Android新手必学：调整屏幕亮度的小技巧

在 非 ui 线程 调用 setBrightness

import android.provider.Settings.System

public static void setBrightness(final float fbrightness) {

Log.i( "AdjustBright" , "in setBrightness-1 : " + fbrightness);

act.runOnUiThread(new Runnable() {

public void run() {

WindowManager.LayoutParams lp= act.getWindow().getAttributes(); // 这个值在 0 ～ 1.0 之间， 1 为全亮

if (fbrightness == 0.0 ) {

lp.screenBrightness = 0.005F ;

} else {

lp.screenBrightness = fbrightness;

}

Log.i( "AdjustBright" , "in setBrightness-2 : " + lp.screenBrightness);

act.getWindow().setAttributes(lp);

}

});

}

public static float getBrightness() {

WindowManager.LayoutParams lp= act.getWindow().getAttributes(); //-1 表示使用系统默认值

int br = 255 ;

float fb = 1.0F ;

if (lp.screenBrightness == - 1.0 ) {

try

{

//Get the current system brightness

br = System.getInt(act.getContentResolver(), System.SCREEN_BRIGHTNESS);

fb = br / 255.0F ;

}

catch (android.provider.Settings.SettingNotFoundException e)

{

//Throw an error case it couldn't be retrieved

Log.e( "Error" , "Cannot access system brightness" );

e.printStackTrace();

}

} else {

Log.i( "AdjustBright" , "in getBrightness-1: " + lp.screenBrightness);

fb = lp.screenBrightness;

}

Log.i( "AdjustBright" , "in getBrightness-2: " + fb);

return fb;

}

另外，可通过改系统的亮度设置来改变亮度

android.provider.Settings.System.putInt(act.getContentResolver(), android.provider.Settings.System.SCREEN_BRIGHTNESS_MODE, android.provider.Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);

android.provider.Settings.System.putInt(act.getContentResolver(), android.provider.Settings.System.SCREEN_BRIGHTNESS, brightnessInt); // brightnessInt 值的范围0～255

更改系统亮度需要如下权限：

< uses-permission android:name = "android.permission.WRITE_SETTINGS" ></uses-permission>

参考：