Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Compose Previews as a Power User
Search
Subhrajyoti Sen
October 06, 2024
Programming
230
1
Share
Embed
Copy iframe code
Copy JS code
Copy link
Start on current slide
Compose Previews as a Power User
Subhrajyoti Sen
October 06, 2024
More Decks by Subhrajyoti Sen
See All by Subhrajyoti Sen
Understanding Incremental Processing in the JVM World
subhrajyotisen
0
51
Updated Lessons from a KMP Developer's Toolkit
subhrajyotisen
0
65
Building Mobile Apps and Scaling them
subhrajyotisen
0
73
Understanding WindowInsets
subhrajyotisen
0
260
Exploring a KMM Developer’s Toolkit
subhrajyotisen
1
270
Shipping Apps Confidently with Firebase
subhrajyotisen
0
140
Understanding WindowInsets - Android Worldwide
subhrajyotisen
0
400
Understanding WindowInsets
subhrajyotisen
1
240
Demystifying Styles and Themes
subhrajyotisen
0
290
Other Decks in Programming
See All in Programming
「寝てても仕事が進む」Claude Codeで組む第二の脳
tomoyafujita2016
0
220
複数の Claude Code が"放置"されてしまう問題をCLI ダッシュボードを自作して解決した話
sumihiro3
0
570
Welcome to the "Parametricity" 🏙️ − Generic だけど Specific な世界 −
guvalif
PRO
1
190
生成AI導入の「期待外れ」を乗り越える ー 開発フロー改革が目指す、真の組織変革
starfish719
0
2.8k
アルゴリズムは何を圧縮しているのか ─ Haskell から育った「圧縮代数」というメンタルモデル
naoya
16
3.7k
属人化した知識を、 AIが辿れる地図にする
pkshadeck
PRO
1
120
【やさしく解説 設計編 #0】DDDのコード、読めるのに分からない人へ
panda728
PRO
2
290
Embedded SREと共に達成した会員管理システムのAWS移行 - SRE NEXT 2026 ランチスポンサーセッション
niftycorp
PRO
1
3.2k
PostgreSQL 18で考えるUUID主キー
kazuhiro1982
0
440
TSX の <Hoge<Fuga>> という構文に驚いた話 / tsx-type-argument-syntax
kanaru0928
0
140
jsmini JavaScript Engine を作ってみた話
yosuke_furukawa
PRO
0
280
PHP に部分適用が来るぞ!……ところで何それ?おいしいの? #phpcon / phpcon-2026
shogogg
0
430
Featured
See All Featured
Testing 201, or: Great Expectations
jmmastey
46
8.2k
Sharpening the Axe: The Primacy of Toolmaking
bcantrill
46
2.9k
How Fast Is Fast Enough? [PerfNow 2025]
tammyeverts
3
670
[Rails World 2023 - Day 1 Closing Keynote] - The Magic of Rails
eileencodes
38
2.9k
How to Get Subject Matter Experts Bought In and Actively Contributing to SEO & PR Initiatives.
