方法一:
通过Theme.Translucent
@android:style/Theme.Translucent
@android:style/Theme.Translucent.NoTitleBar
@android:style/Theme.Translucent.NoTitleBar.Fullscreen
只需要在Manifest中需要透明的Activity内设置theme为以上任意一个就可以了
<activity
android:name="com.vixtel.simulate.MainApp"
android:configChanges="keyboardHidden|orientation"
android:label="@string/app_name"
android:screenOrientation="portrait"
android:theme="@android:style/Theme.Translucent.NoTitleBar" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
方法二:
自定义style,就像自定义Dialog的style一样,在res-values-color.xml中添加透明颜色值:
<?xml version="1.0" encoding="UTF-8"?>
<resources>
<color name="transparent">#0000</color>
</resources>
在res-values-styles.xml中添加如下:
<style name="myTransparent">
<item name="android:windowBackground">@color/transparent</item>
<item name="android:windowNoTitle">true</item>
<item name="android:windowIsTranslucent">true</item>
<item name="android:windowAnimationStyle">@android:style/Animation.Translucent</item>
</style>
在Manifest中中需要透明的Activity内设置theme为我们自定义的即可
android:theme="@style/myTransparent"
![Android设置Activity背景为透明style Android设置Activity背景为透明style](https://image.shishitao.com:8440/aHR0cHM6Ly93d3cuaXRkYWFuLmNvbS9nby9hSFIwY0RvdkwybHRaeTVpYkc5bkxtTnpaRzR1Ym1WMEx6SXdNVFF3TnpJMU1UYzBPVEF3TnpFNFAzZGhkR1Z5YldGeWF5OHlMM1JsZUhRdllVaFNNR05FYjNaTU1rcHpZakpqZFZrelRtdGlhVFYxV2xoUmRtSlhSbXROVkdzMFQxRTlQUzltYjI1MEx6VmhOa3cxVERKVUwyWnZiblJ6YVhwbEx6UXdNQzltYVd4c0wwa3dTa0pSYTBaRFRVRTlQUzlrYVhOemIyeDJaUzgzTUM5bmNtRjJhWFI1TDFOdmRYUm9SV0Z6ZEE9PQ%3D%3D.jpg?w=700&webp=1)
转自:http://blog.csdn.net/mad1989/article/details/38122713