals effectively, and look at what an Angular application with Signals can look like. This talk is an essential resource for anyone looking to expand their knowledge of Angular development and fully utilize the power of Angular Signals.

Transcript

1. (R)evolutio
2. Why?
3. Optimized UI UPDATEs
4. Zoneless
5. No Unsubscribe
6. Interop with Rxjs
7. Signals Observables &&
8. What are Signals?
9. const todos = signal([]);
10. todos = signal<Todo[]>([]); todos(); todos.set(...); todos.update((items) => { /* ... */ }); 1 2 3 4 5 6 7
11. todos = signal<Todo[]>([]); todos(); todos.set(...); todos.update((items) => { /* ... */ }); 1 2 3 4 5 6 7 todos = signal<Todo[]>([]); 1 2 todos(); 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7
12. todos = signal<Todo[]>([]); todos(); todos.set(...); todos.update((items) => { /* ... */ }); 1 2 3 4 5 6 7 todos = signal<Todo[]>([]); 1 2 todos(); 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7 todos(); todos = signal<Todo[]>([]); 1 2 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7
13. todos = signal<Todo[]>([]); todos(); todos.set(...); todos.update((items) => { /* ... */ }); 1 2 3 4 5 6 7 todos = signal<Todo[]>([]); 1 2 todos(); 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7 todos(); todos = signal<Todo[]>([]); 1 2 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7 todos.set(...); todos = signal<Todo[]>([]); 1 2 todos(); 3 4 5 6 todos.update((items) => { /* ... */ }); 7
14. todos = signal<Todo[]>([]); todos(); todos.set(...); todos.update((items) => { /* ... */ }); 1 2 3 4 5 6 7 todos = signal<Todo[]>([]); 1 2 todos(); 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7 todos(); todos = signal<Todo[]>([]); 1 2 3 4 todos.set(...); 5 6 todos.update((items) => { /* ... */ }); 7 todos.set(...); todos = signal<Todo[]>([]); 1 2 todos(); 3 4 5 6 todos.update((items) => { /* ... */ }); 7 todos.update((items) => { /* ... */ }); todos = signal<Todo[]>([]); 1 2 todos(); 3 4 todos.set(...); 5 6 7
15. todos = signal<Todo[]>([]); count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); 1 2 3 4 5 6 7
16. todos = signal<Todo[]>([]); count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); 1 2 3 4 5 6 7 count = computed(() => todos().length); todos = signal<Todo[]>([]); 1 2 3 4 effect(() => { 5 console.log('Todos count changed to ', count()); 6 }); 7
17. todos = signal<Todo[]>([]); count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); 1 2 3 4 5 6 7 count = computed(() => todos().length); todos = signal<Todo[]>([]); 1 2 3 4 effect(() => { 5 console.log('Todos count changed to ', count()); 6 }); 7 effect(() => { console.log('Todos count changed to ', count()); }); todos = signal<Todo[]>([]); 1 2 count = computed(() => todos().length); 3 4 5 6 7
18. todos = signal<Todo[]>([]); console.log('Todos: ' + todos()); effect(() => { console.log('Todos', todos()); }); 1 2 3 4 5 6 7
19. Reactivity
20. Reactivity Context base o
21. // Reactive in TS effect(() => { console.log('Todos', todos()); }); // Reactive in HTML <div>{{ todos() }}</div> todos = signal<Todo[]>([]); 1 2 console.log('Todos: ' + todos()); 3 4 5 6 7 8 9 10 11
22. Live Consumers
23. Consumers
24. Consumers Producers
25. Consumers Producers Or Both!
26. Reactive Graph
27. https://github.com/angular/angular/blob/17.1.2/packages/core/primitives/signals/src/graph.ts#L36-L44
28. todos = signal<Todo[]>([]); effect(() => { console.log('Todos', todos()); }); 1 2 3 4 5
29. Signal Reactive Context
30. Signal Reactive Context todos() effect() / HTML
31. Signal todos() Reactive Context effect() / HTML
32. Signal todos() Reactive Context effect() / HTML
33. Push Pull
34. /** * Propagate a dirty notification to live consumers of this producer. */ export function producerNotifyConsumers(node: ReactiveNode): void { if (node.liveConsumerNode === undefined) { return; } // Prevent signal reads when we're updating the graph const prev = inNotificationPhase; inNotificationPhase = true; try { for (const consumer of node.liveConsumerNode) { if (!consumer.dirty) { consumerMarkDirty(consumer); } } } finally { inNotificationPhase = prev; } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
35. /** * Propagate a dirty notification to live consumers of this producer. */ export function producerNotifyConsumers(node: ReactiveNode): void { if (node.liveConsumerNode === undefined) { return; } // Prevent signal reads when we're updating the graph const prev = inNotificationPhase; inNotificationPhase = true; try { for (const consumer of node.liveConsumerNode) { if (!consumer.dirty) { consumerMarkDirty(consumer); } } } finally { inNotificationPhase = prev; } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 export function producerNotifyConsumers(node: ReactiveNode): void { /** 1 * Propagate a dirty notification to live consumers of this producer. 2 */ 3 4 if (node.liveConsumerNode === undefined) { 5 return; 6 } 7 8 // Prevent signal reads when we're updating the graph 9 const prev = inNotificationPhase; 10 inNotificationPhase = true; 11 try { 12 for (const consumer of node.liveConsumerNode) { 13 if (!consumer.dirty) { 14 consumerMarkDirty(consumer); 15 } 16 } 17 } finally { 18 inNotificationPhase = prev; 19 } 20 } 21
36. /** * Propagate a dirty notification to live consumers of this producer. */ export function producerNotifyConsumers(node: ReactiveNode): void { if (node.liveConsumerNode === undefined) { return; } // Prevent signal reads when we're updating the graph const prev = inNotificationPhase; inNotificationPhase = true; try { for (const consumer of node.liveConsumerNode) { if (!consumer.dirty) { consumerMarkDirty(consumer); } } } finally { inNotificationPhase = prev; } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 export function producerNotifyConsumers(node: ReactiveNode): void { /** 1 * Propagate a dirty notification to live consumers of this producer. 2 */ 3 4 if (node.liveConsumerNode === undefined) { 5 return; 6 } 7 8 // Prevent signal reads when we're updating the graph 9 const prev = inNotificationPhase; 10 inNotificationPhase = true; 11 try { 12 for (const consumer of node.liveConsumerNode) { 13 if (!consumer.dirty) { 14 consumerMarkDirty(consumer); 15 } 16 } 17 } finally { 18 inNotificationPhase = prev; 19 } 20 } 21 consumerMarkDirty(consumer); /** 1 * Propagate a dirty notification to live consumers of this producer. 2 */ 3 export function producerNotifyConsumers(node: ReactiveNode): void { 4 if (node.liveConsumerNode === undefined) { 5 return; 6 } 7 8 // Prevent signal reads when we're updating the graph 9 const prev = inNotificationPhase; 10 inNotificationPhase = true; 11 try { 12 for (const consumer of node.liveConsumerNode) { 13 if (!consumer.dirty) { 14 15 } 16 } 17 } finally { 18 inNotificationPhase = prev; 19 } 20 } 21
