如何使用android Fragment backstack？

Question

我有四个片段A B C D.当我执行从A跳到B和B到C和C到D.当我按下回车键时，如何得到D到B的结果？

Answer 1

FragmentD：

在FragmentD创建的接口。

OnBackListener mback; 
    public interface OnBackListener { 
     public void onBackClicked(); 
} 

@Override 
    public void onAttach(Activity activity) { 
     try { 
      mback = (OnBackListener) activity; 
     } catch (ClassCastException e) { 
      throw new ClassCastException(activity.toString() 
        + " must implement OnBackListener"); 
     } 
     super.onAttach(activity); 
    } 


public void methodCall() 
    { 
     mback.onBackClicked() 
    } 

然后

父活动

实现我们在FragmentD创建的OnBackListener接口。

public class MyActivity extends FragmentActivity implements OnBackListener { 


// overriding OnBackListener interface method 
     @Override 
      public void onBackClicked() { 

        //calling fragmentb 
      } 

    //Backkey event 
     @Override 
     public void onBackPressed() 
     { 
      super.onBackPressed(); 
      fragmentd.methodCall(); 
     } 

     } 

顺便说一句，你会得到fragmentD的结果到fragmentB。