Android ActivityGroup和TabActiviy的差异性

AndroidActivityGroup和TabActiviy的差异性

标签：

杂谈

分类： Android技术

1)ActivityGroup

根据SDK的解释其功能“A screen that contains and runs multiple embedded activities.”。翻译成汉语也就是大概"<span style="word-wrap:normal; word-break:normal; line-height:normal; font-weight:normal; font-size:12px; font-family:宋体,微软雅黑,'Lucida Grande',Geneva,Arial,Verdana,'Lucida sans Unicode',Helvetica,sans-serif; color:rgb(112,112,112); border-collapse:separate">在Android中，ActivityGroup类是Activity的容器，可以包含多个嵌套进来的Activitys".<span style="word-wrap:normal; word-break:normal; line-height:normal; font-weight:normal; font-size:12px; font-family:宋体,微软雅黑,'Lucida Grande',Geneva,Arial,Verdana,'Lucida sans Unicode',Helvetica,sans-serif; color:rgb(112,112,112); border-collapse:separate">接下来依然采用源码分析的方式来了解该类的内部实现。

首先，从SDK中和源码中都可以获知，ActivityGroup类的父类是Activity，也就是说二者具有相同的接口和生命周期，同Activity一样，也有onCreate()、onPause()等函数可供我们重载。在ActivityGroup的源码中有成员变量 protected LocalActivityManager mLocalActivityManager; 该变量在ActivityGroup的构造函数中创建并初始化，可见，ActivityGroup的功能实现肯定是要委托给这个对象来完成了。为了给用户开放对此对象的访问，ActivityGroup提供了

              
                
                  
                    public
                  
                
                
                  
                    final
                  
                
                 LocalActivityManager getLocalActivityManager
                
                  (
                
                
                  )
                
                
                  {
                
                
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>return</strong></span> mLocalActivityManager<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span></wbr></wbr>

通过浏览ActivityGroup的源码可以发现，几乎全部是以通过LocalActivityManager对象来完成的具体动作，比如：

                
                  
                    
                      protected
                    
                  
                  
                    
                      void
                    
                  
                   onCreate
                  
                    (
                  
                  Bundle savedInstanceState
                  
                    )
                  
                  
                    {
                  
                  
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>super</strong></span>.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">onCreate</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>savedInstanceState<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
        Bundle states <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> savedInstanceState <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">!=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>null</strong></span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">?</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>Bundle<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> savedInstanceState.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">getBundle</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>STATES_KEY<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">:</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>null</strong></span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
        mLocalActivityManager.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">dispatchCreate</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>states<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span></wbr></wbr></wbr></wbr></wbr>

下面，我们就来看一下LocalActivityManager的源码。在该类中，提供了一个私有类

                
                  
                    
                      private
                    
                  
                  
                    
                      static
                    
                  
                  
                    
                      class
                    
                  
                   LocalActivityRecord 
                  
                    
                      extends
                    
                  
                   Binder 
                  
                    {
                  
                  
<wbr>
        LocalActivityRecord<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,51,153); background-color:transparent">String</span> _id, Intent _intent<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr>
            id <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> _id<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
            intent <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> _intent<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr><wbr><wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>final</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,51,153); background-color:transparent">String</span> id<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>                <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Unique name of this record.</em></span>
<wbr>
        Intent intent<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>                  <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Which activity to run here.</em></span>
<wbr>
        ActivityInfo activityInfo<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>      <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Package manager info about activity.</em></span>
<wbr>
        Activity activity<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>              <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Currently instantiated activity.</em></span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,51,153); background-color:transparent">Window</span> window<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>                  <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Activity's top-level window.</em></span>
<wbr>
        Bundle instanceState<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>           <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Last retrieved freeze state.</em></span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>int</strong></span> curState <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> RESTORED<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>        <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(102,102,102); background-color:transparent"><em>// Current state the activity is in.</em></span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>

用于保存Activity的信息，并提供了

                
                  
                    
                      private
                    
                  
                  