37. todos = signal<Todo[]>([]); effect(() => { console.log('Todos', todos()); }); 1 2 3 4 5
38. todos = signal<Todo[]>([]); effect(() => { if(false) { console.log('Todos', todos()); } }); 1 2 3 4 5 6 7
39. Live Consumers
40. count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); todos = signal<Todo[]>([]); 1 2 3 4 5 6 7
41. count = computed(() => todos().length); effect(() => { console.log('just a message'); }); todos = signal<Todo[]>([]); 1 2 3 4 5 6 7
42. Live Consumers Transitive
43. Signal todos() Reactive Context effect() / HTML computed()
44. Signal todos() Reactive Context effect() / HTML computed()
45. Signal todos() Reactive Context effect() / HTML computed()
46. Signal todos() Reactive Context effect() / HTML computed()
47. Signal todos() Reactive Context effect() / HTML computed()
48. Versioning
49. interface ConsumerNode extends ReactiveNode interface ProducerNode extends ReactiveNode export interface ReactiveNode { version: Version; lastCleanEpoch: Version; dirty: boolean; producerNode: ReactiveNode[] | undefined; producerLastReadVersion: Version[] | undefined; producerIndexOfThis: number[] | undefined; nextProducerIndex: number; liveConsumerNode: ReactiveNode[] | undefined; liveConsumerIndexOfThis: number[] | undefined; consumerAllowSignalWrites: boolean; readonly consumerIsAlwaysLive: boolean; producerMustRecompute(node: unknown): boolean; producerRecomputeValue(node: unknown): void; consumerMarkedDirty(node: unknown): void; consumerOnSignalRead(node: unknown): void; } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
50. interface ConsumerNode extends ReactiveNode interface ProducerNode extends ReactiveNode export interface ReactiveNode { version: Version; lastCleanEpoch: Version; dirty: boolean; producerNode: ReactiveNode[] | undefined; producerLastReadVersion: Version[] | undefined; producerIndexOfThis: number[] | undefined; nextProducerIndex: number; liveConsumerNode: ReactiveNode[] | undefined; liveConsumerIndexOfThis: number[] | undefined; consumerAllowSignalWrites: boolean; readonly consumerIsAlwaysLive: boolean; producerMustRecompute(node: unknown): boolean; producerRecomputeValue(node: unknown): void; consumerMarkedDirty(node: unknown): void; consumerOnSignalRead(node: unknown): void; } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 dirty: boolean; interface ConsumerNode extends ReactiveNode 1 2 interface ProducerNode extends ReactiveNode 3 4 export interface ReactiveNode { 5 version: Version; 6 lastCleanEpoch: Version; 7 8 producerNode: ReactiveNode[] | undefined; 9 producerLastReadVersion: Version[] | undefined; 10 producerIndexOfThis: number[] | undefined; 11 nextProducerIndex: number; 12 liveConsumerNode: ReactiveNode[] | undefined; 13 liveConsumerIndexOfThis: number[] | undefined; 14 consumerAllowSignalWrites: boolean; 15 readonly consumerIsAlwaysLive: boolean; 16 producerMustRecompute(node: unknown): boolean; 17 producerRecomputeValue(node: unknown): void; 18 consumerMarkedDirty(node: unknown): void; 19 consumerOnSignalRead(node: unknown): void; 20 } 21
51. interface ConsumerNode extends ReactiveNode interface ProducerNode extends ReactiveNode export interface ReactiveNode { version: Version; lastCleanEpoch: Version; dirty: boolean; producerNode: ReactiveNode[] | undefined; producerLastReadVersion: Version[] | undefined; producerIndexOfThis: number[] | undefined; nextProducerIndex: number; liveConsumerNode: ReactiveNode[] | undefined; liveConsumerIndexOfThis: number[] | undefined; consumerAllowSignalWrites: boolean; readonly consumerIsAlwaysLive: boolean; producerMustRecompute(node: unknown): boolean; producerRecomputeValue(node: unknown): void; consumerMarkedDirty(node: unknown): void; consumerOnSignalRead(node: unknown): void; } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 dirty: boolean; interface ConsumerNode extends ReactiveNode 1 2 interface ProducerNode extends ReactiveNode 3 4 export interface ReactiveNode { 5 version: Version; 6 lastCleanEpoch: Version; 7 8 producerNode: ReactiveNode[] | undefined; 9 producerLastReadVersion: Version[] | undefined; 10 producerIndexOfThis: number[] | undefined; 11 nextProducerIndex: number; 12 liveConsumerNode: ReactiveNode[] | undefined; 13 liveConsumerIndexOfThis: number[] | undefined; 14 consumerAllowSignalWrites: boolean; 15 readonly consumerIsAlwaysLive: boolean; 16 producerMustRecompute(node: unknown): boolean; 17 producerRecomputeValue(node: unknown): void; 18 consumerMarkedDirty(node: unknown): void; 19 consumerOnSignalRead(node: unknown): void; 20 } 21 version: Version; dirty: boolean; interface ConsumerNode extends ReactiveNode 1 2 interface ProducerNode extends ReactiveNode 3 4 export interface ReactiveNode { 5 6 lastCleanEpoch: Version; 7 8 producerNode: ReactiveNode[] | undefined; 9 producerLastReadVersion: Version[] | undefined; 10 producerIndexOfThis: number[] | undefined; 11 nextProducerIndex: number; 12 liveConsumerNode: ReactiveNode[] | undefined; 13 liveConsumerIndexOfThis: number[] | undefined; 14 consumerAllowSignalWrites: boolean; 15 readonly consumerIsAlwaysLive: boolean; 16 producerMustRecompute(node: unknown): boolean; 17 producerRecomputeValue(node: unknown): void; 18 consumerMarkedDirty(node: unknown): void; 19 consumerOnSignalRead(node: unknown): void; 20 } 21
52. export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { if (!producerUpdatesAllowed()) { throwInvalidWriteToSignalError(); } if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } } 1 2 3 4 5 6 7 8 9 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 https://github.com/angular/angular/blob/1872fcd8e09fefb52f9b36e8261702cd6fb03f85/packages/core/primitives/signals/src/signal.ts
