如何在对话框显示时保持对上一个活动的editText的关注？

Question

我通过editText创建搜索功能，该功能可以从TextWatcher中侦听密钥。现在我要做的是，当用户键入键@时，它将显示一个对话框并运行recyclerview以显示对话框中的数据。问题是我无法继续从上一个活动输入，因为它已经在后面的堆栈中，前面的是我创建的DialogFragment。

即使对话框片段显示，我如何继续关注editText中的上一个活动？

来自触发对话的活动的示例代码

edit_text_chatbox.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

        }

        @Override
        public void afterTextChanged(Editable s) {
                int lastString = s.length();
                Character character = s.charAt(lastString - 1);
                Log.i("after", "afterTextChanged: "+character);

            if (character.toString().equals("@")){


                AltTaggingDialogFragment dialog = AltTaggingDialogFragment.newInstance();
                dialog.show(getFragmentManager(), "dialog");


            }
        }

我的DialogFragment（AltTaggingDialogFragment）

public class AltTaggingDialogFragment extends DialogFragment{

RecyclerView mRecyclerView;
RecyclerView.Adapter mAdapter_message;
RecyclerView.LayoutManager mLayoutManager;
List<UserFriendList> mUserFriendList;

View view;

EditText friend_tagging;

int friend_count = 7;

@Override
public void onStart() {
    super.onStart();
    Dialog dialog = getDialog();
    Window window = dialog.getWindow();

    int width = ViewGroup.LayoutParams.MATCH_PARENT;
    int height = ViewGroup.LayoutParams.WRAP_CONTENT;
    WindowManager.LayoutParams windowParams = window.getAttributes();
    windowParams.dimAmount = 0.0f;

    dialog.getWindow().setLayout(width,height);

    windowParams.gravity = Gravity.BOTTOM;
    //windowParams.x = width;
    windowParams.y = 90;

    if (friend_count >= 7)
    windowParams.height = (210 * 4) + 150;

    dialog.getWindow().setAttributes(windowParams);

    dialog.getWindow().setSoftInputMode (WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
}


public static AltTaggingDialogFragment newInstance() {
    AltTaggingDialogFragment f = new AltTaggingDialogFragment();
    return f;
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    //inflate layout with recycler view

    view = inflater.inflate(R.layout.fragment_alt_tagging_dialog, container, false);

    friend_tagging = view.findViewById(R.id.friend_tagging);

    mRecyclerView = view.findViewById(R.id.alt_tagging_recycler_view);
    mRecyclerView.setHasFixedSize(true);
    mLayoutManager = new LinearLayoutManager(getActivity());
    mRecyclerView.setLayoutManager(mLayoutManager);

    friend_tagging.requestFocus();
    friend_tagging.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {

        }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

        }

        @Override
        public void afterTextChanged(Editable s) {
            Toast.makeText(getActivity(), "Toast!", Toast.LENGTH_SHORT).show();
        }
    });

    mUserFriendList = new ArrayList<>();
    UserFriendList userFriendList = new UserFriendList();

    super.onViewCreated(view, savedInstanceState);

    for (int i = 0; i < 8; i++) {
        userFriendList.setFirst_name("Mar John");
        userFriendList.setLast_name("Saycon");
        userFriendList.setUsername("MJ");
        mUserFriendList.add(userFriendList);
    }
    mAdapter_message = new AltTaggingAdapter(getActivity(), mUserFriendList);
    mRecyclerView.setAdapter(mAdapter_message);

    return view;

}

}

此图显示了我尝试做的事情。 Sample Image