livdayseo
0
160
Understanding Cognitive Biases in Performance Measurement
bluesmoon
32
3k
It's Worth the Effort
3n
188
29k
Easily Structure & Communicate Ideas using Wireframe
afnizarnur
194
17k
More Than Pixels: Becoming A User Experience Designer
marktimemedia
3
470
Color Theory Basics | Prateek | Gurzu
gurzu
0
400
Mozcon NYC 2025: Stop Losing SEO Traffic
samtorres
1
450
16th Malabo Montpellier Forum Presentation
akademiya2063
PRO
0
310
Transcript
Compose Previews as a Power User Chennai Subhrajyoti Sen Motive
Simple Previews
@Composable fun BorrowedItemRowPreview() { BorrowedItemRow( item = BorrowItem( id =
0, itemName = "XBox Series X", borrowerName = "Steve", borrowDate = "2-11-2023" ) ) }
@Preview @Composable fun BorrowedItemRowPreview() { BorrowedItemRow( item = BorrowItem( id
= 0, itemName = "XBox Series X", borrowerName = "Steve", borrowDate = "2-11-2023" ) ) }
@Preview @Composable fun BorrowedItemRowPreview() { BorrowedItemRow( item = BorrowItem( id
= 0, itemName = "XBoz Series X", borrowerName = "Steve", borrowDate = "2-11-2023" ) ) }
None
Available Arguments • name • group • uiMode • locale
• showSystemUi • showBackground • device • apiLevel
Dark Mode
@Preview(uiMode = UI_MODE_NIGHT_YES) @Composable fun BorrowedItemRowDevicePreview() { BorrowTheme { BorrowedItemRow(
item = //.. ) } }
None
Multi Preview Annotation
@Preview(uiMode = UI_MODE_NIGHT_NO) @Preview(uiMode = UI_MODE_NIGHT_YES) @Composable fun BorrowedItemRowDevicePreview() {
BorrowTheme { BorrowedItemRow( item = //.. ) } }
@Preview(uiMode = UI_MODE_NIGHT_NO) @Preview(uiMode = UI_MODE_NIGHT_YES) annotation class LightDarkThemePreview
@LightDarkThemePreview @Composable fun BorrowedItemRowDevicePreview() { BorrowTheme { BorrowedItemRow( item =
//.. ) } }
@LightDarkThemePreview @Composable fun BorrowedItemRowDevicePreview() { BorrowTheme { BorrowedItemRow( item =
//.. ) } }
None
@Preview( showSystemUi = true, device = Devices.NEXUS_5X ) @Preview( showSystemUi
= true, device = Devices.NEXUS_10 ) annotation class MultiDevicePreview
@Preview( showSystemUi = true, device = Devices.NEXUS_5X ) @Preview( showSystemUi
= true, device = Devices.NEXUS_10 ) annotation class MultiDevicePreview
@Preview(locale = "en") @Preview(locale = "fr-rCA") @Preview(locale = "es-rUS") annotation
class MultiLocalePreview Valid locale format: https://developer.android.com/guide/topics/resources/provid ing-resources#LocaleQualifier
@LightDarkThemePreview @MultiLocalePreview annotation class MultiLocaleLightDarkPreview
Dataset Driven Preview
None
@Preview @Composable fun BorrowedItemRowPreview() { BorrowedItemRow( item = BorrowItem( id
= 0, itemName = "XBox Series X", borrowerName = "Steve", borrowDate = "2-11-2023" ) ) } @Preview @Composable fun BorrowedItemRowPreview() { BorrowedItemRow( item = BorrowItem( id = 0, itemName = "PlayStation", borrowerName = "Steve", borrowDate = "2-11-2023" ) ) }
class BorrowItemsProvider : PreviewParameterProvider<BorrowItem> { override val values = sequenceOf(
BorrowItem( id = 0, itemName = "PlayStation", borrowerName = "Steve", borrowDate = "2-11-2022" ), BorrowItem( id = 0, itemName = "XBox", borrowerName = "Steve", borrowDate = "2-11-2022" ) ) }
class BorrowItemsProvider : PreviewParameterProvider<BorrowItem> { override val values = sequenceOf(
BorrowItem( id = 0, itemName = "PlayStation", borrowerName = "Steve", borrowDate = "2-11-2022" ), BorrowItem( id = 0, itemName = "XBox", borrowerName = "Steve", borrowDate = "2-11-2022" ) ) }
@Preview @Composable fun BorrowedItemRowPreview( @PreviewParameter(BorrowItemsProvider::class) item: BorrowItem ) { BorrowedItemRow(
item ) }
@Preview @Composable fun BorrowedItemRowPreview( @PreviewParameter(BorrowItemsProvider::class) item: BorrowItem ) { BorrowedItemRow(
