Android之手机壁纸的改变

main.xml布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <Button android:id="@+id/clearWall"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" 
        android:text="恢复默认墙纸" />
    <ImageView android:id="@+id/currWall" 
        android:layout_width="100px"
        android:layout_height="150px"
        android:layout_gravity="center_horizontal" />
    <Button android:id="@+id/getWall" 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" 
        android:text="获取当前墙纸" />
    <Gallery android:id="@+id/gallery"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />
    <Button android:id="@+id/setWall" 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" 
        android:text="设置为当前墙纸" />
</LinearLayout>

清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.ljq.activity"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".WallActivity"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
    <uses-sdk android:minSdkVersion="7" />
    <!-- 设置手机墙纸权限 -->
    <uses-permission android:name="android.permission.SET_WALLPAPER" />
</manifest> 

WallAdapter自定义适配器

package com.ljq.activity;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;

public class WallAdapter extends BaseAdapter {
    private int[] imgIds = null;
    private Context context = null;

    public WallAdapter(int[] imgIds, Context context) {
        super();
        this.imgIds = imgIds;
        this.context = context;
    }

    public int getCount() {
        return imgIds.length;
    }

    public Object getItem(int position) {
        //return imgIds[position];
        return imgIds[position%imgIds.length];//可循环
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView = new ImageView(context);
        imageView.setBackgroundResource(imgIds[position]);// 设置ImageView的背景图片
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new Gallery.LayoutParams(120, 120));
        return imageView;
    }

}

WallActivity类

package com.ljq.activity;

import java.io.IOException;
import java.io.InputStream;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.AdapterView.OnItemSelectedListener;

public class WallActivity extends Activity {
    private int[] imgIds={R.drawable.w1, R.drawable.w2, R.drawable.w3, R.drawable.w4};
    private int selectIndex=-1;//被选中的图片在id数组中的索引
    private ImageView currWall=null;
    private Gallery gallery=null;
    private Button clearWall=null;
    private Button getWall=null;
    private Button setWall=null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        gallery=(Gallery)findViewById(R.id.gallery);
        gallery.setAdapter(new WallAdapter(imgIds, WallActivity.this));
        gallery.setSpacing(5);
        gallery.setOnItemSelectedListener(new OnItemSelectedListener(){
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                selectIndex = position;//记录被选中的图片索引
            }

            public void onNothingSelected(AdapterView<?> parent) {
                
            }
        });
        currWall=(ImageView)findViewById(R.id.currWall);
        clearWall=(Button)findViewById(R.id.clearWall);
        getWall=(Button)findViewById(R.id.getWall);
        setWall=(Button)findViewById(R.id.setWall);
        clearWall.setOnClickListener(listener);
        getWall.setOnClickListener(listener);
        setWall.setOnClickListener(listener);
    }
    
    View.OnClickListener listener=new View.OnClickListener(){

        public void onClick(View v) {
            Button btn=(Button)v;
            switch (btn.getId()) {
            case R.id.clearWall://还原手机壁纸
                try {
                    WallActivity.this.clearWallpaper();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                break;
            case R.id.getWall://设置ImageView显示的内容为当前墙纸
                currWall.setBackgroundDrawable(getWallpaper());
                break;
            case R.id.setWall://设置墙纸
                InputStream in=WallActivity.this.getResources().openRawResource(imgIds[selectIndex]);
                try {
                    setWallpaper(in);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                break;
            }
        }
        
    };
    
}

运行结果