Common functions and characteristics of Android Support Library V4

Common functions and characteristics of Android Support Library V4 Android Support Library V4 is a compatible expansion library developed by Google for the Android platform to provide new features and better compatibility, enabling developers to use the latest APIs and functions in the lower version of Android system.This article will introduce some common functions and characteristics of Android Support Library V4, and provide some Java code examples to help readers better understand and use the library. 1. Compatibility support Android Support Library V4 offers many tools and classes compatible with different Android versions.These include FragmentCompat and ActivityCompat, which allows us to use the latest Fragment and Activity features on the lower version of Android systems. Example code: // Use FragmentCompat to add a frame Fragment fragment = new MyFragment(); FragmentTransaction transaction = getSupportFragmentManager().beginTransaction(); FragmentCompat.add(transaction, fragment, "TAG"); transaction.commit(); 2. UI component support Android Support Library V4 provides developers with some new UI components that can be used in the low -version Android system.For example, ViewPager and RecyclerView.ViewPage provides a simple way to achieve the effect of sliding page, and RecyclerView is a more flexible and efficient list control. Example code: // Create a viewPager and set the adapter ViewPager viewPager = findViewById(R.id.viewPager); MyPagerAdapter adapter = new MyPagerAdapter(getSupportFragmentManager()); viewPager.setAdapter(adapter); 3. Tool class Android Support Library V4 also provides some practical tool categories to facilitate developers to handle common tasks.For example, the NotificationCompat class enables us to create compatible notices on different versions of the Android system. Example code: // Use NotificationCompat to create a compatible notice NotificationCompat.Builder builder = new NotificationCompat.Builder(context) .setSmallIcon(R.drawable.notification_icon) .setContentTitle("My notification") .setContentText("Hello World!"); NotificationManagerCompat notificationManager = NotificationManagerCompat.from(context); notificationManager.notify(notificationId, builder.build()); 4. Animation support Android Support Library V4 By providing some animation support classes, developers can achieve the animation effect on the low -version Android system.For example, the ViewCompat class provides some static methods for processing view animation. Example code: // Use ViewCompat to achieve a gradient animation ViewCompat.animate(view) .alpha(0f) .setDuration(500) .withEndAction(new Runnable() { @Override public void run() { view.setVisibility(View.GONE); } }) .start(); Summarize: Android Support Library V4 is a powerful compatibility expansion library that provides many commonly used functions and characteristics.This article introduces some of these functions and provides some Java code examples.I hope that by reading this article, readers have a more comprehensive understanding of Android Support Library V4 and can be flexibly used in actual development.