Android——获取手机应用图标

需求：

将手机中的所有应用图标，以应用名称命名，后缀为jpg,存放在SD卡中

思路：

1.通过getPackageManager().getInstalledPackages(0)获取已安装的包的信息PackageInfo

2.通过包信息PackageInfo获取包名、版本名、版本号、当然还有应用图标Drawable对象

3.将Drawable对象转换成Bitmap对象再存储即可(。。。目前只能这样了，暂时不知道如何对Drawable进行处理)

代码：

package com.example.utils;

import java.io.File;
import java.io.FileOutputStream;
import java.util.List;

import android.app.Activity;
import android.content.pm.PackageInfo;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.PixelFormat;
import android.graphics.drawable.Drawable;
import android.os.Bundle;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // 获取PackageInfo
        List<PackageInfo> packages = getPackageManager().getInstalledPackages(0);

        // 获取需要的信息并存储(当然这里可以用增强for循环)
        for (int i = 0; i < packages.size(); i++) {
            PackageInfo packageInfo = packages.get(i);
            String appName = packageInfo.applicationInfo.loadLabel(getPackageManager()).toString();
            Drawable appIcon = packageInfo.applicationInfo.loadIcon(getPackageManager());

            // 将drawable转成Bitmap对象
            Bitmap bm = drawableToBitmap(appIcon);

            // 指定存储路径以及存储文件名格式
            File dir = new File("/sdcard/Pictures/");
            File outputImg = new File(dir, appName + ".jpg");
            
            // Bitmap存储过程
            try {
                FileOutputStream out = new FileOutputStream(outputImg);
                bm.compress(Bitmap.CompressFormat.PNG, 90, out);
                out.flush();
                out.close();
                LogUtil.e("test", "已经保存" + i);
            } catch (Exception e) {
                // 不处理异常了
            }

        }
    }

    /**
     * 将Drawable转成Bitmap
     * @param drawable
     * @return
     */
    public Bitmap drawableToBitmap(Drawable drawable) {

        Bitmap bitmap = Bitmap.createBitmap(

        drawable.getIntrinsicWidth(),

        drawable.getIntrinsicHeight(),

        drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888

        : Bitmap.Config.RGB_565);

        Canvas canvas = new Canvas(bitmap);

        // canvas.setBitmap(bitmap);

        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(),
                drawable.getIntrinsicHeight());

        drawable.draw(canvas);

        return bitmap;

    }
}

为了方便，将之封装成一个Util

import java.io.File;
import java.io.FileOutputStream;
import java.util.List;

import android.content.Context;
import android.content.pm.PackageInfo;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.PixelFormat;
import android.graphics.drawable.Drawable;

public class IconUtil {
    private IconUtil() {
        // 不允许实例化这个对象
        throw new UnsupportedOperationException("cannot be instantiated");
    }

    /**
     * 将手机上所有的图标存放到saveDir目录下.<br/>
     * 使用时需要在Manifest中声明两个权限:<br/>
     * android.permission.WRITE_EXTERNAL_STORAGE.<br/>
     * 
     * android.permission.MOUNT_UNMOUNT_FILESYSTEMS.<br/>
     * @param context
     * @param saveDir 存放的手机文件夹目录，如new File("/sdcard/Pictures/");
     * @return i表示图标数量，i=0表示未获取到图标
     */
    public static int saveIcon(Context context, File saveDir) {
        // 获取PackageInfo
        List<PackageInfo> packages = context.getPackageManager().getInstalledPackages(0);
        int i = 0;
        int size = packages.size();
        for (i = 0; i < size; i++) {
            // 从PackageInfo中获取应用名称和应用图标(Drawable)
            PackageInfo packageInfo = packages.get(i);
            String appName = packageInfo.applicationInfo.loadLabel(context.getPackageManager()).toString();
            Drawable appIcon = packageInfo.applicationInfo.loadIcon(context.getPackageManager());

            // 将drawable转成Bitmap对象
            Bitmap bm = drawableToBitmap(appIcon);

            // 指定存储路径以及存储文件名格式
            File outputImg = new File(saveDir, appName + ".png");
            
            // Bitmap存储过程
            try {
                FileOutputStream out = new FileOutputStream(outputImg);
                bm.compress(Bitmap.CompressFormat.PNG, 90, out);
                out.flush();
                out.close();
            } catch (Exception e) {
                // 暂不处理异常
            }
            
        }
        return i;
    }
    
    /**
     * 将Drawable转换成Bitmap
     * @param drawable
     * @return
     */
    public static Bitmap drawableToBitmap(Drawable drawable) {

        Bitmap bitmap = Bitmap.createBitmap(

        drawable.getIntrinsicWidth(),

        drawable.getIntrinsicHeight(),

        drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888

        : Bitmap.Config.RGB_565);

        Canvas canvas = new Canvas(bitmap);

        // canvas.setBitmap(bitmap);

        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(),
                drawable.getIntrinsicHeight());

        drawable.draw(canvas);

        return bitmap;

    }
}

使用举例：MainActivity

注意：Manifest权限声明

注意需要声明权限：

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />

import java.io.File;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.widget.TextView;

public class MainActivity extends Activity {

    private File iconDir;
    private TextView textView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textView = (TextView) findViewById(R.id.text);
        textView.setText("正在获取...");

    }
    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        // 指定存储路径
        String path = Environment.getExternalStorageDirectory().toString() + "/Icons";
        iconDir = new File(path);
        if (!iconDir.exists()) {
            boolean sucess = iconDir.mkdirs();
            if(sucess){
                
                int i = IconUtil.saveIcon(this, iconDir);
                textView.setText("总共获取了  "+i+"  个图标！");
            }else{
                textView.setText("创建文件夹失败！");
            }
            
        }else {
            
            int i = IconUtil.saveIcon(this, iconDir);
            textView.setText("总共获取了  "+i+"  个图标！");
            
        }
    }

    
}

参考：http://www.cnblogs.com/mainroadlee/archive/2011/05/23/android_get_installed_app.html