53. export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { if (!producerUpdatesAllowed()) { throwInvalidWriteToSignalError(); } if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } } 1 2 3 4 5 6 7 8 9 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 function signalValueChanged<T>(node: SignalNode<T>): void { node.version++; producerIncrementEpoch(); producerNotifyConsumers(node); postSignalSetFn?.(); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 signalValueChanged(node); 8 } 9 } 10 11 // ... 12 13 14 15 16 17 18 19 https://github.com/angular/angular/blob/1872fcd8e09fefb52f9b36e8261702cd6fb03f85/packages/core/primitives/signals/src/signal.ts
54. export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { if (!producerUpdatesAllowed()) { throwInvalidWriteToSignalError(); } if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } } 1 2 3 4 5 6 7 8 9 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 function signalValueChanged<T>(node: SignalNode<T>): void { node.version++; producerIncrementEpoch(); producerNotifyConsumers(node); postSignalSetFn?.(); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 signalValueChanged(node); 8 } 9 } 10 11 // ... 12 13 14 15 16 17 18 19 if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 6 7 8 9 } 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 https://github.com/angular/angular/blob/1872fcd8e09fefb52f9b36e8261702cd6fb03f85/packages/core/primitives/signals/src/signal.ts
55. export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { if (!producerUpdatesAllowed()) { throwInvalidWriteToSignalError(); } if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } } 1 2 3 4 5 6 7 8 9 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 function signalValueChanged<T>(node: SignalNode<T>): void { node.version++; producerIncrementEpoch(); producerNotifyConsumers(node); postSignalSetFn?.(); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 signalValueChanged(node); 8 } 9 } 10 11 // ... 12 13 14 15 16 17 18 19 if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 6 7 8 9 } 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 signalValueChanged(node); function signalValueChanged<T>(node: SignalNode<T>): void { node.version++; producerIncrementEpoch(); producerNotifyConsumers(node); postSignalSetFn?.(); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 8 } 9 } 10 11 // ... 12 13 14 15 16 17 18 19 https://github.com/angular/angular/blob/1872fcd8e09fefb52f9b36e8261702cd6fb03f85/packages/core/primitives/signals/src/signal.ts
56. export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { if (!producerUpdatesAllowed()) { throwInvalidWriteToSignalError(); } if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } } 1 2 3 4 5 6 7 8 9 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 function signalValueChanged<T>(node: SignalNode<T>): void { node.version++; producerIncrementEpoch(); producerNotifyConsumers(node); postSignalSetFn?.(); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 signalValueChanged(node); 8 } 9 } 10 11 // ... 12 13 14 15 16 17 18 19 if (!node.equal(node.value, newValue)) { node.value = newValue; signalValueChanged(node); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 6 7 8 9 } 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 node.version++; 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 signalValueChanged(node); function signalValueChanged<T>(node: SignalNode<T>): void { node.version++; producerIncrementEpoch(); producerNotifyConsumers(node); postSignalSetFn?.(); } export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 8 } 9 } 10 11 // ... 12 13 14 15 16 17 18 19 signalValueChanged(node); node.version++; export function signalSetFn<T>(node: SignalNode<T>, newValue: T) { 1 if (!producerUpdatesAllowed()) { 2 throwInvalidWriteToSignalError(); 3 } 4 5 if (!node.equal(node.value, newValue)) { 6 node.value = newValue; 7 8 } 9 } 10 11 // ... 12 13 function signalValueChanged<T>(node: SignalNode<T>): void { 14 15 producerIncrementEpoch(); 16 producerNotifyConsumers(node); 17 postSignalSetFn?.(); 18 } 19 https://github.com/angular/angular/blob/1872fcd8e09fefb52f9b36e8261702cd6fb03f85/packages/core/primitives/signals/src/signal.ts
57. todos = signal<Todo[]>([]); count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); todos.update((items) => [...items, { ... }]); // CHANGE 1 2 3 4 5 6 7 8 9
58. Signal todos() Reactive Context effect() / HTML computed()
59. Signal todos() Reactive Context effect() / HTML computed() dirty
60. Signal todos() Reactive Context effect() / HTML computed() dirty dirty
61. Signal todos() Reactive Context effect() / HTML computed() dirty dirty ask
62. Signal todos() Reactive Context effect() / HTML computed() dirty dirty ask ask
63. Signal todos() Reactive Context effect() / HTML computed()
64. Signal todos() Reactive Context effect() / HTML computed() version++
65. Signal todos() Reactive Context effect() / HTML computed() version++
66. Signal todos() Reactive Context effect() / HTML computed() version++ pull value
67. Signal todos() Reactive Context effect() / HTML computed() version++ pull value version++
68. Signal todos() Reactive Context effect() / HTML computed() version++ pull value version++
69. Signal todos() Reactive Context effect() / HTML computed() version++ pull value version++ pull value
70. todos = signal<Todo[]>([]); count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); todos.update((items) => [...items]); // "NO" CHANGE 1 2 3 4 5 6 7 8 9
71. todos = signal<Todo[]>([]); count = computed(() => todos().length); effect(() => { console.log('Todos count changed to ', count()); }); todos.update((items) => [...items]); // "NO" CHANGE 1 2 3 4 5 6 7 8 9 todos.update((items) => [...items]); // "NO" CHANGE todos = signal<Todo[]>([]); 1 2 count = computed(() => todos().length); 3 4 effect(() => { 5 console.log('Todos count changed to ', count()); 6 }); 7 8 9
72. todos.update((items) => [...items]); // Only ref change todos = signal<Todo[]>([]); 1 2 count = computed(() => todos().length); 3 4 effect(() => { 5 console.log('Todos count changed to ', count()); 6 }); 7 8 9 export function defaultEquals<T>(a: T, b: T) { return Object.is(a, b); } 1 2 3 https://github.com/angular/angular/blob/23eafb4aa20f45233b22a62fe032e47ac21eca20/packages/core/primitives/signals/src/equality.ts#L17
73. Signal todos() Reactive Context effect() / HTML computed()
74. Signal todos() Reactive Context effect() / HTML computed() dirty
75. Signal todos() Reactive Context effect() / HTML computed() dirty dirty
