Android获取app应用程序大小的方法

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);
}