java - 从 ViewPager Fragment 监听 DialogFragment dismiss 事件

Question

有很多(重复的)问题和答案可用，我几乎经历了所有问题和答案，但都失败了。引用this问题，我最近做了一些改变。

简介:在我的应用程序中，MainActivity 包含 Fragment View Pager 和 FrangmentA、B 和 C。FrangmentA 在 Clik 上显示 DialogFragment CDialog。关闭 CDialog 后，我需要调用 FragmentA 的 doReload()，这在此处没有发生。

主要 Activity

protected void onCreate(Bundle savedInstanceState){
                          ...

            mSectionsPageAdapter = new FragmentAdapter(getSupportFragmentManager());
            mViewPager = (ViewPager) findViewById(R.id.container);
            setupViewPager(mViewPager);
            TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
            tabLayout.setupWithViewPager(mViewPager);
            int defaultValue = 0;
            int page = getIntent().getIntExtra("One", defaultValue);
            mViewPager.setCurrentItem(page);
    }

    private void setupViewPager(ViewPager viewPager)
        {
            FragmentAdapter adapter = new 
            FragmentAdapter(getSupportFragmentManager());
            adapter.addFragment(new FragmentA(), "FragA");
            adapter.addFragment(new FragmentB(), "FragB");
            adapter.addFragment(new FragmentC(), "FragC");
            viewPager.setAdapter(adapter);
        }

fragment A

    public class FragmentA extends Fragment implements CDialog.Dismissed{
    @Override
        public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    ...
    button.setOnClickListener(new View.OnClickListener() {
                public void onClick(View view) {
                   FragmentManager fm =  getActivity().getFragmentManager();
                    DialogFragment f = new CDialog();
                    f.show(fm, "CDialog");
                    }
            });

 @Override
    public void dialogDismissed() {
        Log.e(DFD_1, "dialogDismiss Called" );// <-- This is not working*
        doReload();
    }
    }

和对话

public  class CDialog extends DialogFragment{

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
                                    ....
                      return v;
   }
  @Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
           ...

            dfd_1.setOnClickListener(
            new View.OnClickListener() {
                public void onClick(View v) {
                        getDialog().dismiss(); //<--when this happens*
                    }
            });

}
    @Override
        public void onDismiss(DialogInterface dialog) {
            if (getActivity() != null && getActivity() instanceof Dismissed) {
                ((Dismissed) getActivity()).dialogDismissed();
            }
            super.onDismiss(dialog);
        }

        public interface Dismissed {
            public void dialogDismissed();  //<-- FragmentA implements this 
        }
}

Answer 1

您始终可以直接回调到您的 Fragment 本身。

第一步，使用setTargetFragment()设置targetFragment:

DialogFragment#setTargetFragment(Fragment fragment, int requestCode);

我是这样做的:

public void showDialogFragment(Fragment targetFragment, AppCompatDialogFragment appCompatDialogFragment, int requestCode) {
    FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
    fragmentTransaction.setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out);
    appCompatDialogFragment.setTargetFragment(targetFragment, requestCode);
    fragmentTransaction.add(appCompatDialogFragment, appCompatDialogFragment.getClass().getSimpleName());
    fragmentTransaction.commitAllowingStateLoss();
}

然后调用此方法打开对话框 fragment :

public static final int RC_CDIALOG = 111;

button.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
               showDialogFragment(FragmentA.this, new CDialog(), RC_CDIALOG);
            }
        });

然后，在您的 DialogFragment 的 onDismissListener() 中，加入如下代码:

@Override
public void onDismiss(DialogInterface dialog) {
    super.onDismiss(dialog);

    if (getTargetFragment() instanceof FragmentA)
        ((FragmentA) getTargetFragment()).doReload();

}

你这样做的是:

显示对话框 fragment “CDialog”并告诉它您的目标 fragment 是“FragmentA”，您可以使用它的引用以防您与它有关系。在您的情况下，您必须调用 doReload();