76. Signal todos() Reactive Context effect() / HTML computed() dirty dirty ask
77. Signal todos() Reactive Context effect() / HTML computed() dirty dirty ask ask
78. Signal todos() Reactive Context effect() / HTML computed()
79. Signal todos() Reactive Context effect() / HTML computed() version++
80. Signal todos() Reactive Context effect() / HTML computed() version++
81. Signal todos() Reactive Context effect() / HTML computed() version++ pull value
82. Signal todos() Reactive Context effect() / HTML computed() Same length! version++ pull value
83. Dependency Tracking Dynamic
84. computed(() => isEven() ? getDoneLength() : getUndoneLength() ); 1 2 3 4
85. computed(() => isEven() ? getDoneLength() : getUndoneLength() ); 1 2 3 4 [isEven, getDoneLength] [isEven, getUndoneLength] 1 2 3 [isEven, getDoneLength] 1 2 [isEven, getUndoneLength] 3
86. computed(() => isEven() ? getDoneLength() : getUndoneLength() ); 1 2 3 4 [isEven, getDoneLength] [isEven, getUndoneLength] 1 2 3 [isEven, getDoneLength] 1 2 [isEven, getUndoneLength] 3 [isEven, getUndoneLength] [isEven, getDoneLength] 1 2 3
87. Demo
88. Ways to Use Signals
89. Component
90. export class TodoMainComponent implements OnInit { private url = `${environment.apiUrl}todos`; private http = inject(HttpClient); private todos = signal<Todo[]>([]); count = computed(() => this.todos().length); doneItems = computed(() => this.todos().filter((item) => item.done)?.length); openItems = computed(() => this.todos().filter((item) => !item.done)?.length); sortedTodos = computed(() => this.todos().sort((b, a) => +b.done - +a.done)); // Method logic with http... } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
91. Service
92. Service a a tractio
93. @Injectable({ providedIn: 'root' }) export class TodoService { private url = `${environment.apiUrl}todos`; private http = inject(HttpClient); private todos = signal<Todo[]>([]); count = computed(() => this.todos().length); doneItems = computed(() => this.todos().filter((item) => item.done)?.length); openItems = computed(() => this.todos().filter((item) => !item.done)?.length); sortedTodos = computed(() => this.todos().sort((b, a) => +b.done - +a.done)); getItems() { this.http.get<Todo[]>(this.url).subscribe((todos) => this.todos.set(todos)); } replaceItem() { this.todos.update((items) => [...items]); } addItem(value: string) { this.http.post<Todo>(this.url, { value }).subscribe((addedTodo) => { this.todos.update((items) => [addedTodo, ...items]); }); } updateItem(value: Todo) { // ... } removeItem(id: string) { this.http.delete(`${this.url}/${id}`).subscribe(() => { this.todos.update((items) => [...items.filter((item) => item.id !== id)]); }); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
94. export class TodoMainComponent implements OnInit { private todoService = inject(TodoService); count = this.todoService.count; doneItems = this.todoService.doneItems; openItems = this.todoService.openItems; sortedTodos = this.todoService.sortedTodos; constructor() { effect(() => { console.log('Todos changed (effect):', this.count()); }); } ngOnInit(): void { this.todoService.getItems(); } addTodo(value: string) { this.todoService.addItem(value); } deleteTodo(item: Todo): void { this.todoService.removeitem(item.id); } markAsDone(item: Todo): void { this.todoService.updateItem(item); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
98. Store
99. Store a a tractio
100. @Component({ /* ... */ }) export class TodoMainComponent { private readonly store = inject(Store); items$: Observable<Todo[]>; ngOnInit(): void { this.items$ = this.store.pipe(select(getAllItems)); this.store.dispatch(TodoActions.loadAllTodos()); } } 1 2 3 4 5 6 7 8 9 10 11 12 13
101. @Component({ /* ... */ }) export class TodoMainComponent { private readonly store = inject(Store); items$: Observable<Todo[]>; ngOnInit(): void { this.items$ = this.store.pipe(select(getAllItems)); this.store.dispatch(TodoActions.loadAllTodos()); } } 1 2 3 4 5 6 7 8 9 10 11 12 13
102. @Component({ /* ... */ }) export class TodoMainComponent { private readonly store = inject(Store); items$: Observable<Todo[]>; ngOnInit(): void { this.items$ = this.store.pipe(select(getAllItems)); this.store.dispatch(TodoActions.loadAllTodos()); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 <app-todo-list [items]="items$ | async" /> 1
103. All RXJS
104. @Component({ /* ... */ }) export class TodoMainComponent { private readonly store = inject(Store); items$: Observable<Todo[]>; ngOnInit(): void { this.items$ = this.store.pipe(select(getAllItems)); this.store.dispatch(TodoActions.loadAllTodos()); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 <app-todo-list [items]="items$ | async" /> 1
105. items: Signal<Todo[]>; this.items$ = this.store.selectSignal(getAllItems); 1 @Component({ /* ... */ }) 2 export class TodoMainComponent { 3 private readonly store = inject(Store); 4 5 6 7 ngOnInit(): void { 8 9 10 this.store.dispatch(TodoActions.loadAllTodos()); 11 } 12 } 13
106. items: Signal<Todo[]>; this.items$ = this.store.selectSignal(getAllItems); 1 @Component({ /* ... */ }) 2 export class TodoMainComponent { 3 private readonly store = inject(Store); 4 5 6 7 ngOnInit(): void { 8 9 10 this.store.dispatch(TodoActions.loadAllTodos()); 11 } 12 } 13 <app-todo-list [items]="items()" /> 1
107. items: Signal<Todo[]>; this.items$ = this.store.selectSignal(getAllItems); 1 @Component({ /* ... */ }) 2 export class TodoMainComponent { 3 private readonly store = inject(Store); 4 5 6 7 ngOnInit(): void { 8 9 10 this.store.dispatch(TodoActions.loadAllTodos()); 11 } 12 } 13 @Component({ /* ... */ }) export class TodoMainComponent { private readonly store = inject(Store); items: Signal<Todo[]>; ngOnInit(): void { this.items$ = this.store.selectSignal(getAllItems); this.store.dispatch(TodoActions.loadAllTodos()); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 <app-todo-list [items]="items()" /> 1
108. Partly RXJS
109. Partly RXJS Partly Signals
110. Ngrx Signal Store
111. Lighweight
112. Functional
113. Extensible
114. Optional Rxjs
115. export const TodoStore = signalStore( withState(...), ); 1 2 3 4 5 6 7 8 9 10 11 12 13
116. export interface TodoState { items: Todo[]; loading: boolean; } export const initialState: TodoState = { items: [], loading: false, }; export const TodoStore = signalStore( withState(initialState), ); 1 2 3 4 5 6 7 8 9 10 11 12 13
