Android support library file file: Detailed explanation of the framework in the Java class library
Android support library file file: Detailed explanation of the framework in the Java class library
In the development of Android, we often use a series of frameworks and libraries to quickly build functional applications.Android support libraries are one of the very important parts.This article will explain the Android support library archives in detail, and use the Java code example to illustrate the purpose and function of various files.
The Android support library is a series of library file sets developed by Google to enhance the Android application function.These library files contain a class, methods and tools that provide additional functions and characteristics.In the Android support library files, we can find various types of libraries, including compatibility libraries, design libraries, multimedia libraries, etc.
First, let's take a look at the compatibility library.In the Android system, different device versions may have some different API support.To compatible with different versions of Android devices, we can use compatibility libraries.The most commonly used library is the V4 library, which provides some additional methods and classes to expand the old version of the Android framework function.For example, we can use the Fragment class in the V4 library to support the fragment interface that the Android 3.0 is not supported before.
Next is the design library.The design library provides some classes and methods for creating exquisite interfaces.The most commonly used library is the V7 library, which provides some Material Design -style control and layout managers.We can use RecyclerView in the V7 library to achieve highly flexible lists and grid views, and use Toolbar to replace the traditional Action Bar.
In addition, the Android support library also provides some multimedia -related libraries, such as V17 libraries and V18 libraries, which provide support for animation and printing functions respectively.We can use the Animator class in the V17 library to create a smooth animation effect, and the Printhelper class in the V18 library can easily support the printing function.
In addition to the above -mentioned libraries, the Android support library also has many other sub -libraries to provide various functions and characteristics.For example, the V8 and V14 libraries provide some new features and methods that support the Android 2.2 and Android 4.0 version.
Here are some examples of Java code, which demonstrates how to use some common categories and methods in the Android support library archives:
1. Use the Fragment class in the V4 library:
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
Fragment fragment = new MyFragment();
fragmentTransaction.add(R.id.fragment_container, fragment);
fragmentTransaction.commit();
}
}
2. Use the RecyclerView class in the V7 library:
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
private MyAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recycler_view);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
adapter = new MyAdapter();
recyclerView.setAdapter(adapter);
}
}
In summary, the Android support library file file is a very important part that provides a rich class and methods to enhance the function of Android applications.By using these archives, we can develop more android applications with rich characteristics and exquisite interfaces.It is hoped that this article provides some useful information and examples for understanding and using the Android support library file.
