屏幕亮度显示的控制

来源：互联网发布：网贷数据交易平台编辑：程序博客网时间：2024/05/21 07:50

1. SeekBarDemo.java

public class SeekBarDemo extends AppCompatActivity {    private SeekBar seekBar = null;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_seek_bar_demo);        this.seekBar = (SeekBar)findViewById(R.id.seekbar);  //取得seekBar        this.seekBar.setMax(100);  //以后计算的时候除以100        this.seekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListenerImpl());    }    private class OnSeekBarChangeListenerImpl implements SeekBar.OnSeekBarChangeListener {        @Override        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {            //正在拖动        }        @Override        public void onStartTrackingTouch(SeekBar seekBar) {            //开始拖动        }        @Override        public void onStopTrackingTouch(SeekBar seekBar) {  //停止拖动            SeekBarDemo.this.setScreenBrightness((float)seekBar.getProgress()/100);  //计算出当前值        }    }    private void setScreenBrightness(float num) {        WindowManager.LayoutParams layoutParams = getWindow().getAttributes();  //取得windows属性        layoutParams.screenBrightness = num;   //num已经除以100        super.getWindow().setAttributes(layoutParams);  //0~1之间    }}

2. activity_seek_bar_demo.xml

<SeekBar    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:id="@+id/seekbar"/><ImageView    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:id="@+id/img"    android:src="@drawable/dog1"    android:layout_below="@+id/seekbar"    android:layout_alignParentLeft="true"    android:layout_alignParentStart="true"    android:layout_marginTop="55dp" />

由于亮度只能在0~1之间的数字表示，所以在每次拖动的时候都要将当前的数字除以100,之后将此内容设置到window的screenBrightness属性中。

2 0