117. export interface TodoState { items: Todo[]; loading: boolean; } export const initialState: TodoState = { items: [], loading: false, }; export const TodoStore = signalStore( withState(initialState), ); 1 2 3 4 5 6 7 8 9 10 11 12 13 export interface TodoState { items: Todo[]; loading: boolean; } 1 2 3 4 5 export const initialState: TodoState = { 6 items: [], 7 loading: false, 8 }; 9 10 export const TodoStore = signalStore( 11 withState(initialState), 12 ); 13
118. export interface TodoState { items: Todo[]; loading: boolean; } export const initialState: TodoState = { items: [], loading: false, }; export const TodoStore = signalStore( withState(initialState), ); 1 2 3 4 5 6 7 8 9 10 11 12 13 export interface TodoState { items: Todo[]; loading: boolean; } 1 2 3 4 5 export const initialState: TodoState = { 6 items: [], 7 loading: false, 8 }; 9 10 export const TodoStore = signalStore( 11 withState(initialState), 12 ); 13 export const initialState: TodoState = { items: [], loading: false, }; export interface TodoState { 1 items: Todo[]; 2 loading: boolean; 3 } 4 5 6 7 8 9 10 export const TodoStore = signalStore( 11 withState(initialState), 12 ); 13
119. export interface TodoState { items: Todo[]; loading: boolean; } export const initialState: TodoState = { items: [], loading: false, }; export const TodoStore = signalStore( withState(initialState), ); 1 2 3 4 5 6 7 8 9 10 11 12 13 export interface TodoState { items: Todo[]; loading: boolean; } 1 2 3 4 5 export const initialState: TodoState = { 6 items: [], 7 loading: false, 8 }; 9 10 export const TodoStore = signalStore( 11 withState(initialState), 12 ); 13 export const initialState: TodoState = { items: [], loading: false, }; export interface TodoState { 1 items: Todo[]; 2 loading: boolean; 3 } 4 5 6 7 8 9 10 export const TodoStore = signalStore( 11 withState(initialState), 12 ); 13 export const TodoStore = signalStore( withState(initialState), ); export interface TodoState { 1 items: Todo[]; 2 loading: boolean; 3 } 4 5 export const initialState: TodoState = { 6 items: [], 7 loading: false, 8 }; 9 10 11 12 13
120. export const TodoStore = signalStore( withState({ /* ... */ }), withMethods((...) => ({ // ... })) ); 1 2 3 4 5 6
121. export const TodoStore = signalStore( withState({ /* ... */ }), withMethods((...) => ({ // ... })) ); 1 2 3 4 5 6 withMethods((...) => ({ // ... })) export const TodoStore = signalStore( 1 withState({ /* ... */ }), 2 3 4 5 ); 6
122. export const TodoStore = signalStore( withState({ /* ... */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos() { // use Todoservice and then patchState(store, { items }); }, })) ); 1 2 3 4 5 6 7 8 9
123. export const TodoStore = signalStore( withState({ /* ... */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos() { // use Todoservice and then patchState(store, { items }); }, })) ); 1 2 3 4 5 6 7 8 9 withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos() { // use Todoservice and then patchState(store, { items }); }, })) export const TodoStore = signalStore( 1 withState({ /* ... */ ), 2 3 4 5 6 7 8 ); 9
124. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
125. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 5 6 7 8 9 10 11 12 13 14 15 16 17 })) 18 ); 19
126. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 5 6 7 8 9 10 11 12 13 14 15 16 17 })) 18 ); 19 patchState(store, {loading: true}); export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos: rxMethod( 5 switchMap(() => { 6 7 8 return todoService.getItems().pipe( 9 tapResponse({ 10 next: (items) => patchState(store, {items}), 11 error: console.error, 12 finalize: () => patchState(store, {loading: false}), 13 }) 14 ); 15 }) 16 ), 17 })) 18 ); 19
127. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 5 6 7 8 9 10 11 12 13 14 15 16 17 })) 18 ); 19 patchState(store, {loading: true}); export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos: rxMethod( 5 switchMap(() => { 6 7 8 return todoService.getItems().pipe( 9 tapResponse({ 10 next: (items) => patchState(store, {items}), 11 error: console.error, 12 finalize: () => patchState(store, {loading: false}), 13 }) 14 ); 15 }) 16 ), 17 })) 18 ); 19 return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos: rxMethod( 5 switchMap(() => { 6 patchState(store, {loading: true}); 7 8 9 10 11 12 13 14 15 }) 16 ), 17 })) 18 ); 19
128. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 loadAllTodos: rxMethod( switchMap(() => { patchState(store, {loading: true}); return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); }) ), export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 5 6 7 8 9 10 11 12 13 14 15 16 17 })) 18 ); 19 patchState(store, {loading: true}); export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos: rxMethod( 5 switchMap(() => { 6 7 8 return todoService.getItems().pipe( 9 tapResponse({ 10 next: (items) => patchState(store, {items}), 11 error: console.error, 12 finalize: () => patchState(store, {loading: false}), 13 }) 14 ); 15 }) 16 ), 17 })) 18 ); 19 return todoService.getItems().pipe( tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) ); export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos: rxMethod( 5 switchMap(() => { 6 patchState(store, {loading: true}); 7 8 9 10 11 12 13 14 15 }) 16 ), 17 })) 18 ); 19 tapResponse({ next: (items) => patchState(store, {items}), error: console.error, finalize: () => patchState(store, {loading: false}), }) export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos: rxMethod( 5 switchMap(() => { 6 patchState(store, {loading: true}); 7 8 return todoService.getItems().pipe( 9 10 11 12 13 14 ); 15 }) 16 ), 17 })) 18 ); 19
129. Optional Rxjs
130. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos(store, todoService: TodoService) { ... }, async loadAllTodosByPromise() { patchState(store, { loading: true }); const items = await todoService.getItemsAsPromise(); patchState(store, { items, loading: false }); }, })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
