Slide 1
Slide 1 text
neverstop
Developing Plugins
for Android Studio
AHMED ALI
ANDROID ENGINEER
SEP 2024
All code examples are
hosted here GITHUB
Slide 2
Slide 2 text
Ahmed
Ali
neverstop
ANDROID ENGINEER
BASED IN CAIRO
@INFINUM
Slide 3
Slide 3 text
• Add a button to the
context menu
• Read the class code
• Send to Gemini
• Write docs
What we are going to build!
Slide 4
Slide 4 text
Let's discuss what we
need to build it!
Slide 5
Slide 5 text
Actions
To register a button in the
context menu
Let's discuss what we
need to build it!
Slide 6
Slide 6 text
Actions
To register a button in the
context menu
Let's discuss what we
need to build it!
PSI
To analyze di
ff
erent coding
elements, and read the body
Slide 7
Slide 7 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
Let's discuss what we
need to build it!
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Slide 8
Slide 8 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
Let's discuss what we
need to build it!
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Running the API calls in the
background and doing updates in
the UI
Threading Model
Slide 9
Slide 9 text
Plugin Types:
Slide 10
Slide 10 text
Plugin Types: Custom Framework Integration
Slide 11
Slide 11 text
Plugin Types:
Custom Framework Integration
Custom Language Support
Slide 12
Slide 12 text
Plugin Types:
Custom Language Support
Tool Integration
Custom Framework Integration
Slide 13
Slide 13 text
Plugin Types:
Tool Integration
Theme Changes
Custom Language Support
Custom Framework Integration
Slide 14
Slide 14 text
Plugin Types:
Theme Changes
User interface add-ons
Tool Integration
Custom Language Support
Custom Framework Integration
Slide 15
Slide 15 text
Creating a Plugin Gradle Project
Slide 16
Slide 16 text
• Install IntelliJ community
• Install plugin DevKit
• Use Latest versions
Creating a Plugin Gradle Project
Slide 17
Slide 17 text
Creating a Plugin Gradle Project
Slide 18
Slide 18 text
Creating a Plugin Gradle Project
• Familair Gradle structure
• build.gradle.kts
• gradle.properties
• settings.gradle.kts
Slide 19
Slide 19 text
Creating a Plugin Gradle Project
• Familair Gradle structure
• build.gradle.kts
• gradle.properties
• settings.gradle.kts
• META-INF/plugin.xml?
Slide 20
Slide 20 text
META-INF/plugin.xml
• Very much like
AndroidManifest.xml
• Declare several components
• Share componentes with other
plugins
Slide 21
Slide 21 text
Plugin config
Slide 22
Slide 22 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Running the API calls in the
background and doing updates in
the UI
Threading Model
Slide 23
Slide 23 text
Actions
• Actions are key to adding interactive
components in the IDE.
• Add items to the platform menus and
toolbars
• Example: File | Open File... menu item and
the Open... toolbar button.
Slide 24
Slide 24 text
How to create an action
• Create a class that extends the
AnAction class.
Slide 25
Slide 25 text
How to create an action
• Create a class that extends the
AnAction class.
• Use the ‘Register Action’ option in
IntelliJ.
Slide 26
Slide 26 text
How to create an action
Slide 27
Slide 27 text
How to create an action
• update() Function:
• Manages visibility and enablement state.
• De
fi
nes logic for when and where the action
should be available.
• Example: Only show the action when right-
clicking on classes or functions.
Slide 28
Slide 28 text
How to create an action
• actionPerformed() Function:
• Executes code when the action is triggered.
• De
fi
nes what happens when the user clicks on
the action.
Slide 29
Slide 29 text
How to create an action
• getActionUpdateThread() Function (introduced
in 2023):
• Speci
fi
es the thread for the action to run on
• EDT or BGT
Slide 30
Slide 30 text
Choosing the Right
Thread
• Use the Main thread for most actions
involving UI updates.
• Use BGT for actions interacting with PSI
elements or the file system.
• If UI updates are needed after a BGT
operation, switch back to the Main thread.
Slide 31
Slide 31 text
Example
Slide 32
Slide 32 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Running the API calls in the
background and doing updates in
the UI
Threading Model
Slide 33
Slide 33 text
PSI
• PSI is a key layer within the IntelliJ platform.
Slide 34
Slide 34 text
PSI
• PSI is a key layer within the IntelliJ platform.
• Handles parsing files and creating syntactic and
semantic code models(AST).
Slide 35
Slide 35 text
PSI
• PSI is a key layer within the IntelliJ platform.
• Handles parsing files and creating syntactic and
semantic code models.
• Simplifies identifying code elements like functions,
classes, etc.
