Reduce screen light on activity

Question

In my application, under certain activity must keep the screen always active (classic keepScreenOn).

In order to reduce a little battery consumption, I would like to implement an energy saving system (similar to the default) type:

After 10 seconds of inactivity, the brightness goes to a minimum (without ever sending the activity paused or similar) to tap the brightness returns to normal and so on ...

is possible to implement such a system? there is an automatic way to calculate the idle time? (because otherwise I would create a cooldwon from 10 to 0, to be carried forward to 10 to each user's tap ...)

Thank you very much

Answer 1

at first write the following permission in your manifest.xml file

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

then, when the 10 seconds pass, run the following code to reduce the Brightness of the device to it's lower level:

Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, 0); //Set the system brightness
android.view.WindowManager.LayoutParams w_lp = getWindow().getAttributes(); //Get the current window attributes
w_lp.screenBrightness = progress / (float)255; //Set the brightness of this window
getWindow().setAttributes(w_lp); //Apply attribute changes to this window

---

and in case you need know how to make sure that it waited for 10 seconds without any user activity, implement the above code the following way:

public class YOUR_ACTIVITY extends Activity {

public static int x = 0; // must be static

@Override
protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       run_thread();
}

private void run_thread(){
    Thread thread = new Thread(new Runnable() {

        @Override
        public void run() {
            while(x < 10){
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                x++;
            }

    Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, 0); //Set the system brightness to it's lowest value
    android.view.WindowManager.LayoutParams w_lp = getWindow().getAttributes(); //Get the current window attributes
    w_lp.screenBrightness = progress / (float)255; //Set the brightness of this window
    getWindow().setAttributes(w_lp); //Apply attribute changes to this window

        }
    });
    thread.start();
}


@Override 
public boolean onTouchEvent(MotionEvent event) {
    x = 0;

    Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, 255); //Set the system brightness back to it's full value
    android.view.WindowManager.LayoutParams w_lp = getWindow().getAttributes(); //Get the current window attributes
    w_lp.screenBrightness = progress / (float)255; //Set the brightness of this window
    getWindow().setAttributes(w_lp); //Apply attribute changes to this window

    return true;
}

Answer 2

I think this is possible using WindowManager.LayoutParams:

WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
layoutParams.screenBrightness = 1F; // or whatever, but a float
getWindow().setAttributes(layoutParams);

The value ranged from 0 (dark) to 1 (bright). A value below 0 resets the default android value.

Answer 3

Use TimerTask to handle the timings

use

@Override
public void onUserInteraction() {
    // TODO Auto-generated method stub
    super.onUserInteraction();

    Log.d(TRCU.LOG_TAG,"User Interaction : "+userInteractionTimeout);

}

to get the user interaction event

And also you can adjust the brightness using

         // Update brightness Instantly
         WindowManager.LayoutParams lp =((Activity) context).getWindow().getAttributes();
         lp.screenBrightness =mCurrentValue/ 255.0f;

         ((Activity) context).getWindow().setAttributes(lp);

Answer 4

Try Using Settings.System.SCREEN_BRIGHTNESS to set system default brightness as:

android.provider.Settings.System.putInt(getContentResolver(),  
android.provider.Settings.System.SCREEN_BRIGHTNESS,brightness /100.0f); // 0-255 

and add these permission's in manifest :

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