片段

Question

我在另一个片段中有3个片段，我在点击按钮时在片段之间切换 我的问题是，当我按下后退按钮时，片段被隐藏，我需要再次按后退按钮退出片段 如何解决这个问题？

这是我的片段

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    if (rootView != null) {
        ViewGroup parent = (ViewGroup) rootView.getParent();
        if (parent != null)
            parent.removeView(rootView);
    }
    try {
        rootView = inflater.inflate(R.layout.barber_descrption_layout_fragment, container, false);
    } catch (InflateException e) {
    }
    context = getActivity();

    linearLayoutMain = (LinearLayout) rootView.findViewById(R.id.mainfrag);
    myTextView_appointment = (MyTextView) rootView.findViewById(R.id.text_appi);
    myTextView_map = (MyTextView) rootView.findViewById(R.id.textView2);
    myTextView_images = (MyTextView) rootView.findViewById(R.id.img);
    rate_btn = (LinearLayout) rootView.findViewById(R.id.rate_button);
    rate_btn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            ShowRateDialog(context);
        }
    });

    Fragment fragment = new Appointment_Fragment();
    Bundle bundle = new Bundle();
    fragment.setArguments(bundle);
    getActivity().getSupportFragmentManager().beginTransaction()
            .replace(R.id.mainfrag, fragment, fragment.getClass().getSimpleName()).addToBackStack(null).commit();
    linearLayoutMain.setBackground(getResources().getDrawable(R.drawable.blue_boarder_map));
    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);

    linearLayoutMain.setLayoutParams(params);
    //////////////////////////////////
    myTextView_appointment.setBackground(getResources().getDrawable(R.drawable.appi_color));
    myTextView_appointment.setTextColor(getResources().getColor(R.color.white));
    /////////////////////////
    myTextView_appointment.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            myTextView_appointment.setBackground(getResources().getDrawable(R.drawable.appi_color));
            myTextView_appointment.setTextColor(getResources().getColor(R.color.white));
            myTextView_map.setTextColor(getResources().getColor(R.color.blue_color));
            myTextView_map.setBackground(getResources().getDrawable(R.drawable.map_color_white));
            myTextView_images.setTextColor(getResources().getColor(R.color.blue_color));
            myTextView_images.setBackground(getResources().getDrawable(R.drawable.blue__white));
            linearLayoutMain.setBackgroundColor(getResources().getColor(R.color.white));

            Fragment fragment = new Appointment_Fragment();
            Bundle bundle = new Bundle();
            fragment.setArguments(bundle);
            getActivity().getSupportFragmentManager().beginTransaction()
                    .replace(R.id.mainfrag, fragment, fragment.getClass().getSimpleName()).addToBackStack(null).commit();
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            params.setMargins(0, 0, 0, 0);
            linearLayoutMain.setLayoutParams(params);

        }
    });
    myTextView_map.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            myTextView_map.setBackground(getResources().getDrawable(R.drawable.map_color));
            myTextView_map.setTextColor(getResources().getColor(R.color.white));
            myTextView_appointment.setTextColor(getResources().getColor(R.color.blue_color));
            myTextView_appointment.setBackground(getResources().getDrawable(R.drawable.apii_color_white));
            myTextView_images.setTextColor(getResources().getColor(R.color.blue_color));
            myTextView_images.setBackground(getResources().getDrawable(R.drawable.blue__white));
            linearLayoutMain.setBackground(getResources().getDrawable(R.drawable.blue_boarder_map));
            Fragment fragment = new MapFragment_Barber();
            Bundle bundle = new Bundle();
            fragment.setArguments(bundle);
            getActivity().getSupportFragmentManager().beginTransaction()
                    .replace(R.id.mainfrag, fragment, fragment.getClass().getSimpleName()).addToBackStack(null).commit();
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            params.setMargins(40, 40, 40, 40);
            linearLayoutMain.setLayoutParams(params);

        }
    });

    myTextView_images.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            myTextView_images.setBackgroundColor(getResources().getColor(R.color.blue_color));
            myTextView_images.setTextColor(getResources().getColor(R.color.white));
            myTextView_map.setTextColor(getResources().getColor(R.color.blue_color));
            myTextView_map.setBackground(getResources().getDrawable(R.drawable.map_color_white));

            myTextView_appointment.setTextColor(getResources().getColor(R.color.blue_color));
            myTextView_appointment.setBackground(getResources().getDrawable(R.drawable.apii_color_white));
            linearLayoutMain.setBackgroundColor(getResources().getColor(R.color.white));
            Fragment fragment = new BarberImage();
            Bundle bundle = new Bundle();
            fragment.setArguments(bundle);
            getActivity().getSupportFragmentManager().beginTransaction()
                    .replace(R.id.mainfrag, fragment, fragment.getClass().getSimpleName()).addToBackStack(null).commit();

            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            params.setMargins(40, 40, 40, 0);
            linearLayoutMain.setLayoutParams(params);
        }
    });

    return rootView;
}

我需要这样当我按下后退按钮时，我会在第一次点击时退出片段而不需要多次点击。

Answer 1

按照这个。使用onBackPressed()在Fragment上实施Abstract Class功能的绝佳示例。

1）创建一个抽象类 -

import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;

public abstract class BackableFragment extends Fragment implements View.OnKeyListener {

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        view.setFocusableInTouchMode(true);
        view.requestFocus();
        view.setOnKeyListener(this);
    }

    @Override
    public boolean onKey(View v, int keyCode, KeyEvent event) {
        if (event.getAction() == KeyEvent.ACTION_UP) {
            if (keyCode == KeyEvent.KEYCODE_BACK) {
                onBackButtonPressed();
                return true;
            }
        }

        return false;
    }

    public abstract void onBackButtonPressed();
}

2）将Abstract Class实施到Fragment -

public class Appointment_Fragment extends BackableFragment {

public static final String CLASS_NAME = "Appointment_Fragment";
public FragmentChangeListener fragmentChangeListener;

    ...

    @Override
    public void onBackButtonPressed() {
        fragmentChangeListener.OnFragmentChange(CLASS_NAME);
    }

    ...
}

3）制作一个名为interface的{​​{1}}。

FragmentChangeListener

4）在interface FragmentChangeListener{ public void onFragmentChange(String fragmentName); } -

上实施

activity

多数民众赞成。 Reference

Answer 2

如果您在片段中，请转到childFragmentManager

android.support.v4.app.FragmentManager fm = getChildFragmentManager();

onBackPress上的

只会杀死父片段