                    
                      final
                    
                  
                   Map
                  
                    <
                  
                  String, LocalActivityRecord
                  
                    >
                  
                   mActivities
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>new</strong></span> HashMap<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&lt;</span>String, LocalActivityRecord<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&gt;</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>private</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>final</strong></span> ArrayList<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&lt;</span>LocalActivityRecord<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&gt;</span> mActivityArray
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>new</strong></span> ArrayList<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&lt;</span>LocalActivityRecord<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&gt;</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span></wbr></wbr></wbr>

采用这样的数据结构用于对所有嵌入的子Activity信息进行保存处理。其中前者用于通过String快速查找，后者用于以数组的方式快速访问，是典型的以空间换时间的的方式。

                
                  
                    
                      public
                    
                  
                  
                    
                      void
                    
                  
                   dispatchCreate
                  
                    (
                  
                  Bundle state
                  
                    )
                  
                  
                    {
                  
                  
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>if</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>state <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">!=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>null</strong></span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>final</strong></span> Iterator<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&lt;</span>String<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">&gt;</span> i <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> state.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">keySet</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span>.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">iterator</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>while</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>i.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">hasNext</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>try</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>final</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,51,153); background-color:transparent">String</span> id <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> i.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">next</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>final</strong></span> Bundle astate <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> state.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">getBundle</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
                    LocalActivityRecord r <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> mActivities.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">get</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>if</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>r <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">!=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>null</strong></span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr>
                        r.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">instanceState</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> astate<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>else</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr>
                        r <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>new</strong></span> LocalActivityRecord<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id, <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>null</strong></span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
                        r.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">instanceState</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> astate<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
                        mActivities.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">put</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id, r<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
                        mActivityArray.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">add</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>r<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>catch</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,51,153); background-color:transparent">Exception</span> e<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr>
……
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr><wbr><wbr>
        mCurState <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> CREATED<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>

从这里我们可以看出，当有一个ActivityGroup被Create的时候，就会有对应的Activity信息被保存到数组中。

当我们调用LocalActivityManager的startActivity()以产生Window的时候，我们也可以看到

                
                  
                    
                      public
                    
                  
                  
                    Window
                  
                   startActivity
                  
                    (
                  
                  
                    String
                  
                   id, Intent intent
                  
                    )
                  
                  
                    {
                  
                  
<wbr>
                   ……
<wbr>
        LocalActivityRecord r <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> mActivities.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">get</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>if</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>r <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">==</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>null</strong></span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr>
            r <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>new</strong></span> LocalActivityRecord<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id, intent<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
            adding <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">=</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,0,102); background-color:transparent"><strong>true</strong></span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr>
                   ……
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; background-color:transparent"><strong>if</strong></span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>adding<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span> <span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">{</span>
<wbr>
            mActivities.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">put</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>id, r<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr>
            mActivityArray.<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,102,51); background-color:transparent">add</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">(</span>r<span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">)</span><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(51,153,51); background-color:transparent">;</span>
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span>
<wbr>
        ……
<wbr><span style="word-wrap:normal; word-break:normal; border:0px; padding:0px; margin:0px; color:rgb(0,153,0); background-color:transparent">}</span></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr></wbr>

有了这个数组，就可以遍历到ActivityGroup中嵌入的Activitys了，从而可以实现ActivityGroup的功能。

以上的分析结果产生的类图如下：

其核心的方面主要体现在：

Intent i = new Intent(MainActivity.this,IndexActivity.class); Window indexWindow = localManager.startActivity(INDEX_ID, i); indexDecorView = indexWindow.getDecorView();

localManager = this.getLocalActivityManager();

然后将view加进你想要用的模块，多个view之间控制好隐藏和显示，就可以了，用activityGroup你会被焦点的问题搞郁闷，我现在一直纠结，如何在window 之间切换，或者request到focus，有这个方面的经验可以谈下。

范例1 使用ActivityGroup来切换Activity和Layout

 在一个主界面中做Activity切换一般都会用TabActivity，使用方便，Activity互相之间相对独立，但是可定制性不强，而且修改起来很麻烦。当然也可以把layout分开，把逻辑代码全写在主界面的逻辑代码中，但是很明显可维护性相当差，这里通过ActivityGroup来解决这个问题。
一、效果图

