獲取屏幕狀態

private boolean isScreenOn () {
    if (android.os.Build.VERSION.SDK_INT >= 20) {
        // I'm counting                                                                                                                
        // STATE_DOZE, STATE_OFF, STATE_DOZE_SUSPENDED                                                                                 
        // all as "OFF"                                                                                                                
        DisplayManager dm = (DisplayManager) getSystemService(Context.DISPLAY_SERVICE);
        Display[] displays = dm.getDisplays();
        for (Display display : displays) {
            if (display.getState () == Display.STATE_ON
                   || display.getState () == Display.STATE_UNKNOWN) {
                return true;
            }
        }
        return false;
    }

    // If you use less than API20:
    PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
    if (powerManager.isScreenOn ()) {
        return true;
    }
    return false;
}