Android对这种方法进行了封装，我们没有权限去调用这个方法，所以我们只能通过AIDL，然后利用Java的反射机制去调用系统级的方法。

下面上代码：（注释比较详细）

/** * 作用：-----获取包的大小----- * @param context 上下文 * @param pkgName app的包名 * @param appInfo 实体类，用于存放App的某些信息 */ public static void getPkgSize(final Context context, String pkgName, final PhoneAppInfo appInfo) { // getPackageSizeInfo是PackageManager中的一个private方法，所以需要通过反射的机制来调用 Method method; try { method = PackageManager.class.getMethod("getPackageSizeInfo", new Class[]{String.class, IPackageStatsObserver.class}); // 调用 getPackageSizeInfo 方法，需要两个参数：1、需要检测的应用包名；2、回调 method.invoke(context.getPackageManager(), pkgName, new IPackageStatsObserver.Stub() { @Override public void onGetStatsCompleted(PackageStats pStats, boolean succeeded) throws RemoteException { if (succeeded && pStats != null) { synchronized (PhoneAppInfo.class) { appInfo.setCatchSize(pStats.cacheSize);//缓存大小 appInfo.setDataSize(pStats.dataSize); //数据大小 appInfo.setCodeSize(pStats.codeSize); //应用大小 appInfo.setAppSize(pStats.cacheSize + pStats.codeSize + pStats.dataSize);//应用的总大小 Log.d("asdasdxx",appInfo.getAppSize()+""); } } } }); } catch (NoSuchMethodException | InvocationTargetException | IllegalAccessException e) { e.printStackTrace(); } }

下面是两个AIDL文件的代码。。。

步骤（Android Studio）：

1、在main文件夹下，建立一个aidl文件夹的文件夹

2、建立一个包，包名为android.content.pm

3、结构图

*******PackageStats.aidl文件***************

/* //device/java/android/android/view/WindowManager.aidl ** ** Copyright 2007, The Android Open Source Project ** ** Licensed under the Apache License, Version 2.0 (the "License"); ** you may not use this file except in compliance with the License. ** You may obtain a copy of the License at ** ** http://www.apache.org/licenses/LICENSE-2.0 ** ** Unless required by applicable law or agreed to in writing, software ** distributed under the License is distributed on an "AS IS" BASIS, ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ** See the License for the specific language governing permissions and ** limitations under the License. */ package android.content.pm; parcelable PackageStats;

****************IPackageStatusObserver.aidl******************

/* ** ** Copyright 2007, The Android Open Source Project ** ** Licensed under the Apache License, Version 2.0 (the "License"); ** you may not use this file except in compliance with the License. ** You may obtain a copy of the License at ** ** http://www.apache.org/licenses/LICENSE-2.0 ** ** Unless required by applicable law or agreed to in writing, software ** distributed under the License is distributed on an "AS IS" BASIS, ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ** See the License for the specific language governing permissions and ** limitations under the License. */ package android.content.pm; import android.content.pm.PackageStats; /** * API for package data change related callbacks from the Package Manager. * Some usage scenarios include deletion of cache directory, generate * statistics related to code, data, cache usage(TODO) * {@hide} */ oneway interface IPackageStatsObserver { void onGetStatsCompleted(in PackageStats pStats, boolean succeeded); }