Java 无法将IPackageStatsObserver解析为类型（Android）

我想计算使用该设备的所有缓存的总和。为此，我得到一个编译时间错误：

IPackageStatsObserver cannot be resolved to a type

我在代码中已两次提到此错误：

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;
}

public long totalCacheSize（）{
totalSize=0；
PackageManager PackageManager=getApplicationContext（）.getPackageManager（）；
/*列表包=packageManager
.getInstalledPackages（PackageManager.GET_活动）*/
//PackageManager.GET_元数据
列表包=packageManager
.getInstalledPackages（PackageManager.GET_元数据）；
对于（int i=0；i

IPackageStatsObserver

在android SDK中不可用。可能使用

class.forName（）

加载存根类，查找默认构造函数并调用它以获取

存根的新实例。但是我该怎么编码呢，我对它一无所知

救命
 您需要在项目中添加和。
要解决问题，请执行以下步骤：

Android Studio


右键单击您的项目新建>文件夹>AIDL文件夹
按Finish
右键单击
aidl
folderNew>Package
插入android.content.pm

并按OK

下载

将aidl文件复制到

android.content.pm

包中

构建>重建项目

Eclipse

• 右键单击

  src

  folderNew>Package
• 插入

  android.content.pm

• 按Finish
• 下载
• 将aidl文件复制到

  android.content.pm

  包中
• 选择

  totalCacheSize

  所在的类，然后选择Source>organizeimports

---

更新

在Android O（API级别26）中，您不能对reflaction使用

getPackageSizeInfo

方法。以下帖子包含一段代码，可帮助您处理api级别26以下和以上的应用程序：

遵循以下步骤

app > src > main >java > 

在此路径中创建三个文件夹

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;
}

---

我尝试使用他们的代码getPackageSizeInfo.invoke（packageManager，“com.android.mms”，新的IPackageStatsObserver.Stub（）{//error仍然是相同的错误