What’s new in Android JetPack
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The document discusses various updates in Android Jetpack, focusing on features like CameraX, ViewPager2, and ViewModel with SavedState. It includes details on setting up these components, sample code for implementation, and dependencies required for integration. The document serves as a guide for developers to enhance their apps with these new functionalities.
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Kuala Lumpur
WorkManager (Stable) [sample]](https://image.slidesharecdn.com/googleio192019kualalumpurhassanjetpack1-190618075758/85/What-s-new-in-Android-JetPack-49-320.jpg)
What’s new in Android JetPack
- 1. Extended Kuala Lumpur What’s new in Android JetPack Hassan Abid, GDE Android Twitter, Instagram, Github : @hassanabidpk
- 2. Contents - Alpha - CameraX - LiveData and LifeCycle w/ coroutines - Benchmark - Security - ViewModel with SavedState - ViewPager2 - Beta - ConstraintLayout 2.0 - BioMetric Prompts - Stable - JetPack Compose - WorkManager - Navigation
- 4. CameraX (alpha) - Backward compatible with L+ devices - Consistent behavior across devices - Easy to use APIs - Based on Camera2 Apis but hides Hardware layer
- 5. CameraX - issues tackled - Front/back camera switch crashes - Optimized camera closures - Orientation Incorrect - Flash not firing
- 6. CameraX API (alpha) - Preview - Image Analysis - Image Capture
- 7. Extended Kuala Lumpur Deep dive into CameraX
- 8. Preview API val previewConfig = PreviewConfig.Builder().build()
- 9. Preview API val previewConfig = PreviewConfig.Builder().build() val preview = Preview(previewConfig)
- 10. Preview API val previewConfig = PreviewConfig.Builder().build() val preview = Preview(previewConfig) val textureView: TextureView = findViewById(R.id.textureView)
- 11. Preview API val previewConfig = PreviewConfig.Builder().build() val preview = Preview(previewConfig) val textureView: TextureView = findViewById(R.id.textureView) // The output data-handling is configured in a listener. preview.setOnPreviewOutputUpdateListener { previewOutput -> textureView.surfaceTexture = previewOutput.surfaceTexture }
- 12. Preview API val previewConfig = PreviewConfig.Builder().build() val preview = Preview(previewConfig) val textureView: TextureView = findViewById(R.id.textureView) // The output data-handling is configured in a listener. preview.setOnPreviewOutputUpdateListener { previewOutput -> textureView.surfaceTexture = previewOutput.surfaceTexture } // The use case is bound to an Android Lifecycle with the following code. CameraX.bindToLifecycle(this as LifecycleOwner, preview)
- 14. CameraX Lifecycles - CameraX observes a lifecycle to determine camera states - When to open and close session
- 15. Image Analysis API val imageAnalysisConfig = ImageAnalysisConfig.Builder() .setTargetResolution(Size(1280, 720)) .build()
- 16. Image Analysis API val imageAnalysisConfig = ImageAnalysisConfig.Builder() .setTargetResolution(Size(1280, 720)) .build() val imageAnalysis = ImageAnalysis(imageAnalysisConfig)
- 17. Image Analysis API val imageAnalysisConfig = ImageAnalysisConfig.Builder() .setTargetResolution(Size(1280, 720)) .build() val imageAnalysis = ImageAnalysis(imageAnalysisConfig) imageAnalysis.setAnalyzer({ image: ImageProxy, rotationDegrees: Int -> // insert your code here. })
- 18. Image Analysis API val imageAnalysisConfig = ImageAnalysisConfig.Builder() .setTargetResolution(Size(1280, 720)) .build() val imageAnalysis = ImageAnalysis(imageAnalysisConfig) imageAnalysis.setAnalyzer({ image: ImageProxy, rotationDegrees: Int -> // insert your code here. }) CameraX.bindToLifecycle(this as LifecycleOwner, imageAnalysis, preview)
- 19. Image Capture API (Simplified) val imageCaptureConfig = ImageCaptureConfig.Builder() .setTargetRotation(windowManager.defaultDisplay.rotation) .build() val imageCapture = ImageCapture(imageCaptureConfig) CameraX.bindToLifecycle(this as LifecycleOwner, imageCapture, imageAnalysis, preview)
