android得到已安裝和未安裝apk的資訊

標籤：android   apk   

         在擷取apk資源時候最重要的一個類就是PackageManager，我們可以通過這個類得到各種想要的東西，首先是得到已經安裝的apk的基本資料，包括label，和表徵圖等資源：

PackageManager pm = getPackageManager();List<PackageInfo> apkInfos = pm.getInstalledPackages(0);ArrayList<String> infos_name =  new ArrayList<String>() ;//用來存放labelArrayList<Drawable> infos_icon = newArrayList<Drawable>();//用來儲存apk啟動表徵圖資源String name = "";   Drawable icon;   PackageInfo apk;   for (int i = 0; i < apkInfos.size(); )   {      apk = apkInfos.get(i);      i++;      name = (String) pm.getApplicationLabel(apk.applicationInfo);      icon = pm.getApplicationIcon(apk.applicationInfo);      infos_icon.add(icon);      infos_name.add(name);   }

        接下來我們利用PackageManager獲得已安裝apk中的activity，和service等

List<PackageInfo>packagesInfo =  pm.getInstalledPackages(0);for (PackageInfo packageInfo : packagesInfo) {Log.d("TAG","packageInfo NAME IS :"+packageInfo.packageName);}PackageManager pm = getPackageManager();try {   //獲得com.example.pertest包中的activity，service和broadcastreceiverPackageInfo packageInfo = pm.getPackageInfo("com.example.pertest",PackageManager.GET_PERMISSIONS| PackageManager.GET_SERVICES| PackageManager.GET_RECEIVERS);ActivityInfo[] activities = packageInfo.activities;if (activities != null) {for (ActivityInfo activityInfo : activities) {Log.d("TAG", "the activity " + activityInfo.toString()+ "==" + packageInfo.versionCode + "==="+ packageInfo.versionName);}} else {Log.d("TAG", "the activity is null");}ServiceInfo[] serviceInfos = packageInfo.services;for (ServiceInfo serviceInfo : serviceInfos) {Log.d("TAG", "service name is :" + serviceInfo.name);}activities = packageInfo.receivers;for (ActivityInfo activity : activities) {Log.d("TAG", "receiver is :" + activity.name);}} catch (NameNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}

上面就是擷取已經安裝的apk的基本資料，接下來看看如何擷取未安裝的apk檔案的基本資料，這對於android動態載入時很有用的，我們來看：

得到未安裝apk的表徵圖：

public static Drawable getAppIcon(Context context, String apkFilepath) {        PackageManager pm = context.getPackageManager();        PackageInfo pkgInfo = getPackageInfo(context, apkFilepath);        if (pkgInfo == null) {            return null;        }        ApplicationInfo appInfo = pkgInfo.applicationInfo;        if (Build.VERSION.SDK_INT >= 8) {            appInfo.sourceDir = apkFilepath;            appInfo.publicSourceDir = apkFilepath;        }        return pm.getApplicationIcon(appInfo);    }

得到未安裝apk的名稱：

public static CharSequence getAppLabel(Context context, String apkFilepath) {        PackageManager pm = context.getPackageManager();        PackageInfo pkgInfo = getPackageInfo(context, apkFilepath);        if (pkgInfo == null) {            return null;        }        ApplicationInfo appInfo = pkgInfo.applicationInfo;        if (Build.VERSION.SDK_INT >= 8) {            appInfo.sourceDir = apkFilepath;            appInfo.publicSourceDir = apkFilepath;        }        return pm.getApplicationLabel(appInfo); }

如果還覺得不夠的話，我們可以得到：PackageInfo對象，通過該對象，我們就可以獲得該未安裝apk的activity，service，broadcastreceiver等，方法同"獲得已安裝apk中的activity，和service"   ,代碼如下：

//得到PackageInfo對象，其中包含了該apk包含的activity和servicepublic static PackageInfo getPackageInfo(Context context, String apkFilepath) {        PackageManager pm = context.getPackageManager();        PackageInfo pkgInfo = null;        try {            pkgInfo = pm.getPackageArchiveInfo(apkFilepath, PackageManager.GET_ACTIVITIES | PackageManager.GET_SERVICES);        } catch (Exception e) {            // should be something wrong with parse            e.printStackTrace();        }        return pkgInfo;    }

        在android動態載入的時候，是通過DexClassLoader來實現的，通過這種方式來擷取未安裝程式的DexClassLoader對象：

String mNativeLibDir = mContext.getDir("pluginlib", Context.MODE_PRIVATE).getAbsolutePath(); private DexClassLoader createDexClassLoader(String dexPath) {        File dexOutputDir = mContext.getDir("dex", Context.MODE_PRIVATE);        dexOutputPath = dexOutputDir.getAbsolutePath();        DexClassLoader loader = new DexClassLoader(dexPath, dexOutputPath, mNativeLibDir, mContext.getClassLoader());        return loader; }

   第一個參數dexPath就是我們apk的存放路徑。

   第二個參數dexOutPath就是該apk檔案對應的dex檔案的存放路徑，不可以為null。

   第三個參數是目標類中使用的C/C++庫的列表,每個目錄用File.pathSeparator間隔開; 可以為 null。

  第四個參數是該類裝載器的父裝載器，一般用當前執行類的裝載器。

在獲得了該DexClassLoader對象以後，我們就可以實現動態載入該apk中的方法了，詳細的方法，請看我的另一篇文章：android動態載入

對於載入未安裝的apk中的資源，由於使用的是不同的context，所以，這裡先這樣做：

 private AssetManager createAssetManager(String dexPath) {        try {            AssetManager assetManager = AssetManager.class.newInstance();            Method addAssetPath = assetManager.getClass().getMethod("addAssetPath", String.class);            addAssetPath.invoke(assetManager, dexPath);            return assetManager;        } catch (Exception e) {            e.printStackTrace();            return null;        }    }private Resources createResources(AssetManager assetManager) {        Resources superRes = mContext.getResources();        Resources resources = new Resources(assetManager, superRes.getDisplayMetrics(), superRes.getConfiguration());        return resources;}

        此時的assetManager和resources就可以和平時一樣來用了。

android得到已安裝和未安裝apk的資訊