获取SD卡上 未安装 APK文件 的图标等

各版本通用

/**
	 * 获取未安装的apk信息
	 * 
	 * @param ctx
	 * @param apkPath
	 * @return
	 */
	public static AppInfoData getApkFileInfo(Context ctx, String apkPath) {
		System.out.println(apkPath);
		File apkFile = new File(apkPath);
		if (!apkFile.exists() || !apkPath.toLowerCase().endsWith(".apk")) {
			System.out.println("文件路径不正确");
			return null;
		}
		AppInfoData appInfoData;
		String PATH_PackageParser = "android.content.pm.PackageParser";
		String PATH_AssetManager = "android.content.res.AssetManager";
		try {
			//反射得到pkgParserCls对象并实例化,有参数
			Class<?> pkgParserCls = Class.forName(PATH_PackageParser);
			Class<?>[] typeArgs = {String.class};
			Constructor<?> pkgParserCt = pkgParserCls.getConstructor(typeArgs);
			Object[] valueArgs = {apkPath};
			Object pkgParser = pkgParserCt.newInstance(valueArgs);
			
			//从pkgParserCls类得到parsePackage方法
			DisplayMetrics metrics = new DisplayMetrics();
			metrics.setToDefaults();//这个是与显示有关的, 这边使用默认
			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};
			
			//执行pkgParser_parsePackageMtd方法并返回
			Object pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser,
					valueArgs);
			
			//从返回的对象得到名为"applicationInfo"的字段对象	
			if (pkgParserPkg==null) {
				return null;
			}
			Field appInfoFld = pkgParserPkg.getClass().getDeclaredField(
					"applicationInfo");
			
			//从对象"pkgParserPkg"得到字段"appInfoFld"的值
			if (appInfoFld.get(pkgParserPkg)==null) {
				return null;
			}
			ApplicationInfo info = (ApplicationInfo) appInfoFld
					.get(pkgParserPkg);			
			
			//反射得到assetMagCls对象并实例化,无参
			Class<?> assetMagCls = Class.forName(PATH_AssetManager);			
			Object assetMag = assetMagCls.newInstance();
			//从assetMagCls类得到addAssetPath方法
			typeArgs = new Class[1];
			typeArgs[0] = String.class;
			Method assetMag_addAssetPathMtd = assetMagCls.getDeclaredMethod(
					"addAssetPath", typeArgs);
			valueArgs = new Object[1];
			valueArgs[0] = apkPath;
			//执行assetMag_addAssetPathMtd方法
			assetMag_addAssetPathMtd.invoke(assetMag, valueArgs);
			
			
			//得到Resources对象并实例化,有参数
			Resources res = ctx.getResources();
			typeArgs = new Class[3];
			typeArgs[0] = assetMag.getClass();
			typeArgs[1] = res.getDisplayMetrics().getClass();
			typeArgs[2] = res.getConfiguration().getClass();
			Constructor<Resources> 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);
			
			
			// 读取apk文件的信息
			appInfoData = new AppInfoData();
			if (info!=null) {
				if (info.icon != 0) {// 图片存在，则读取相关信息
					Drawable icon = res.getDrawable(info.icon);// 图标
					appInfoData.setAppicon(icon);
					}
				if (info.labelRes != 0) {
					String neme = (String) res.getText(info.labelRes);// 名字
					appInfoData.setAppname(neme);
				}else {
					String apkName=apkFile.getName();
					appInfoData.setAppname(apkName.substring(0,apkName.lastIndexOf(".")));
				}
				String pkgName = info.packageName;// 包名			
				appInfoData.setApppackage(pkgName);
			}else {
				return null;
			}			
			PackageManager pm = ctx.getPackageManager();
			PackageInfo packageInfo = pm.getPackageArchiveInfo(apkPath, PackageManager.GET_ACTIVITIES);
			if (packageInfo != null) {
				appInfoData.setAppversion(packageInfo.versionName);//版本号
				appInfoData.setAppversionCode(packageInfo.versionCode+"");//版本码
			}
			return appInfoData;
		} catch (Exception e) {	
			e.printStackTrace();
		}
		return null;
	}