　　　　要求点击底部不同图片按钮切换不同的Activity，并在中间显示Activity对应的ContentView。

　　二、实现代码

2.1　　layout.xml

<? xmlversion="1.0"encoding="utf-8" ?>
< LinearLayout xmlns:android ="http://schemas.android.com/apk/res/android"
android:layout_width ="fill_parent" android:orientation ="vertical"
android:layout_height ="fill_parent" >
 < LinearLayout android:gravity ="center_horizontal"
android:background ="@drawable/myinfor2" android:layout_width ="fill_parent"
android:layout_height ="wrap_content" >
 < TextView android:id ="@+id/cust_title" android:textColor ="@android:color/white"
android:textSize ="28sp" android:text ="模块1" android:layout_width ="wrap_content"
android:layout_height ="wrap_content" ></ TextView >
 </ LinearLayout >
 
 < ScrollView android:measureAllChildren ="true" android:id ="@+id/containerBody"
android:layout_weight ="1" android:layout_height ="fill_parent"
android:layout_width ="fill_parent" >
 </ ScrollView >
 < LinearLayout android:background ="@android:color/black"
android:layout_gravity ="bottom" android:orientation ="horizontal"
android:layout_width ="fill_parent" android:layout_height ="wrap_content" >
 
 < ImageView android:id ="@+id/btnModule1" android:src ="@android:drawable/ic_dialog_dialer"
android:layout_marginLeft ="7dp" android:layout_marginTop ="3dp"
android:layout_marginBottom ="3dp" android:layout_width ="wrap_content"
android:layout_height ="wrap_content" />
 
 < ImageView android:id ="@+id/btnModule2" android:src ="@android:drawable/ic_dialog_info"
android:layout_marginLeft ="7dp" android:layout_marginTop ="3dp"
android:layout_marginBottom ="3dp" android:layout_width ="wrap_content"
android:layout_height ="wrap_content" />
 
 < ImageView android:id ="@+id/btnModule3" android:src ="@android:drawable/ic_dialog_alert"
android:layout_marginLeft ="7dp" android:layout_marginTop ="3dp"
android:layout_marginBottom ="3dp" android:layout_width ="wrap_content"
android:layout_height ="wrap_content" />
 </ LinearLayout >
</ LinearLayout >

2.2　　TestView.java

public class TestView extends ActivityGroup{ private ScrollViewcontainer = null ;
@Override protected void onCreate(BundlesavedInstanceState){ super .onCreate(savedInstanceState);
 // 隐藏标题栏
requestWindowFeature(Window.FEATURE_NO_TITLE); // 设置视图
setContentView(R.layout.layout); container = (ScrollView)findViewById(R.id.containerBody); // 模块1
ImageViewbtnModule1 = (ImageView)findViewById(R.id.btnModule1); btnModule1.setOnClickListener( new OnClickListener(){ @Override public void onClick(Viewv){ container.removeAllViews(); container.addView(getLocalActivityManager().startActivity( " Module1 " ,
 new Intent(TestView. this ,ModuleView1. class )
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)) .getDecorView()); } }) // 模块2
ImageViewbtnModule2 = (ImageView)findViewById(R.id.btnModule2); btnModule2.setOnClickListener( new OnClickListener(){ @Override public void onClick(Viewv){ container.removeAllViews(); container.addView(getLocalActivityManager().startActivity( " Module2 " ,
 new Intent(TestView. this ,ModuleView2. class )
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)) .getDecorView()); } }); // 模块3
ImageViewbtnModule3 = (ImageView)findViewById(R.id.btnModule3); btnModule3.setOnClickListener( new OnClickListener(){ @Override public void onClick(Viewv){ container.removeAllViews(); container.addView(getLocalActivityManager().startActivity( " Module3 " ,
 new Intent(TestView. this ,ModuleView3. class )
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)) .getDecorView()); } }); } }

