package com.example.seekbar;import android.app.Activity;import android.os.Bundle;import android.widget.ImageView;import android.widget.SeekBar;import android.widget.SeekBar.OnSeekBarChangeListener;public class MainActivity extends Activity { ImageView image; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); image=(ImageView) findViewById(R.id.image); SeekBar seekBar=(SeekBar) findViewById(R.id.seekBar); seekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener(){ @Override public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { image.setImageAlpha(progress); } @Override public void onStartTrackingTouch(SeekBar seekBar) { } @Override public void onStopTrackingTouch(SeekBar seekBar) { } }); }}