Android屏幕亮度调节相关源码

如下代码内容是关于Android屏幕亮度调节相关的代码。

public static boolean isAutoBrightness(ContentResolver aContentResolver) {
boolean automicBrightness = false;
try {
automicBrightness = Settings.System.getInt(aContentResolver,
Settings.System.SCREEN_BRIGHTNESS_MODE) == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC;
} catch (SettingNotFoundException e) {
e.printStackTrace();
}
return automicBrightness;
}

然后就是要觉得当前的亮度了，这个就比较纠结了：

public static int getScreenBrightness(Activity activity) {
int nowBrightnessValue = 0;
ContentResolver resolver = activity.getContentResolver();
try {
nowBrightnessValue = android.provider.Settings.System.getInt(
resolver, Settings.System.SCREEN_BRIGHTNESS);
} catch (Exception e) {
e.printStackTrace();
}
return nowBrightnessValue;
}

那如何修改屏幕的亮度呢？

public static void setBrightness(Activity activity, int brightness) {
WindowManager.LayoutParams lp = activity.getWindow().getAttributes();
activity.getWindow().setAttributes(lp);

}

那么，能设置了，但是为什么还是会出现，设置了，没反映呢？嘿嘿，那是因为，开启了自动调节功能了，那如何关闭呢？这才是最重要的：

public static void stopAutoBrightness(Activity activity) {
Settings.System.putInt(activity.getContentResolver(),
Settings.System.SCREEN_BRIGHTNESS_MODE,
Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);
}

能开启，那自然应该能关闭了哟哟，那怎么关闭呢？很简单的：

public static void startAutoBrightness(Activity activity) {
Settings.System.putInt(activity.getContentResolver(),
Settings.System.SCREEN_BRIGHTNESS_MODE,
Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC);
}

至此，应该说操作亮度的差不多都有了，结束！哎，本来认为是应该结束了，但是悲剧得是，既然像刚才那样设置的话，只能在当前的activity中有作用，一段退出的时候，会发现毫无作用，悲剧，原来是忘记了保存了。汗！

public static void saveBrightness(ContentResolver resolver, int brightness) {
Uri uri = android.provider.Settings.System
.getUriFor("screen_brightness");
android.provider.Settings.System.putInt(resolver, "screen_brightness",
brightness);
resolver.notifyChange(uri, null);
}