131. export const TodoStore = signalStore( { providedIn: 'root' }, withState({ /* state goes here */ ), withMethods((store, todoService = inject(TodoService)) => ({ loadAllTodos(store, todoService: TodoService) { ... }, async loadAllTodosByPromise() { patchState(store, { loading: true }); const items = await todoService.getItemsAsPromise(); patchState(store, { items, loading: false }); }, })) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 async loadAllTodosByPromise() { patchState(store, { loading: true }); const items = await todoService.getItemsAsPromise(); patchState(store, { items, loading: false }); }, export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState({ /* state goes here */ ), 3 withMethods((store, todoService = inject(TodoService)) => ({ 4 loadAllTodos(store, todoService: TodoService) { ... }, 5 6 7 8 9 10 11 12 13 })) 14 ); 15
132. Logic UI
133. Logic UI Stor
134. Logic UI Stor
135. Logic UI Stor BL, Events, RxJs, WebSockets, ...
136. Logic UI Stor BL, Events, RxJs, WebSockets, ... Signals, Methods
137. Logic UI Stor BL, Events, RxJs, WebSockets, ... Signals, Methods Computed, (A)Sync Glue
138. @Component({ // ... providers: [TodoStore], }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); ngOnInit() { this.store.loadAllTodos(); } } 1 2 3 4 5 6 7 8 9 10 11
139. @Component({ // ... providers: [TodoStore], }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); ngOnInit() { this.store.loadAllTodos(); } } 1 2 3 4 5 6 7 8 9 10 11 providers: [TodoStore], @Component({ 1 // ... 2 3 }) 4 export class AppComponent implements OnInit { 5 readonly store = inject(TodoStore); 6 7 ngOnInit() { 8 this.store.loadAllTodos(); 9 } 10 } 11
140. @Component({ // ... providers: [TodoStore], }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); ngOnInit() { this.store.loadAllTodos(); } } 1 2 3 4 5 6 7 8 9 10 11 providers: [TodoStore], @Component({ 1 // ... 2 3 }) 4 export class AppComponent implements OnInit { 5 readonly store = inject(TodoStore); 6 7 ngOnInit() { 8 this.store.loadAllTodos(); 9 } 10 } 11 readonly store = inject(TodoStore); @Component({ 1 // ... 2 providers: [TodoStore], 3 }) 4 export class AppComponent implements OnInit { 5 6 7 ngOnInit() { 8 this.store.loadAllTodos(); 9 } 10 } 11
141. @Component({ // ... providers: [TodoStore], }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); ngOnInit() { this.store.loadAllTodos(); } } 1 2 3 4 5 6 7 8 9 10 11 providers: [TodoStore], @Component({ 1 // ... 2 3 }) 4 export class AppComponent implements OnInit { 5 readonly store = inject(TodoStore); 6 7 ngOnInit() { 8 this.store.loadAllTodos(); 9 } 10 } 11 readonly store = inject(TodoStore); @Component({ 1 // ... 2 providers: [TodoStore], 3 }) 4 export class AppComponent implements OnInit { 5 6 7 ngOnInit() { 8 this.store.loadAllTodos(); 9 } 10 } 11 this.store.loadAllTodos(); @Component({ 1 // ... 2 providers: [TodoStore], 3 }) 4 export class AppComponent implements OnInit { 5 readonly store = inject(TodoStore); 6 7 ngOnInit() { 8 9 } 10 } 11
142. template: `{{ store.items() }} {{ store.loading() }}`, readonly store = inject(TodoStore); @Component({ 1 // ... 2 3 providers: [TodoStore], 4 }) 5 export class AppComponent implements OnInit { 6 7 8 ngOnInit() { 9 this.store.loadAllTodos(); 10 } 11 } 12
143. export const TodoStore = signalStore( { providedIn: 'root' }, withState(initialState), withMethods(/* ... */), withHooks({ // Hooks }) ); 1 2 3 4 5 6 7 8
144. export const TodoStore = signalStore( { providedIn: 'root' }, withState(initialState), withMethods(/* ... */), withHooks({ // Hooks }) ); 1 2 3 4 5 6 7 8 withHooks({ // Hooks }) ); export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState(initialState), 3 withMethods(/* ... */), 4 5 6 7 8
145. export const TodoStore = signalStore( { providedIn: 'root' }, withState(initialState), withMethods(/* ... */), withHooks({ onInit({ loadAllTodos }) { loadAllTodos(); }, onDestroy() { console.log('on destroy'); }, }) ); 1 2 3 4 5 6 7 8 9 10 11 12 13
146. export const TodoStore = signalStore( { providedIn: 'root' }, withState(initialState), withMethods(/* ... */), withHooks({ onInit({ loadAllTodos }) { loadAllTodos(); }, onDestroy() { console.log('on destroy'); }, }) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 withHooks({ onInit({ loadAllTodos }) { loadAllTodos(); }, onDestroy() { console.log('on destroy'); }, }) export const TodoStore = signalStore( 1 { providedIn: 'root' }, 2 withState(initialState), 3 withMethods(/* ... */), 4 5 6 7 8 9 10 11 12 ); 13
147. @Component({ // ... providers: [TodoStore], }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); ngOnInit() { this.store.loadAllTodos(); } } 1 2 3 4 5 6 7 8 9 10 11
148. @Component({ // ... providers: [TodoStore], }) export class AppComponent { readonly store = inject(TodoStore); } 1 2 3 4 5 6 7
149. withComputed((state) => ({ /* ... */ })), export const TodoStore = signalStore( 1 withState(initialState), 2 3 4 5 6 7 withMethods(/* ... */), 8 withHooks(/* ... */) 9 ); 10
150. export const TodoStore = signalStore( withState(initialState), withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), withMethods(/* ... */), withHooks(/* ... */) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
151. export const TodoStore = signalStore( withState(initialState), withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), withMethods(/* ... */), withHooks(/* ... */) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), export const TodoStore = signalStore( 1 withState(initialState), 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21
152. export const TodoStore = signalStore( withState(initialState), withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), withMethods(/* ... */), withHooks(/* ... */) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), export const TodoStore = signalStore( 1 withState(initialState), 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21 doneCount: computed(() => items().filter((x) => x.done).length), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(({ items }) => ({ 4 5 undoneCount: computed(() => items().filter((x) => !x.done).length), 6 percentageDone: computed(() => { 7 const done = items().filter((x) => x.done).length; 8 const total = items().length; 9 10 if (total === 0) { 11 return 0; 12 } 13 14 return (done / total) * 100; 15 }), 16 })), 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21
