android 点击tab页实现当前页面的刷新

最近要实现一个像新浪微博的点击首页实现当前页面的刷新。在网上看了好多文章，最终还是在Google上的http://stackoverflow.com/questions/5487770/get-notified-when-current-tab-is-selected-again得到了启发，终于能够实现此功能，现在就把实现此功能的做法。。

原文是这样说的。。。（此部分代码是Google上的。也就是http://stackoverflow.com/questions/5487770/get-notified-when-current-tab-is-selected-again）

I implemented a TabActivity which implements the OnTabChangeListener. The activity will be notified on tab changes (onTabChanged(String tabId)).

Is it also possible to get notified if the user selects the current tab again?

I would like to use this event to perform a "refresh" of the current tab content instead of providing a refresh button on the tab or in the options menu.

---

That's the way I finally solved the problem - solution hint was in MisterSquonk answer.

(1) Define a OnTabReselectListener which must be implemented by an activity which represents a tab content and which will be notified on reselect events.

/**
 * Interface definition for a callback to be invoked when a current selected tab
 * in a TabHost is selected again.
 */
public interface OnTabReselectListener {

    /**
     * Called when a current visible tab is selected again. Will not be invoked
     * on tab changes.
     */
    void onTabReselect();

}

(2) setOnTouchListener for each tabWidget child in onCreate() of the TabActivity (from MisterSquonk's answer)

for (int i = 0; i < tabWidget.getChildCount(); i++) {
    View v = tabWidget.getChildAt(i);
    v.setOnTouchListener(this);
}

(3) Implement OnTouchListener.onTouch() in the TabActivity. Do some logic to decide if the current tab was selected again and notifiy the tab's activity.

/**
 * @see android.view.View.OnTouchListener#onTouch(android.view.View,
 *      android.view.MotionEvent)
 */
@Override
public boolean onTouch(View v, MotionEvent event) {
    boolean consumed = false;
    // use getTabHost().getCurrentTabView to decide if the current tab is
    // touched again
    if (event.getAction() == MotionEvent.ACTION_DOWN
            && v.equals(getTabHost().getCurrentTabView())) {
        // use getTabHost().getCurrentView() to get a handle to the view
        // which is displayed in the tab - and to get this views context
        View currentView = getTabHost().getCurrentView();
        Context currentViewContext = currentView.getContext();
        if (currentViewContext instanceof OnTabReselectListener) {
            OnTabReselectListener listener = (OnTabReselectListener) currentViewContext;
            listener.onTabReselect();
            consumed = true;
        }
    }
    return consumed;
}

但是我自己做了修改，我用的是tab选项卡布局。。在TabActivity中定义一个接口。

 //用于实现点击首页按钮的接口
  public interface OnTabReselectListener
  {
    public void onTabReselect();

  }

在Tabactivity的onCreate（）方法中

    mainTab = (RadioGroup) findViewById(R.id.main_radio);
    mainTab.getChildAt(0).setOnClickListener(this);//首页按钮点击事件

在TabActivity实现OnClickListener

 @Override
  public void onClick(View v)
  {

   //这两行代码的具体含义正在研究
    View currentView = getTabHost().getCurrentView();
    Context currentViewContext = currentView.getContext();
    if (currentViewContext instanceof OnTabReselectListener)
    {
      OnTabReselectListener listener = (OnTabReselectListener) currentViewContext;
      listener.onTabReselect();
    }
  }

在你想实现刷新的Activity中实现OnTabReselectListener，重写onTabReselect()

 // 实现动态按钮的点击事件
  @Override
  public void onTabReselect()
  {
    listInfo.setSelection(0);//使得当前的listview回到顶部
    refreshInfoData();//异步刷新数据的方法，该方法中通过异步获取数据。显示到布局中
  }

以上不完善的地方就是点击刷新时的顶部不能出现正在加载字样。但功能已实现，，能够刷新数据并显示