apidemo 学习 android 实现透明activity

<activity            android:name=".app.TranslucentActivity"            android:label="@string/activity_translucent"            android:theme="@style/Theme.Translucent" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.SAMPLE_CODE" />            </intent-filter>        </activity>

    <!-- A theme that has a translucent background.  Here we explicitly specify         that this theme is to inherit from the system's translucent theme,         which sets up various attributes correctly. -->    <style name="Theme.Translucent" parent="android:style/Theme.Translucent">        <item name="android:windowBackground">@drawable/translucent_background</item>        <item name="android:windowNoTitle">true</item>        <item name="android:colorForeground">#fff</item>    </style>

<?xml version="1.0" encoding="utf-8"?><TextView xmlns:android="http://schemas.android.com/apk/res/android"    android:id="@+id/text"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:gravity="center_vertical|center_horizontal"    android:text="@string/translucent_background" />

背景是壁纸的activity

 <activity            android:name=".app.WallpaperActivity"            android:label="@string/activity_wallpaper"            android:theme="@style/Theme.Wallpaper" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.SAMPLE_CODE" />            </intent-filter>        </activity>

 <!-- A theme that has a wallpaper background.  Here we explicitly specify         that this theme is to inherit from the system's wallpaper theme,         which sets up various attributes correctly. -->    <style name="Theme.Wallpaper" parent="android:style/Theme.Wallpaper">        <item name="android:colorForeground">#fff</item>    </style>