153. export const TodoStore = signalStore( withState(initialState), withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), withMethods(/* ... */), withHooks(/* ... */) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), export const TodoStore = signalStore( 1 withState(initialState), 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21 doneCount: computed(() => items().filter((x) => x.done).length), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(({ items }) => ({ 4 5 undoneCount: computed(() => items().filter((x) => !x.done).length), 6 percentageDone: computed(() => { 7 const done = items().filter((x) => x.done).length; 8 const total = items().length; 9 10 if (total === 0) { 11 return 0; 12 } 13 14 return (done / total) * 100; 15 }), 16 })), 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21 undoneCount: computed(() => items().filter((x) => !x.done).length), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(({ items }) => ({ 4 doneCount: computed(() => items().filter((x) => x.done).length), 5 6 percentageDone: computed(() => { 7 const done = items().filter((x) => x.done).length; 8 const total = items().length; 9 10 if (total === 0) { 11 return 0; 12 } 13 14 return (done / total) * 100; 15 }), 16 })), 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21
154. export const TodoStore = signalStore( withState(initialState), withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), withMethods(/* ... */), withHooks(/* ... */) ); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 withComputed(({ items }) => ({ doneCount: computed(() => items().filter((x) => x.done).length), undoneCount: computed(() => items().filter((x) => !x.done).length), percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), })), export const TodoStore = signalStore( 1 withState(initialState), 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21 doneCount: computed(() => items().filter((x) => x.done).length), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(({ items }) => ({ 4 5 undoneCount: computed(() => items().filter((x) => !x.done).length), 6 percentageDone: computed(() => { 7 const done = items().filter((x) => x.done).length; 8 const total = items().length; 9 10 if (total === 0) { 11 return 0; 12 } 13 14 return (done / total) * 100; 15 }), 16 })), 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21 undoneCount: computed(() => items().filter((x) => !x.done).length), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(({ items }) => ({ 4 doneCount: computed(() => items().filter((x) => x.done).length), 5 6 percentageDone: computed(() => { 7 const done = items().filter((x) => x.done).length; 8 const total = items().length; 9 10 if (total === 0) { 11 return 0; 12 } 13 14 return (done / total) * 100; 15 }), 16 })), 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21 percentageDone: computed(() => { const done = items().filter((x) => x.done).length; const total = items().length; if (total === 0) { return 0; } return (done / total) * 100; }), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(({ items }) => ({ 4 doneCount: computed(() => items().filter((x) => x.done).length), 5 undoneCount: computed(() => items().filter((x) => !x.done).length), 6 7 8 9 10 11 12 13 14 15 16 })), 17 18 withMethods(/* ... */), 19 withHooks(/* ... */) 20 ); 21
155. @Component({ providers: [TodoStore], templates: ` <div> {{ store.doneCount() }} / {{ store.undoneCount() }} {{ store.percentageDone() }} </div> ` }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); } 1 2 3 4 5 6 7 8 9 10 11
156. @Component({ providers: [TodoStore], templates: ` <div> {{ store.doneCount() }} / {{ store.undoneCount() }} {{ store.percentageDone() }} </div> ` }) export class AppComponent implements OnInit { readonly store = inject(TodoStore); } 1 2 3 4 5 6 7 8 9 10 11 <div> {{ store.doneCount() }} / {{ store.undoneCount() }} {{ store.percentageDone() }} </div> ` @Component({ 1 providers: [TodoStore], 2 templates: ` 3 4 5 6 7 }) 8 export class AppComponent implements OnInit { 9 readonly store = inject(TodoStore); 10 } 11
157. CUSTOM FEATUREs
158. import { computed } from '@angular/core'; import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; export type RequestStatusState = { requestStatus: RequestStatus }; export function withRequestStatus() { return signalStoreFeature( withState<RequestStatusState>({ requestStatus: 'idle' }), withComputed(({ requestStatus }) => ({ isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), })) ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
159. import { computed } from '@angular/core'; import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; export type RequestStatusState = { requestStatus: RequestStatus }; export function withRequestStatus() { return signalStoreFeature( withState<RequestStatusState>({ requestStatus: 'idle' }), withComputed(({ requestStatus }) => ({ isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), })) ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 export function withRequestStatus() { import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22
160. import { computed } from '@angular/core'; import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; export type RequestStatusState = { requestStatus: RequestStatus }; export function withRequestStatus() { return signalStoreFeature( withState<RequestStatusState>({ requestStatus: 'idle' }), withComputed(({ requestStatus }) => ({ isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), })) ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 export function withRequestStatus() { import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 return signalStoreFeature( import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22
161. import { computed } from '@angular/core'; import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; export type RequestStatusState = { requestStatus: RequestStatus }; export function withRequestStatus() { return signalStoreFeature( withState<RequestStatusState>({ requestStatus: 'idle' }), withComputed(({ requestStatus }) => ({ isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), })) ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 export function withRequestStatus() { import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 return signalStoreFeature( import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 withState<RequestStatusState>({ requestStatus: 'idle' }), import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 return signalStoreFeature( 8 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22
