The technical principles and applications of Android support the library set framework

Android Support Library is a library that provides backwardness for different versions of the Android system.Among them, the SUPPORT Collections Library is part of the SUPPORT LIBRARY, which provides a set of collection framework for processing and operating collection data in Android applications.This article will introduce the technical principles of the SUPPORT Collections Library and its applications in Android applications, and provide some Java code examples. Support Collections Library is a expansion based on the Java collection framework. It provides some additional functions and tools to help developers handle set data more easily.It mainly contains the following functions: 1. Support Collections: Support Collections is the core component of the support collection of collections library. It provides a set of sets that extend the Java set framework.For example, the SparsearrayComPat class is a practical class in the SUPPORT Collections. It provides a sparse array substitution implementation. Compared with ordinary Java arrays, it can process a large number of indexed discontinuous data. 2. Multidex Support: Multidex is a problem that cannot be constructed to solve the problem that the Android application is unable to build due to the number of methods (ie 65,536 methods limit).SUPPORT Collections Library provides support for Multides, allowing developers to distribute the application method to multiple DEX files to bypass this limit. 3. Sparsearray Optimization: In Android development, we often use Sparsearray to replace ordinary hashmap, because Sparsearray has advantages in memory occupation and performance when the key value is small.SUPPORT Collections Library has further improved its performance and efficiency by optimizing the internal implementation of Sparsearray. Here are some examples of Java code for Java code using SUPPORT Collections Library: 1. Create and use SparsearrayCompat: SparseArrayCompat<String> sparseArray = new SparseArrayCompat<>(); sparseArray.put(1, "One"); sparseArray.put(2, "Two"); sparseArray.put(3, "Three"); String value = sparseArray.get(2); System.out.println (value); // Output: TWO int size = sparseArray.size(); System.out.println (size); // Output: 3 2. Use Multidex: First, add Multidex support to the application built.gradle file: android { defaultConfig { // ... multiDexEnabled true } // ... } dependencies { implementation 'com.android.support:multidex:1.0.3' // ... } Then, Multidex is enabled in the Application class: public class MyApplication extends Application { @Override protected void attachBaseContext(Context base) { super.attachBaseContext(base); MultiDex.install(this); } // ... } Through this configuration, you can use the SUPPORT Collections Library function in Android applications, and give full play to its advantages in processing collection data. The above is an introduction to the technical principles of Android Support Library Collections Framework and the introduction of applications in Android applications.By using SUPPORT Collections Library, developers can easily process and operate collection data to improve the performance and efficiency of the application.