　　　　代码说明：

　　　　　　a).　　 ModuleView1、 ModuleView2 、 ModuleView3 分别继承自Activity。

　　　　　　b).　　想动态改变标题可以通过cust_title获取TextView进行设置。

注释：想代码实现将子activity的所用的layout加入到主activty中的layout

　　public class FormActivity extends ActivityGroup {

　　@Override

　　protected void onCreate(Bundle savedInstanceState) {

　　super.onCreate(savedInstanceState);

　　setContentView(R.layout.form);

　　LocalActivityManager m = getLocalActivityManager();

　　Intent intent = new Intent().setClass(this, ContactFieldActivity.class);

　　Window w = m.startActivity("tratat", intent);

　　View v = w.getDecorView();

　　LinearLayout container = (LinearLayout)findViewById(R.id.fieldsContainer);

　　container.addView(v);

　　}

范例2ActivityGroup + GridView 实现Tab分页标签

<a href="http://blog.csdn.net/hellogv/article/details/6057174" style="text-decoration:none; color:rgb(41,113,187)">http://blog.csdn.net/hellogv/article/details/6057174</a>

2) tabActivity

tabActivity继承自Activity，其内部定义好了TabHost，可以通过getTabHost()获取。TabHost 包含了两种子元素：一些可以自由选择的Tab 和tab对应的内容tabContentto，在Layout的<TabHost>下它们分别对应 TabWidget和FrameLayout。 <div>　　使用TabActivity可以让同一个界面容纳更多的内容。我们将按照Standup Timer里的TeamDetailsActivity来讲述TabActivity的使用。在该例中，包含了两个Tab一个用于展示team的统计信息，一个用于展示team所参加的会议的列表（这是一个ListView）。</div> <div> <h2 style="margin:0px; padding:0px; border:0px; list-style:none; color:rgb(0,0,0); line-height:1.5"> 创建Layout </h2> <div style="padding:0px; margin:0px">　　这里需要注意的是不管你是使用TabActivity 还是自定义TabHost，都要求以TabHost作为XML布局文件的根。 <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> <?xml version="1.0" encoding="utf-8"?> <TabHostxmlns:android="http://schemas.android.com/apk/res/android" android:id="@android:id/tabhost"android:layout_width="fill_parent" android:layout_height="fill_parent"> <LinearLayoutandroid:orientation="vertical" android:layout_width="fill_parent"android:layout_height="fill_parent"> <TabWidgetandroid:id="@android:id/tabs" android:layout_width="fill_parent"android:layout_height="wrap_content"/> <FrameLayoutandroid:id="@android:id/tabcontent" android:layout_width="fill_parent"android:layout_height="fill_parent">  <TextViewandroid:id="@+id/no_team_meetings" android:textSize="18sp"android:layout_width="fill_parent" android:layout_height="fill_parent"/> <TextViewandroid:id="@+id/no_team_meeting_stats" android:textSize="18sp"android:layout_width="fill_parent" android:layout_height="fill_parent"/> </FrameLayout> </LinearLayout> </TabHost> </div> </div> </div> <div style="padding:0px; margin:0px">通常我们采用线性布局所以<TabHost> 的子元素是 <LinearLayout>。<TabWidger>对应Tab。<FrameLayout>则用于包含Tab需要展示的内容。需要注意的是<TabWidger> 和<FrameLayout>的Id 必须使用系统id，分别为android:id/tabs 和 android：id/tabcontent 。因为系统会使用者两个id来初始化TabHost的两个实例变量（mTabWidget 和 mTabContent）。</div> <h2 style="margin:0px; padding:0px; border:0px; list-style:none; color:rgb(0,0,0); line-height:1.5"> 编写Java代码</h2> <div style="padding:0px; margin:0px">　　我们可以采用两种方法编写标签页：一种是继承TabActivity ,然后使用getTabHost()获取TabHost对象；第二种方法是使用自定的TabHost在布局文件上<TabHost>的自定义其ID，然后通过findViewById()，方法获得TabHost对象。</div> <div style="padding:0px; margin:0px">　　本文中采用继承TabActivity的方法。</div> <div style="padding:0px; margin:0px"> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> privatevoidcreateTabs() { TabHost tabhost=getTabHost(); tabhost.addTab(tabhost.newTabSpec("stats_tab"). setIndicator(this.getString(R.string.stats)). setContent(createMeetingDetails(team))); tabhost.addTab(tabhost.newTabSpec("meetings_tab"). setIndicator(this.getString(R.string.meetings)). setContent(createMeetingList())); getTabHost().setCurrentTab(0); } </div> </div> Java代码中我们首先需要做的是获取TabHost对象，可以通过TabActivtiy里的getTabHsot（）方法。