android之SeekBar控件用法详解

package com.example.mars_2400_seekbar;import android.support.v7.app.ActionBarActivity;import android.support.v7.app.ActionBar;import android.support.v4.app.Fragment;import android.app.Activity;import android.os.Bundle;import android.view.LayoutInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.widget.SeekBar;import android.widget.SeekBar.OnSeekBarChangeListener;import android.widget.TextView;import android.os.Build;public class MainActivity extends Activity implements OnSeekBarChangeListener {  private TextView tv;  private SeekBar sb;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    tv = (TextView) findViewById(R.id.textView1);    sb = (SeekBar) findViewById(R.id.seekbar);    sb.setOnSeekBarChangeListener(this);  }  @Override  public void onProgressChanged(SeekBar seekBar, int progress,      boolean fromUser) {    // TODO Auto-generated method stub    tv.setText("Progress is " + progress        + (fromUser ? " Trigger" : " Nontrigger") + " by user.");  } 　　　　@Override  　　　　public void onStartTrackingTouch(SeekBar seekBar) {    　　　　　　// TODO Auto-generated method stub  	　　　　　　System.out.println("onStart-->"+seekBar.getProgress());  　　　　} 　　　　@Override  　　　　public void onStopTrackingTouch(SeekBar seekBar) {    　　　　　　// TODO Auto-generated method stub  	　　　　　　System.out.println("onStop-->"+seekBar.getProgress());  　　　　}  @Override  public boolean onCreateOptionsMenu(Menu menu) {    // Inflate the menu; this adds items to the action bar if it is present.    getMenuInflater().inflate(R.menu.main, menu);    return true;  }}

<?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:id="@+id/textView1"/><SeekBar android:id="@+id/seekbar"  android:layout_width="fill_parent"  android:layout_height="wrap_content"/> </LinearLayout>