Android清理緩衝功能實現

標籤：android   緩衝   設定   java   

我們都知道在Android的設定->應用程式中可以查看應用程式的相關資訊，其中有一個功能是清除緩衝。

怎麼實現這些功能呢，從Android的setting源碼中可以得到相關資訊。

實現如下：

Java代碼：

package com.wang.clearcache;import java.lang.reflect.Method;import android.os.Bundle;import android.os.RemoteException;import android.app.Activity;import android.content.pm.IPackageStatsObserver;import android.content.pm.PackageManager;import android.content.pm.PackageStats;public class MainActivity extends Activity {private PackageManager pm;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);pm = getPackageManager();//反射try {Method method = PackageManager.class.getMethod("getPackageSizeInfo", new Class[]{String.class,IPackageStatsObserver.class});method.invoke(pm, new Object[]{"com.wang.clearcache",new IPackageStatsObserver.Stub() {@Overridepublic void onGetStatsCompleted(PackageStats pStats, boolean succeeded)throws RemoteException {long cachesize = pStats.cacheSize;long codesize = pStats.codeSize;long datasize = pStats.dataSize;System.out.println("cachesize:"+ cachesize);System.out.println("codesize:"+ codesize);System.out.println("datasize"+ datasize);}}});} catch (Exception e) {e.printStackTrace();}}}

因為得到緩衝資訊需要加入android.permission.GET_PACKAGE_SIZE的許可權

Androidmainifest.xml

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.wang.clearcache"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="17" />    <uses-permission android:name="android.permission.GET_PACKAGE_SIZE"/>    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <activity            android:name="com.wang.clearcache.MainActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>

</pre><pre name="code" class="java">

因為使用在代碼中使用了PackageManager的getPackageSizeInfo這個函數，但是這個方法是不對外公開的函數，所有我們需要使用發射來調用這個函數，在該方法的內部回調了onGetStatsCompleted(PackageStats pStats, boolean succeeded)這個方法，通過該方法的pStats參數可以得到應用的緩衝，資料緩衝，代碼容量緩衝，在使用的過程中需要用到系統的aidl檔案

IPackageStatsObserver：

/***** 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);}

PackageStats：

/* //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;

最後啟動並執行結果：

源碼地址下載：

http://download.csdn.net/detail/wangbiaohome/8026535

Android清理緩衝功能實現