SeekBar的基本使用方法

a) 什么是SeekBar

b) 使用SeekBar的步骤:

i. 在布局文件当中声明SeekBar: <SekBar android:id=”@+id/seekbarld” android:layout_width=”fill_parent” android:layout_height=”wrap_content”/>

ii. 定义一个OnSeekBarChangeListener: private class SeekBarListener implements SeekBar.OnSeekBarChangeListener{public void onProgressChanged(SeekBar seekBar,int progress,Boolean fromUser){System.out.println(progress);} public void onStartTrackingTouch(SeekBar seekBar){System.out.println(“start:=>”+seekBar.getProgress());} public void onStopTrackingTouch(SeekBar seekBar){System.out.println(“begin:=>”+seekBar.getProgress());}}

iii. 为SeekBar绑定监听器: seekBarSetOnSeekBarChangeListener(new SeekBarListener());

案例项目:

main.xml:

<?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"
    >
<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello"
    />
    <SeekBar
    android:id="@+id/seekBarId"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />
</LinearLayout>
SeekBarJsd.java:

package com.jsd;

import android.app.Activity;
import android.os.Bundle;
import android.widget.SeekBar;

/**
* SeekBar Progress
* @author Administrator
*
*/
public class SeekBarJsd extends Activity {

private SeekBar seekBar = null;

/** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        seekBar = (SeekBar) findViewById(R.id.seekBarId);
        //设置该进度条的最大值,默认情况下为O
        seekBar.setMax(100);
        seekBar.setOnSeekBarChangeListener(seekBarListener);
    }

    /**
     * SeekBarListener
     * 定义一个监听器,该监听器负责监听进度条进度的改变
     */
    private SeekBar.OnSeekBarChangeListener seekBarListener = new SeekBar.OnSeekBarChangeListener() {

    /**
    * 当用户结束对滑块滑动时,调用该方法
    */
  public void onStopTrackingTouch(SeekBar seekBar) {
   // TODO Auto-generated method stub
   System.out.println("stop: > "+seekBar.getProgress());
  }

  /**
   * 当用户开始滑动滑块时调用该方法
   */
  public void onStartTrackingTouch(SeekBar seekBar) {
   // TODO Auto-generated method stub
   System.out.println("start: => "+seekBar.getProgress());
  }

  /**
   * 当进度条发生变化时调用该方法
   */
  public void onProgressChanged(SeekBar seekBar, int progress,
    boolean fromUser) {
   // TODO Auto-generated method stub
   System.out.println(progress);
  }
}

图：
}tu