手柄加載數據隨着片段返回堆棧

Question

我有兩個片段，片段A和片段B.我使用添加片段方法主要活動

String backStateName = fragment.getClass().getName(); 
    FragmentManager fragmentManager = getSupportFragmentManager(); 
    boolean fragmentPopped = fragmentManager.popBackStackImmediate(backStateName, 0); 

    if (!fragmentPopped) { 
     FragmentTransaction ft = fragmentManager.beginTransaction(); 
     ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); 
     ft.add(R.id.frame_container_admin, fragment, backStateName); 
     ft.addToBackStack(backStateName); 
     ft.commit(); 
    } 

在此之後，每當我從PRES片段BI回來要重新加載數據來自服務器。我該如何處理？

Answer 1

在您的活動

創建backstackchange

getSupportFragmentManager().addOnBackStackChangedListener(new FragmentManager.OnBackStackChangedListener() { 
      @Override 
      public void onBackStackChanged() { 
       try { 

        //Get current visible fragment 
        FragmentManager fragmentManager = ((AppCompatActivity) activity).getSupportFragmentManager(); 
        Fragment currentVisibleFragment = fragmentManager.findFragmentById(R.id.container_fragment); 


       if(currentVisibleFragment instanceof FragmentB){ 
        //Cast currentVisibleFragment to Fragment B and call method to request data again. 
        ((FragmentB)currentVisibleFragment).requestData(); 
       } 
       } catch (Exception e) { 
        e.printStackTrace(); 
       } 
      } 
} 

收聽者與您的請求代碼創建在片段B中的請求數據的方法。