如果是自定义TabHost，在添加Tabs前应该调用<a href="http://developer.android.com/reference/android/widget/TabHost.html" target="_blank" style="text-decoration:none; color:rgb(41,113,187)">setUp()</a>方法。</div> <div style="padding:0px; margin:0px"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; word-wrap:break-word"></pre> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> mTabHost=(TabHost)findViewById(R.id.tabhost); mTabHost.setup(); mTabHost.addTab(TAB_TAG_1,"Hello, world!","Tab 1"); </div> </div> <pre style="white-space:normal">SDK上的原文：</pre> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; word-wrap:break-word">　　Call setup() before adding tabs if loading TabHost using findViewById().However:You do not need to call setup() after getTabHost() in<code style="padding:0px; margin:0px"><a href="http://developer.android.com/reference/android/app/TabActivity.html" style="text-decoration:none; color:rgb(41,113,187)">TabActivity</a></code>.</pre> 　　接着向TabHost添加tabs.即调用tabHost.addTab(TabSpec) 方法。<a href="http://developer.android.com/reference/android/widget/TabHost.TabSpec.html" target="_blank" style="text-decoration:none; color:rgb(41,113,187)">TabSpec</a>主要包含了setIndicator 和 setContent 方法，通过这两个方法来指定Tab 和 TanContent。</div> <div style="padding:0px; margin:0px">　　TabSpec 通过.newTabSpec(String tag)来创建实例。实例化后对其属性进行设置。setIndicator()设置tab,它有3个重载的函数 </div> <div style="padding:0px; margin:0px"> <ul style="margin:0px 0px 0px 45px; padding:0px; border:0px; list-style-position:initial"> <li style="margin:0px; padding:0px; border:0px; list-style:disc">　public TabHost.TabSpec　setIndicatior(CharSwquence label,Drawable icon).指定tab的标题和图标。</li> <li style="margin:0px; padding:0px; border:0px; list-style:disc">public TabHost.TabSpec (View view)通过View来自定义tab</li> <li style="margin:0px; padding:0px; border:0px; list-style:disc">public TabHost.TabSpec(CharSequence label) 指定tab的标题，此时无图标。</li> </ul> <div style="padding:0px; margin:0px">　 setContent 指定tab的展示内容，它也有3种重载 </div> </div> <div style="padding:0px; margin:0px"> <ul style="margin:0px 0px 0px 45px; padding:0px; border:0px; list-style-position:initial"> <li style="margin:0px; padding:0px; border:0px; list-style:disc">public TabHost.TabSpec setContent(TabHost.TabContentFactory )</li> <li style="margin:0px; padding:0px; border:0px; list-style:disc">public TabHost.TabSpec setContent(int ViewId)</li> <li style="margin:0px; padding:0px; border:0px; list-style:disc">public TabHost.TabSpec setContent(Intent intent)</li> </ul> <div style="padding:0px; margin:0px">　　后两种方法比较后理解一个是通过 ViewId指定显示的内容，如.setContent(R.id.Team_EditText)。第三种则是直接通过Intent加载一个新的Activity页。如.setContent(new Intent(this, MeetingActivity.class)));</div> </div> <div style="padding:0px; margin:0px">　　本例中是通过<a href="http://developer.android.com/reference/android/widget/TabHost.TabContentFactory.html" target="_blank" style="text-decoration:none; color:rgb(41,113,187)">TabContentFactory</a>来指定对应的TabContent。<a href="http://developer.android.com/reference/android/widget/TabHost.TabContentFactory.html" target="_blank" style="text-decoration:none; color:rgb(41,113,187)">TabContentFactory</a>是一个接口，其只包含了一个返回 View 的createTabContent(String tag)方法。