Android 进度条显示在标题栏的实现方法

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="horizontal"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 >
<button android:id="@+id/button1" 
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text=" 显示"/>
<button android:id="@+id/button2"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="隐藏"/>
</linearlayout>

package com.imooc.progressbarr;
import android.os.bundle;
import android.app.activity;
import android.view.menu;
import android.view.view;
import android.view.view.onclicklistener;
import android.view.window;
import android.widget.button;
public class mainactivity extends activity {
 private button btn1;
 private button btn2;
 @override
 protected void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  //设置窗口特征：启用显示进度的进度条
  requestwindowfeature(window.feature_progress);
   //设置窗口特征：启用不显示进度的进度条
  requestwindowfeature(window.feature_indeterminate_progress);
  setcontentview(r.layout.activity_main);
  button btn1=(button)findviewbyid(r.id.button1);
  button btn2=(button)findviewbyid(r.id.button2);
  btn1.setonclicklistener(new onclicklistener(){
   @override
   public void onclick(view v) {
    // todo auto-generated method stub
    //显示不带进度的进度条
    setprogressbarindeterminatevisibility(true);
    //显示不带进度的进度条
    setprogressbarvisibility(true);
    //设置进度条的进度
    setprogress(4500);
   } 
  });
  btn2.setonclicklistener(new onclicklistener(){
   @override
   public void onclick(view v) {
    // todo auto-generated method stub
    //隐藏不带进度的进度条
    setprogressbarindeterminatevisibility(false);
    //隐藏带进度的进度条
    setprogressbarvisibility(false);
   } 
  });
 }
 @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;
 }
}