控件：拖动条 --- SeekBar（事件处理）

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <SeekBar 
        android:id="@+id/seekbar" 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />
    <TextView 
        android:id="@+id/text"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>
</LinearLayout>

import android.app.Activity;
import android.os.Bundle;
import android.text.method.ScrollingMovementMethod;
import android.widget.SeekBar;
import android.widget.TextView;

public class MySeekBarDemo extends Activity {
    private SeekBar seekbar = null;
    private TextView text = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        super.setContentView(R.layout.main);
        // 取得组件
        this.seekbar = (SeekBar) super.findViewById(R.id.seekbar); 
        // 取得组件
        this.text = (TextView) super.findViewById(R.id.text); 
        // 文本组件的内容可以滚动
        this.text.setMovementMethod(ScrollingMovementMethod.getInstance()); 
        this.seekbar.setOnSeekBarChangeListener(new OnSeekBarChangeListenerImpl());
    }

    private class OnSeekBarChangeListenerImpl implements SeekBar.OnSeekBarChangeListener {
        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {
            MySeekBarDemo.this.text.append("*** 开始拖动，当前值："
                    + seekBar.getProgress() + "\n");
        }
        @Override
        public void onProgressChanged(SeekBar seekBar, int progress,
                boolean fromUser) {
            MySeekBarDemo.this.text.append("*** 正在拖动，当前值："
                    + seekBar.getProgress() + "\n");
        }
        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {
            MySeekBarDemo.this.text.append("*** 停止拖动，当前值："
                    + seekBar.getProgress() + "\n");
        }

    }
}