AndroidManifest.xml
<activity android:name=".IndexActivity" android:theme="@style/AppThemeIndex">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
styles.xml
<style name="AppThemeIndex" parent="Theme.AppCompat.Light">
<item name="windowNoTitle">true</item>
<item name="windowActionBar">false</item>
<item name="android:windowFullscreen">true</item>
<item name="android:windowBackground">@mipmap/index_0</item>
</style>