Android自定义桌面功能代码实现

import java.io.File;
import java.io.IOException;

import android.app.Activity;
import android.app.WallpaperManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.widget.Toast;

public class WallPaperActivity extends Activity {

    public static final String FILE_NAME = "MM-320x480.png";

    @Override
    protected void onCreate (Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Bitmap wall = getWallPaper();
        setWallPaper(wall);
    }

    //从sdcard中获取图片
    private Bitmap getWallPaper() {
        //拿到sdcard的根目录的路径
        File root = Environment.getExternalStorageDirectory();
        //拿到sdcard中指定的图片
        File wall = new File(root, FILE_NAME);
        //拿到图片的绝对路径
        String path = wall.getAbsolutePath();
        System.out.println("path = " + path);
        //根据图片的绝对路径获取图片
        return BitmapFactory.decodeFile(path);
    }

    //将获取的图片设置为墙纸
    private void setWallPaper(Bitmap wall) {
        //获取一个墙纸管理器的对象
        WallpaperManager wManager = WallpaperManager.getInstance(this);
        try {
            //将对应的图片设置为墙纸
            wManager.setBitmap(wall);
        }
        catch (IOException e) {
            String msg = "设置桌面背景异常：" + e.getLocalizedMessage();
            System.out.println("设置桌面背景异常：" + msg);
            Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
            e.printStackTrace();
        }
    }
}