- 20. Image Capture API (Advance) val imageCaptureConfig = ImageCaptureConfig.Builder().apply { setLensFacing(lensFacing) setCaptureMode(CaptureMode.MIN_LATENCY) // We request aspect ratio but no resolution to match preview config but letting // CameraX optimize for whatever specific resolution best fits requested capture mode setTargetAspectRatio(screenAspectRatio) // Set initial target rotation, we will have to call this again if rotation changes // during the lifecycle of this use case setTargetRotation(viewFinder.display.rotation) }.build()
- 21. Image Capture API (Take Photo) fun onClick() { val file = File(...) imageCapture.takePicture(file, object : ImageCapture.OnImageSavedListener { override fun onError(error: ImageCapture.UseCaseError, message: String, exc: Throwable?) { // insert your code here. } override fun onImageSaved(file: File) { // insert your code here. } })
- 22. Add in build.gradle dependencies { // CameraX core library. def camerax_version = "1.0.0-alpha02" implementation "androidx.camera:camera-core:${camerax_version}" // If you want to use Camera2 extensions. implementation "androidx.camera:camera-camera2:${camerax_version}" }
- 25. Apps using CameraX Camera360 Snow (S10+ plus)
- 26. CameraX resources Code Lab : https://codelabs.developers.google.com/codelabs/camerax-getting-started/#2 Sample App : https://github.com/android/camera/tree/master/CameraXBasic Training : https://developer.android.com/training/camerax
- 28. ViewPager2 - Uses RecyclerView - Adapter - Page Snap Helper - PageChange callbacks - onPageScrolled() - onPageSelected() - onPageScrollStateChanged() - -
- 32. ViewPager2 val adapter = WelcomeAdapter() adapter.welcomeItems = listOf(WelcomeItem.WELCOME_ONE, WelcomeItem.WELCOME_TWO, WelcomeItem.WELCOME_THREE) view_pager.adapter = adapter
- 34. ViewPager2 view_pager.registerOnPageChangeCallback(object : ViewPager2.OnPageChangeCallback() { // override desired callback functions })
- 36. Learning material Sample https://github.com/googlesamples/android-viewpager2 API doc : https://developer.android.com/jetpack/androidx/releases/viewpager2
- 37. Extended Kuala Lumpur ViewModel with SavedState
- 38. ViewModel with SavedState - ViewModel objects can handle UI configuration change - In case of process death, we use onSaveInstanceState() - With ViewModel SavedState - We can save UI state in ViewModel after process death and recover it
- 39. ViewModel with SavedState dependencies { implementation "androidx.lifecycle:lifecycle-extensions:2.1.0-alpha03" kapt "androidx.lifecycle:lifecycle-compiler:2.1.0-alpha03" implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:$1.0.0-alpha01" implementation "androidx.activity:activity-ktx:1.0.0-alpha05" }
- 40. ViewModel with SavedState //In order to set up a ViewModel to receive a SavedStateHandle you need to // create them using a Factory that extends AbstractSavedStateVMFactory. val vm = ViewModelProvider(this, SavedStateVMFactory(this)) .get(SavedStateViewModel::class.java)
- 41. ViewModel with SavedState //After that your ViewModel can have a constructor that receives a SavedStateHandle: class SavedStateViewModel(private val state: SavedStateHandle) : ViewModel() { ... }
- 42. ViewModel with SavedState /* Storing and retrieving values The SavedStateHandle class has the methods you expect for a key-value map: */ get(String key) contains(String key) remove(String key) set(String key, T value) keys() // Code lab : https://codelabs.developers.google.com/codelabs/android-lifecycles/#6
- 44. JetPack Compose - A declarative toolkit for building UI - Part of Android Open source project - Two major components - UI Library - Compiler
- 45. JetPack compose import androidx.compose.* import androidx.ui.core.* @Composable fun Greeting(name: String) { Text ("Hello $name!") }
- 48. Navigation - Stable [sample]
- 49. Extended Kuala Lumpur WorkManager (Stable) [sample]