android 下获取apk的icon

代码如下：

package com.gem.hsx;

import java.io.File;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;

import android.app.Activity;
import android.content.pm.ApplicationInfo;
import android.content.res.Resources;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.widget.ImageView;

public class TesticonActivity extends Activity {

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		ImageView icon=(ImageView) findViewById(R.id.img_icon);
		icon.setBackgroundDrawable(getApkIcon("/sdcard/12.apk"));



	}
	public  Drawable  getApkIcon(String Path){
		//未安装的程序通过apk文件获取icon
		String apkPath = Path; //   apk  文件所在的路径
		String PATH_PackageParser = "android.content.pm.PackageParser";
		String PATH_AssetManager = "android.content.res.AssetManager";
		try {
			Class pkgParserCls = Class.forName(PATH_PackageParser);
			Class[] typeArgs = { String.class };
			Constructor pkgParserCt = pkgParserCls.getConstructor(typeArgs);
			Object[] valueArgs = { apkPath };
			Object pkgParser = pkgParserCt.newInstance(valueArgs);
			DisplayMetrics metrics = new DisplayMetrics();
			metrics.setToDefaults();
			typeArgs = new Class[] { File.class, String.class,DisplayMetrics.class, int.class };
			Method pkgParser_parsePackageMtd = pkgParserCls.getDeclaredMethod("parsePackage", typeArgs);
			valueArgs = new Object[] { new File(apkPath), apkPath, metrics, 0 };
			Object pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser,valueArgs);
			Field appInfoFld = pkgParserPkg.getClass().getDeclaredField("applicationInfo");
			ApplicationInfo info = (ApplicationInfo) appInfoFld.get(pkgParserPkg);
			Class assetMagCls = Class.forName(PATH_AssetManager);
			Object assetMag = assetMagCls.newInstance();
			typeArgs = new Class[1];
			typeArgs[0] = String.class;
			Method assetMag_addAssetPathMtd = assetMagCls.getDeclaredMethod("addAssetPath", typeArgs);
			valueArgs = new Object[1];
			valueArgs[0] = apkPath;
			assetMag_addAssetPathMtd.invoke(assetMag, valueArgs);
			Resources res = TesticonActivity.this.getResources();
			typeArgs = new Class[3];
			typeArgs[0] = assetMag.getClass();
			typeArgs[1] = res.getDisplayMetrics().getClass();
			typeArgs[2] = res.getConfiguration().getClass();
			Constructor resCt = Resources.class
			.getConstructor(typeArgs);
			valueArgs = new Object[3];
			valueArgs[0] = assetMag;
			valueArgs[1] = res.getDisplayMetrics();
			valueArgs[2] = res.getConfiguration();
			res = (Resources) resCt.newInstance(valueArgs);
			if (info != null) {
				if (info.icon != 0) 
				{
					Drawable  icon=res.getDrawable(info.icon);
					return  icon;
				}
			} 
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}



}