Android 显示或隐藏标题栏进度条TitleProgressBar

1.新建项目，布局文件如下：activity_main.xml

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:layout_marginLeft="10dp"
     android:orientation="vertical" >

    <Button
         android:id="@+id/btn1"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="显示" />

     <Button
         android:id="@+id/btn2"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="隐藏" />

 </LinearLayout>

2.后台代码如下：MainActivity.java

 package com.example.testdemo;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.Window;
 import android.widget.Button;

 public class MainActivity extends Activity {

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);// 以下两句代码必须写在setContentView之前否则不起作用
         requestWindowFeature(Window.FEATURE_PROGRESS);// 进度指示器功能
         requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); // 不确定的进度
         setContentView(R.layout.activity_main);
         Button btn1 = (Button) findViewById(R.id.btn1);
         Button btn2 = (Button) findViewById(R.id.btn2);
         // 展示标题栏进度条
         btn1.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View v) {
                 setProgressBarVisibility(true);
                 setProgressBarIndeterminateVisibility(true);
             }
         });
         // 隐藏标题栏进度条
         btn2.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View v) {
                 setProgressBarVisibility(false);
                 setProgressBarIndeterminateVisibility(false);
             }
         });
     }
 }

3.效果如如下：