162. import { computed } from '@angular/core'; import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; export type RequestStatusState = { requestStatus: RequestStatus }; export function withRequestStatus() { return signalStoreFeature( withState<RequestStatusState>({ requestStatus: 'idle' }), withComputed(({ requestStatus }) => ({ isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), })) ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 export function withRequestStatus() { import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 return signalStoreFeature( import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 withState<RequestStatusState>({ requestStatus: 'idle' }), import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 return signalStoreFeature( 8 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 withComputed(({ requestStatus }) => ({ import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22
163. import { computed } from '@angular/core'; import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; export type RequestStatusState = { requestStatus: RequestStatus }; export function withRequestStatus() { return signalStoreFeature( withState<RequestStatusState>({ requestStatus: 'idle' }), withComputed(({ requestStatus }) => ({ isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), })) ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 export function withRequestStatus() { import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 return signalStoreFeature( import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 withState<RequestStatusState>({ requestStatus: 'idle' }), import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 return signalStoreFeature( 8 9 withComputed(({ requestStatus }) => ({ 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 withComputed(({ requestStatus }) => ({ import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 10 isPending: computed(() => requestStatus() === 'pending'), 11 12 isFulfilled: computed(() => requestStatus() === 'fulfilled'), 13 14 error: computed(() => { 15 const status = requestStatus(); 16 17 return typeof status === 'object' ? status.error : null; 18 }), 19 })) 20 ); 21 } 22 isPending: computed(() => requestStatus() === 'pending'), isFulfilled: computed(() => requestStatus() === 'fulfilled'), error: computed(() => { const status = requestStatus(); return typeof status === 'object' ? status.error : null; }), import { computed } from '@angular/core'; 1 import { signalStoreFeature, withComputed, withState } from '@ngrx/signals'; 2 3 export type RequestStatus = 'idle' | 'pending' | 'fulfilled' | { error: string }; 4 export type RequestStatusState = { requestStatus: RequestStatus }; 5 6 export function withRequestStatus() { 7 return signalStoreFeature( 8 withState<RequestStatusState>({ requestStatus: 'idle' }), 9 withComputed(({ requestStatus }) => ({ 10 11 12 13 14 15 16 17 18 19 })) 20 ); 21 } 22
164. export function setPending(): RequestStatusState { return { requestStatus: 'pending' }; } export function setFulfilled(): RequestStatusState { return { requestStatus: 'fulfilled' }; } export function setError(error: string): RequestStatusState { return { requestStatus: { error } }; } 1 2 3 4 5 6 7 8 9 10 11
165. export const TodoStore = signalStore( withState(initialState), withRequestStatus(), withComputed(/* ... */), withMethods(/* ... */), withHooks(/* ... */) ); readonly store = inject(TodoStore); store.requestStatus(); store.isPending(); store.isFulfilled(); 1 2 3 4 5 6 7 8 9 10 11 12 13
166. export const TodoStore = signalStore( withState(initialState), withRequestStatus(), withComputed(/* ... */), withMethods(/* ... */), withHooks(/* ... */) ); readonly store = inject(TodoStore); store.requestStatus(); store.isPending(); store.isFulfilled(); 1 2 3 4 5 6 7 8 9 10 11 12 13 withRequestStatus(), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(/* ... */), 4 withMethods(/* ... */), 5 withHooks(/* ... */) 6 ); 7 8 readonly store = inject(TodoStore); 9 10 store.requestStatus(); 11 store.isPending(); 12 store.isFulfilled(); 13
167. export const TodoStore = signalStore( withState(initialState), withRequestStatus(), withComputed(/* ... */), withMethods(/* ... */), withHooks(/* ... */) ); readonly store = inject(TodoStore); store.requestStatus(); store.isPending(); store.isFulfilled(); 1 2 3 4 5 6 7 8 9 10 11 12 13 withRequestStatus(), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(/* ... */), 4 withMethods(/* ... */), 5 withHooks(/* ... */) 6 ); 7 8 readonly store = inject(TodoStore); 9 10 store.requestStatus(); 11 store.isPending(); 12 store.isFulfilled(); 13 readonly store = inject(TodoStore); export const TodoStore = signalStore( 1 withState(initialState), 2 withRequestStatus(), 3 withComputed(/* ... */), 4 withMethods(/* ... */), 5 withHooks(/* ... */) 6 ); 7 8 9 10 store.requestStatus(); 11 store.isPending(); 12 store.isFulfilled(); 13
168. export const TodoStore = signalStore( withState(initialState), withRequestStatus(), withComputed(/* ... */), withMethods(/* ... */), withHooks(/* ... */) ); readonly store = inject(TodoStore); store.requestStatus(); store.isPending(); store.isFulfilled(); 1 2 3 4 5 6 7 8 9 10 11 12 13 withRequestStatus(), export const TodoStore = signalStore( 1 withState(initialState), 2 3 withComputed(/* ... */), 4 withMethods(/* ... */), 5 withHooks(/* ... */) 6 ); 7 8 readonly store = inject(TodoStore); 9 10 store.requestStatus(); 11 store.isPending(); 12 store.isFulfilled(); 13 readonly store = inject(TodoStore); export const TodoStore = signalStore( 1 withState(initialState), 2 withRequestStatus(), 3 withComputed(/* ... */), 4 withMethods(/* ... */), 5 withHooks(/* ... */) 6 ); 7 8 9 10 store.requestStatus(); 11 store.isPending(); 12 store.isFulfilled(); 13 store.requestStatus(); store.isPending(); store.isFulfilled(); export const TodoStore = signalStore( 1 withState(initialState), 2 withRequestStatus(), 3 withComputed(/* ... */), 4 withMethods(/* ... */), 5 withHooks(/* ... */) 6 ); 7 8 readonly store = inject(TodoStore); 9 10 11 12 13
169. CUSTOM FEATUREs
170. Extend State
172. Improve This
173. Demo
174. https://github.com/FabianGosebrink/ngrx-signal-store-todo https://github.com/FabianGosebrink/angular-todo-signals
175. Fabian Gosebrink https://offering.solutions Google Developer Expert Microsoft MVP Pluralsight Author
176. Le Fin