MyApplication的配置：否则缓存为空

 

 

<application
        android:icon="@drawable/ic_launcher"
        android:name=".MyApplication"
        android:label="@string/app_name" >
        <activity
            android:label="@string/app_name"
            android:name=".MainView" >
            <intent-filter >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>