Android 8.0的缓存大小和缓存清理接口方法

import android.app.usage.UsageStats;import android.app.usage.UsageStatsManager;import android.content.Context;import android.content.pm.PackageManager;import android.os.Process;import android.os.storage.StorageManager;import java.io.IOException;import java.util.ArrayList;import java.util.Map;import android.app.usage.StorageStats;import android.app.usage.StorageStatsManager;  public static long getCacheSizeByAndroidO(Context mContext, String mPackageName) {    StorageManager storageManager = (StorageManager) mContext.getSystemService(Context.STORAGE_SERVICE);    StorageStatsManager storageStatsManager = (StorageStatsManager) mContext.getSystemService(Context.STORAGE_STATS_SERVICE);    try {      StorageStats storageStats = storageStatsManager.queryStatsForPackage(StorageManager.UUID_DEFAULT, mPackageName, Process.myUserHandle());      return storageStats.getCacheBytes();    } catch (PackageManager.NameNotFoundException e) {      e.printStackTrace();    } catch (IOException e) {      e.printStackTrace();    }    return 0L;  }

        PackageManager mPm = mContext.getPackageManager();        // need android.permission.DELETE_CACHE_FILES        mPm.deleteApplicationCacheFiles(cacheItem.packageName, new IPackageDataObserver.Stub() {          @Override          public void onRemoveCompleted(final String packageName, final boolean succeeded) throws RemoteException {              ///            }          }        });

import com.android.internal.util.Preconditions;import com.android.settings.utils.AsyncLoader;import com.android.settingslib.applications.StorageStatsSource;import com.android.settingslib.applications.StorageStatsSource.AppStorageStats;import java.io.IOException;/** * Fetches the storage stats using the StorageStatsManager for a given package and user tuple. */public class FetchPackageStorageAsyncLoader extends AsyncLoader<AppStorageStats> {  private static final String TAG = "FetchPackageStorage";  private final StorageStatsSource mSource;  private final ApplicationInfo mInfo;  private final UserHandle mUser;  @Override  public AppStorageStats loadInBackground() {    AppStorageStats result = null;    try {      result = mSource.getStatsForPackage(mInfo.volumeUuid, mInfo.packageName, mUser);    } catch (NameNotFoundException | IOException e) {      Log.w(TAG, "Package may have been removed during query, failing gracefully", e);    }    return result;  }========================================================================================package com.android.settings.applications;public class AppStorageSettings extends AppInfoWithHeader  @Override  public void onLoadFinished(Loader<AppStorageStats> loader, AppStorageStats result) {    mSizeController.setResult(result);    updateUiWithSize(result);  }    private void updateUiWithSize(AppStorageStats result) {      } else {      long codeSize = result.getCodeBytes();      long cacheSize = result.getCacheBytes();      long dataSize = result.getDataBytes() - cacheSize;

package com.android.settings.applications;public class AppStorageSettings extends AppInfoWithHeader    implements OnClickListener, Callbacks, DialogInterface.OnClickListener,    LoaderManager.LoaderCallbacks<AppStorageStats> {  private static final String TAG = AppStorageSettings.class.getSimpleName();  private ClearCacheObserver mClearCacheObserver;  @Override  public void onClick(View v) {    // 清理缓存按钮    if (v == mClearCacheButton) {      if (mAppsControlDisallowedAdmin != null && !mAppsControlDisallowedBySystem) {        RestrictedLockUtils.sendShowAdminSupportDetailsIntent(            getActivity(), mAppsControlDisallowedAdmin);        return;      } else if (mClearCacheObserver == null) { // Lazy initialization of observer        mClearCacheObserver = new ClearCacheObserver();      }      mMetricsFeatureProvider.action(getContext(),          MetricsEvent.ACTION_SETTINGS_CLEAR_APP_CACHE);      // 清理缓存      mPm.deleteApplicationCacheFiles(mPackageName, mClearCacheObserver);  class ClearCacheObserver extends IPackageDataObserver.Stub {    public void onRemoveCompleted(final String packageName, final boolean succeeded) {      final Message msg = mHandler.obtainMessage(MSG_CLEAR_CACHE);      msg.arg1 = succeeded ? OP_SUCCESSFUL : OP_FAILED;      mHandler.sendMessage(msg);    }  }

  PackageManager mPm = mContext.getPackageManager();  mPm.getPackageSizeInfo(mPackageName, new IPackageStatsObserver.Stub() {    @Override    public void onGetStatsCompleted(PackageStats pStats, boolean succeeded) throws RemoteException {      cacheTotalSize = pStats.cacheSize + pStats.externalCacheSize;    }  }