item ) }
Declutter using Groups
@MultiLocaleLightDarkPreview @Composable fun BorrowedItemRowDevicePreview() { BorrowTheme { BorrowedItemRow( item =
//.. ) } }
None
@Preview(locale = "en", group = "English") @Preview(locale = "fr-rCA", group
= "Canadian French") @Preview(locale = "es-rUS", group = "US Spanish") annotation class MultiLocalePreview
None
Local Inspection
None
@Composable fun BorrowedItemRow(item: BorrowItem) { var expanded by remember {
mutableStateOf(false) } // this will only affect previews if (LocalInspectionMode.current) { expanded = true } //.. }
@Composable fun BorrowedItemRow(item: BorrowItem) { var expanded by remember {
mutableStateOf(false) } // this will only affect previews if (LocalInspectionMode.current) { expanded = true } //.. }
Showkase
None
@ShowkaseComposable(group = "Individual rows") @Preview @Composable fun BorrowedItemRowExpandedPreview() { BorrowTheme
{ BorrowedItemRow( //.. ) } }
@ShowkaseComposable(group = "Individual rows") @Preview @Composable fun BorrowedItemRowExpandedPreview() { BorrowTheme
{ BorrowedItemRow( //.. ) } }
@ShowkaseComposable(group = "Individual rows") @Composable @Preview fun BorrowedItemRowCollapsedPreview() { CompositionLocalProvider(LocalInspectionMode
provides false) { BorrowTheme { BorrowedItemRow( //.. ) } } }
None
None
None
Animation Previews
None
None
updateTransition Supported Animations AnimatedVisibility animate*AsState rememberInfiniteTransition CrossFade AnimatedContent
Screenshot Testing
Available Options
Paparazzi Available Options
Paparazzi Roborazzi Available Options
Paparazzi Roborazzi Compose Preview Available Options
Paparazzi
Works on JVM Paparazzi
Works on JVM Based on Layoutlib Paparazzi
Works on JVM Based on Layoutlib Needs JUnit tests Paparazzi
Works on JVM Based on Layoutlib Needs JUnit tests Paparazzi
Supports Views
Works on JVM Based on Layoutlib Needs JUnit tests Paparazzi
Supports Views Emulates Production
class PaparazziTests { @get:Rule val paparazzi = Paparazzi( deviceConfig =
PIXEL_5.copy(nightMode = NightMode.NIGHT), renderingMode = RenderingMode.SHRINK ) }
class PaparazziTests { @get:Rule val paparazzi = Paparazzi( deviceConfig =
PIXEL_5.copy(nightMode = NightMode.NIGHT), renderingMode = RenderingMode.SHRINK ) }
class PaparazziTests { //.. @Test fun launchComposable() { paparazzi.snapshot {
BorrowTheme { BorrowedItemRow( item = //.. ) } } } }
class PaparazziTests { //.. @Test fun launchComposable() { paparazzi.snapshot {
CompositionLocalProvider(LocalInspectionMode provides true) { BorrowTheme { BorrowedItemRow( item = //.. ) } } } } }
class PaparazziTests { //.. @Test fun launchComposable() { paparazzi.snapshot {
CompositionLocalProvider(LocalInspectionMode provides true) { BorrowTheme { BorrowedItemRow( item = //.. ) } } } } }
Baseline
After changes
Failure Comparison
Compose Preview Screenshot
Works on JVM Compose Preview Screenshot
Works on JVM Based on Layoutlib Compose Preview Screenshot
Works on JVM Based on Layoutlib Fully Automated Compose Preview
Screenshot
Works on JVM Based on Layoutlib Fully Automated Compose Preview
Screenshot Needs a special directory
Works on JVM Based on Layoutlib Fully Automated Compose Preview
Screenshot Needs a special directory Emulates Debug
Compose Preview Screenshot - Source
Compose Preview Screenshot - Source @LightDarkThemePreview @Composable fun BorrowedItemRowPreview( @PreviewParameter(BorrowItemsProvider::class)
item: BorrowItem ) { BorrowedItemRow( item ) }
Compose Preview Screenshot - Destination
Screen Comparison
Screen Comparison
Can’t decide? sergio-sastre/ComposablePreviewScanner
Further Exploration https://github.com/takahirom/roborazzi Composable Preview Driven Development: TDD-fying your UI
with ease!
Questions?
Thank You! Chennai