</div> <div style="padding:0px; margin:0px"> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> privateTabContentFactory createMeetingDetails(Team team2) { returnnewTabHost.TabContentFactory() { @Override publicView createTabContent(String tag) { 　　　　　　　　　　//设置View setStatsTabContent(); returnfindViewById(R.id.teamStats); } }; } privateTabHost.TabContentFactory createMeetingList() { returnnewTabHost.TabContentFactory() { @Override publicView createTabContent(String tag) { </div> <div style="padding:0px; margin:0px"> 　　　　　　 meetingListAdapter=createMeetingListAdapter(); meetingList.setAdapter(meetingListAdapter); returnmeetingList; } }; } </div> </div> <div style="padding:0px; margin:0px"></div> 事先声明好的</div> <div style="padding:0px; margin:0px"> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> privateListView meetingList=null; privateArrayAdapter<String>meetingListAdapter=null; </div> </div> <div style="padding:0px; margin:0px">我们也可以让TabActivity去实现TabContentFactory 接口</div> <div style="padding:0px; margin:0px"> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> publicclassTabs2extendsTabActivityimplementsTabHost.TabContentFactory </div> </div> 然后在TabActiviy类中实现createTabContent方法</div> <div style="padding:0px; margin:0px"> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <pre style="white-space:normal; padding:0px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> @Override publicView createTabContent(String tag) { finalTextView tv=newTextView(this); tv.setText("Content for tab with tag"+tag); returntv; } </div> </div> </div> setStatsTabContent();方法</div> <div style="padding:0px; margin:0px"> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <img src="http://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif" name="code_img_closed_2fabc5ab-8d5e-4559-b451-8019572189d4" alt="AndroidActivityGroup和TabActiviy的差异性" title="AndroidActivityGroup和TabActiviy的差异性" style="margin:0px; padding:0px 5px 0px 0px; border:0px; list-style:none; vertical-align:middle">setStatsTabContent </div> </div> <div style="padding:0px; margin:0px">　　最后将TabSpec 添加到 TabHost上，即tabHost.addTab(tabSpec)。我们发现TabSpec 的setIndicator 和 setContent 方法返回的都是 TabSpec 自身所以可以使用窜的方式编写代码：</div> <div style="border:1px solid rgb(204,204,204); padding:5px; overflow:auto; font-size:12px; margin:0px; word-break:break-all; font-family:'Courier new'; background-color:rgb(245,245,245)"> <h1 style="margin:0px; padding:0px; border:0px; list-style:none; color:rgb(0,0,0); line-height:1.5"> </h1> </div> <pre style="white-space:normal; padding:0px; font-size:12px; margin-top:0px; margin-bottom:0px; font-family:'Courier new'; word-wrap:break-word"></pre> <div style="padding:0px; margin:0px"> tabhost.addTab(tabhost.newTabSpec("stats_tab") .setIndicator(this.getString(R.string.stats)) .setContent(createMeetingDetails(team))); </div> </div>

 3）两者之间的差异性

在一个主界面中做Activity切换一般都会用TabActivity，使用方便，Activity互相之间相对独立，但是可定制性不强，而且修改起来很麻烦。当然也可以把layout分开，把逻辑代码全写在主界面的逻辑代码中，但是很明显可维护性相当差，这里通过ActivityGroup来解决这个问题

Android ActivityGroup和TabActiviy的差异性

更多文章、技术交流、商务合作、联系博主

微信扫码或搜索：z360901061

微信扫一扫加我为好友

QQ号联系： 360901061

您的支持是博主写作最大的动力，如果您喜欢我的文章，感觉我的文章对您有帮助，请用微信扫描下面二维码支持博主2元、5元、10元、20元等您想捐的金额吧，狠狠点击下面给点支持吧，站长非常感激您！手机微信长按不能支付解决办法：请将微信支付二维码保存到相册，切换到微信，然后点击微信右上角扫一扫功能，选择支付二维码完成支付。

【本文对您有帮助就好】元

2元

5元

10元

20元

自定义

Android ActivityGroup和TabActiviy的差异性

AndroidActivityGroup和TabActiviy的差异性

android

activitygroup

tabactiviy

差异性

杂谈