How to dim a screen on click of a button in androi

问题:

How do i darken/dim the current screen on click of a button. PLease help me.

回答1:

Here's one solution, though it may not be the best:

create styles.xml under res/values. Add the following code:

<style name="Theme.Translucent" parent="android:Theme">
    <item name="android:windowIsTranslucent">true</item>
    <item name="android:windowBackground">@color/cache_color</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowIsFloating">true</item>
    <item name="android:backgroundDimEnabled">true</item>
 </style>

Note that @color/cache_color is <color name="cache_color">#00000000</color>. Now clicking your custom button should send an intent to an activity (e.g., FooActivity). So declare this in your manifest:

<activity android:name="com.FooActivity" android:theme="@style/Theme.Translucent"></activity>

and voila, the screen is dimmed when your button's listener is called!

回答2:

WindowManager.LayoutParams lparams = getWindow().getAttributes();  
lparams.dimAmount=1.0f; 
dialog.getWindow().setAttributes(lparams);  

The dim amount 0 means no dimming, and the dim amount 1.0f means complete dimming. Any value in between is the corresponding percentage of dim.

Just add this code to the button you want.