一、在Activity的Xml中:
<ImageView
android:id="@+id/image"
android:src="@drawable/bg_login"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<SeekBar
android:id="@+id/seekbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:max="255"
android:progress="255"
android:thumb="@drawable/a"
/>
二、在Activity中:
public class MainActivity extends AppCompatActivity {
private ImageView image;
private SeekBar seekbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}
private void initView() {
image = (ImageView) findViewById(R.id.image);
seekbar = (SeekBar) findViewById(R.id.seekbar);
seekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
//当拖动条的滑块位置发生改变时触发该方法
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
//动态改变图片的透明度
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
// image.setImageAlpha(progress);
}
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
}
}
最简单的实现就这样了,有点小小的问题自己研究吧!!!