Slide 36
Slide 36 text
PSI
• PSI Files
• PSI Elements
Slide 37
Slide 37 text
PSI Files
• Root structure representing the content of a file.
• Acts as the entry point for understanding the file’s
structure.
• PsiFile is the base class for all PSI files.
• Example: PsiJavaFile for Java files, KtFile for Kotlin.
Slide 38
Slide 38 text
PSI Elements
• Building blocks representing parts of source code
structure.
• Includes everything from whitespace to classes and
functions.
• Provided by the IntelliJ platform for detailed code
exploration.
Slide 39
Slide 39 text
Example
Slide 40
Slide 40 text
Notice something?
Slide 41
Slide 41 text
Notice something?
This is how you add support for custom language,
by implementing your own suite of PsiElements and PsiFiles
Slide 42
Slide 42 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Running the API calls in the
background and doing updates in
the UI
Threading Model
Slide 43
Slide 43 text
Services
• Plugins DI
• A service is a class that can be
loaded on demand
• Each service has only one
instance, making it a singleton
Slide 44
Slide 44 text
Service Level
01
Application
Application Level
Global Singlton
• Works across the
entire IDE’s lifecycle.
• Covers the whole
scope of the
application.
02
Project
Project spec
fi
c
• Speci
fi
c to individual
projects.
• Each project has its
own instance of the
service.
Slide 45
Slide 45 text
Service Type
01
Light
Private
• Private to your plugin
• Simple to setup
02
Non-Light
Exposed
• Exposed to other
plugins
• Needs to be added to
plugin.xml
fi
le
Slide 46
Slide 46 text
Service Light
services
• Create a regular class and annotate it
with @Service.
• Include a Project parameter for project-
level services, automatically injected by
IntelliJ.
Slide 47
Slide 47 text
Service non-light
services
• No need to use @Service
• Needs to be registerd in plugin.xml
Slide 48
Slide 48 text
Service retrieving
• Application-Level Service: Use
getService() method.
• Project-Level Service: Use getService()
within a project context.
• For dependent services, Don’t use
constructor injection.
Slide 49
Slide 49 text
Example
Slide 50
Slide 50 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Running the API calls in the
background and doing updates in
the UI
Threading Model
Slide 51
Slide 51 text
Threading Model
Slide 52
Slide 52 text
Threading Model
• Also known as the UI thread.
• Handles UI events, such as
button clicks and interface
updates.
• Used for writing data
operations as well.
Event Dispatch Thread (EDT)
Slide 53
Slide 53 text
Threading Model
• Also known as the UI thread.
• Handles UI events, such as
button clicks and interface
updates.
• Used for writing data
operations as well.
Event Dispatch Thread (EDT) Background Thread (BGT)
• Handles long-running and
costly operations.
• Ideal for tasks like
fi
le
processing, network calls, and
intensive computations.
Slide 54
Slide 54 text
Coroutines
• Lightweight and easy-to-implement
alternative to traditional threads.
• Recommended by IntelliJ for plugin
development starting in 2024.
• Familiar to Android developers.
Slide 55
Slide 55 text
Coroutines
Dispatchers Scopes Read and Write Locks
Slide 56
Slide 56 text
Dispatchers
• Default, IO,Unconfined, EDT, and
Main dispatchers.
• Main and EDT are the same
• Use EDT dispatcher for UI-
related tasks, as recommended.
Slide 57
Slide 57 text
Scopes
• Multiple scopes available,
including application and project
scopes - Deprecated .
• Service scopes are preferred for
their efficiency and lifecycle
management.
Slide 58
Slide 58 text
Read and write locks
• Crucial for managing read/write operations in
asynchronous environments.
• Writing Allowing Read Action (WARA): Prioritizes
writes; read actions are canceled and retried.
• Writing Blocking Read Action (WBRA): Prioritizes
reads; write actions are blocked until reads
complete.
Slide 59
Slide 59 text
Example
Slide 60
Slide 60 text
Actions
To register a button in the
context menu
The platform way of handling
Dependency Injection
PSI
To analyze di
ff
erent coding
elements, and read the body
Services
Running the API calls in the
background and doing updates in
the UI
Threading Model
Slide 61
Slide 61 text
Usecases
Slide 62
Slide 62 text
UI
Slide 63
Slide 63 text
UI
• Swing
• Kotlin UI dsl
• Compose?
Slide 64
Slide 64 text
UI kotlin UI dsl
• Declartive UI toolkit
• Binding to a state
• Used for panels and dialogs
Slide 65
Slide 65 text
UI Compose
• Not officially supported
• You have to use Jewel
• Check this talk
Slide 66
Slide 66 text
How to learn
more about
plugin dev?
Docs
IntelliJ-community source code
Slack community
Slide 67
Slide 67 text
in
fi
num.com neverstop
Thank you!