IPackageStatsObserver 无法解析为类型（Android）

Question

我想计算使用设备的所有缓存内存的总和。为此，我收到编译时间错误：

IPackageStatsObserver cannot be resolved to a type

我在代码中已经两次提到这个错误：

public long totalCacheSize(){
    totalSize=0;

    PackageManager packageManager = getApplicationContext().getPackageManager();

     /* List<PackageInfo> packs = packageManager
      .getInstalledPackages(PackageManager.GET_ACTIVITIES);*/
     // PackageManager.GET_META_DATA

    List<PackageInfo> packs = packageManager
            .getInstalledPackages(PackageManager.GET_META_DATA);

    for (int i = 0; i < packs.size(); i++) {

        PackageInfo p = packs.get(i);

        Method getPackageSizeInfo;
        try {
            getPackageSizeInfo = packageManager.getClass()
                    .getMethod("getPackageSizeInfo",
                        String.class, Class.forName("android.content.pm.IPackageStatsObserver"));

            getPackageSizeInfo.invoke(packageManager, p.packageName,
                    new IPackageStatsObserver.Stub() { //error

                        public void onGetStatsCompleted(
                                PackageStats pStats, boolean succeeded)
                                throws RemoteException {

                            totalSize = totalSize + pStats.cacheSize;
                            Log.d("size", totalSize+"");
                            Toast.makeText(getApplicationContext(), "size"+totalSize, Toast.LENGTH_SHORT).show();
                        }
                    }
            );

        } catch (Exception e) {
            try {
                getPackageSizeInfo = packageManager.getClass()
                        .getMethod("getPackageSizeInfo",
                            String.class, Class.forName("android.content.pm.IPackageStatsObserver"));

                getPackageSizeInfo.invoke(packageManager, p.packageName,
                        new IPackageStatsObserver.Stub() { //error

                            public void onGetStatsCompleted(
                                    PackageStats pStats, boolean succeeded)
                                    throws RemoteException {

                                totalSize = totalSize + pStats.cacheSize;
                                Log.d("size", totalSize+"");
                                Toast.makeText(getApplicationContext(), "size"+totalSize, Toast.LENGTH_SHORT).show();
                            }
                        }
                );
            } catch (Exception ee) {
                Log.d("eeeeeeeeeee", "error");
                ee.printStackTrace();
            } 
        } 
    }

    Log.d("return size", totalSize+"");
    Toast.makeText(getApplicationContext(), "return size"+totalSize, Toast.LENGTH_SHORT).show();
    return totalSize;
}

IPackageStatsObserver 在 Android SDK 中不可用。可能使用Class.forName() 加载存根类，找到默认构造函数并调用它以获取Stub 的新实例。但是我应该编码它，我对此一无所知！？

求救！！

Answer 1

要解决您的问题，请按以下步骤操作：

Android Studio

• 右键单击您的项目新建>文件夹> AIDL文件夹
• 按完成
• 右击aidl文件夹新建>包
• 插入android.content.pm 并按确定
• 下载IPackageStatsObserver.aidl
• 复制android.content.pm包内的aidl文件
• 构建 > 重建项目

Eclipse

• 右击src文件夹新建>包
• 插入android.content.pm
• 按完成
• 下载IPackageStatsObserver.aidl
• 复制android.content.pm包内的aidl文件
• 选择 totalCacheSize 所在的类，然后 Source > Organize Imports

Answer 2

您需要在项目中添加IPackageStatsObserver.aidl 和PackageStats.aidl。

Answer 3

更新

在 Android O（API 级别 26）中，您不能将 getPackageSizeInfo 方法与反射结合使用。以下帖子包含一个代码，可以帮助您在 api 级别 26 及以上的两个应用程序中使用：

https://stackoverflow.com/a/56616172/1939409

Answer 4

按照以下步骤进行

app > src > main >java > 

在此路径下创建三个文件夹

create folder =  "android"> "content" > "pm"

在 pm 文件夹中粘贴此文件以检索所有系统缓存

IPackageDataObserver.java

 package android.content.pm;

import android.os.Binder;
import android.os.IBinder;
import android.os.IInterface;
import android.os.Parcel;
import android.os.RemoteException;

public interface IPackageDataObserver extends IInterface {

public static abstract class Stub extends Binder implements IPackageDataObserver {
    private static final String DESCRIPTOR = "android.content.pm.IPackageDataObserver";
    static final int TRANSACTION_onRemoveCompleted = 1;

    private static class Proxy implements IPackageDataObserver {
        private IBinder mRemote;

        public String getInterfaceDescriptor() {
            return Stub.DESCRIPTOR;
        }

        Proxy(IBinder iBinder) {
            this.mRemote = iBinder;
        }

        public IBinder asBinder() {
            return this.mRemote;
        }

        public void onRemoveCompleted(String str, boolean z) throws RemoteException {
            Parcel obtain = Parcel.obtain();
            try {
                obtain.writeInterfaceToken(Stub.DESCRIPTOR);
                obtain.writeString(str);
                obtain.writeInt(z ? 1 : 0);
                this.mRemote.transact(1, obtain, null, 1);
            } finally {
                obtain.recycle();
            }
        }
    }

    public IBinder asBinder() {
        return this;
    }

    public Stub() {
        attachInterface(this, DESCRIPTOR);
    }

    public static IPackageDataObserver asInterface(IBinder iBinder) {
        if (iBinder == null) {
            return null;
        }
        IInterface queryLocalInterface = iBinder.queryLocalInterface(DESCRIPTOR);
        if (queryLocalInterface == null || !(queryLocalInterface instanceof IPackageDataObserver)) {
            return new Proxy(iBinder);
        }
        return (IPackageDataObserver) queryLocalInterface;
    }

    public boolean onTransact(int i, Parcel parcel, Parcel parcel2, int i2) throws RemoteException {
        String str = DESCRIPTOR;
        if (i == 1) {
            parcel.enforceInterface(str);
            onRemoveCompleted(parcel.readString(), parcel.readInt() != 0);
            return true;
        } else if (i != 1598968902) {
            return super.onTransact(i, parcel, parcel2, i2);
        } else {
            parcel2.writeString(str);
            return true;
        }
    }
}

void onRemoveCompleted(String str, boolean z) throws RemoteException;
}