Android组件ViewStub基本使用方法详解

<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:orientation="vertical"
  tools:context=".MainActivity" >

  <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <Button
      android:id="@+id/showBtn"
      android:layout_width="match_parent"
      android:layout_height="50dip"
      android:layout_weight="1"
      android:text="show" />

    <Button
      android:id="@+id/deleteBtn"
      android:layout_width="match_parent"
      android:layout_height="50dip"
      android:layout_weight="1"
      android:text="delete" />
  </LinearLayout>

  <LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" >

    <ViewStub
      android:id="@+id/viewstub"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout="@layout/next" />
    
  </LinearLayout>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical" >

  <ProgressBar
    android:id="@+id/progressBar1"
    style="?android:attr/progressBarStyleLarge"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

</LinearLayout>

package com.example.android_viewstub1;

import android.os.Bundle;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewStub;
import android.widget.Button;

public class MainActivity extends Activity {

  Button btn1, btn2;
  ViewStub viewStub;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    btn1 = (Button) this.findViewById(R.id.showBtn);
    btn2 = (Button) this.findViewById(R.id.deleteBtn);
    viewStub = (ViewStub) this.findViewById(R.id.viewstub);
    btn1.setOnClickListener(new OnClickListener() {
      @SuppressLint("NewApi")
      @Override
      public void onClick(View arg0) {
        viewStub.setVisibility(View.VISIBLE);
      }

    });
    btn2.setOnClickListener(new OnClickListener() {
      @SuppressLint("NewApi")
      @Override
      public void onClick(View arg0) {
        viewStub.setVisibility(View.INVISIBLE);
      }

    });

  }

}