Question

我有一个片段类。在该类中，我可以通过单击gridview项来转到另一个片段类。如何按后退按钮进入原班级。

Ex：TheaterFragment类---＆gt; Gridview ----＆gt;点击gridview中的项目-----＆gt; TheaterDetailsFragment

我想按下TheaterDetailsFragment中的后退按钮，再次进入TheaterFragment类。

提前致谢

TheaterFragment类

package com.fortuna.cinemalk;

import java.util.ArrayList;

import android.app.Activity;
import android.app.FragmentManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.GridView;
import android.content.Intent;
import android.widget.AdapterView;



import com.fortuna.cinemalk.adapter.LazyAdapter;
import com.fortuna.cinemalk.model.BaseElement;
import com.fortuna.cinemalk.service.CommonVariable;
import com.fortuna.cinemalk.service.JSONServices;
import com.fortuna.cinemalk.util.Element;

public class TheaterFragment extends Fragment {

    private GridView gridView;

    private ArrayList<BaseElement> filmTheater;
    private LazyAdapter adapter;
    private Activity activity;
    private CommonVariable commonVariable;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

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

        activity = this.getActivity();

        commonVariable = (CommonVariable) activity.getApplication();

        gridView = (GridView) view.findViewById(R.id.gridView1);


        gridView.setOnItemClickListener(new OnItemClickListener() {
               public void onItemClick(AdapterView<?> parent, View v,
                 int position, long id) {


              android.support.v4.app.Fragment detail = new TheaterDetailFragment();
              android.support.v4.app.FragmentManager fragmentManager = getFragmentManager();
              fragmentManager.beginTransaction().replace(R.id.content_frame, detail).commit(); 
               }
              });

            /* FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
        Fragment profileFragment = new MovieDetailFragment();//the fragment you want to show
        profileFragment.setArguments(bundle);
        fragmentTransaction.replace(R.id.shortfilm, profileFragment);//R.id.content_frame is the layout you want to replace
        fragmentTransaction.addToBackStack(null);
        fragmentTransaction.commit();  */

            new BackGround().execute();

        return view;
    }


    public class BackGround extends AsyncTask<Void, Void, Void> {

        @Override
        protected Void doInBackground(Void... params) {

            filmTheater = JSONServices.getTheater();
            return null;
        }

        @Override
        /* check again */
        protected void onPostExecute(Void result) {

            commonVariable.setTheater(filmTheater);

            adapter = new LazyAdapter(filmTheater, activity,
                    Element.THEATER_LIST.getType());

            gridView.setAdapter(adapter);

            super.onPostExecute(result);
        }

        @Override
        protected void onPreExecute() {
            // TODO Auto-generated method stub
            super.onPreExecute();
        }

    }

}

TheaterDetailFragment

package com.fortuna.cinemalk;

import com.fortuna.cinemalk.service.CommonVariable;

import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.GridView;

public class TheaterDetailFragment extends Fragment {

    private Activity activity;


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {



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

        activity = this.getActivity();


        return view;
    }



    }

Answer 1

由于这解决了您的问题，我会将其作为答案发布 -

替换

fragmentManager.beginTransaction()
    .replace(R.id.content_frame, detail)
    .commit();

与

fragmentManager.beginTransaction()
    .replace(R.id.content_frame, detail)
    .addToBackStack("back")     //add this
    .commit();

这是因为（来自API Guides）

执行此类片段事务时，您还可以将其添加到由活动管理的后台堆栈中 - 活动中的每个后台堆栈条目都是发生的片段事务的记录。后向堆栈允许用户通过按“返回”按钮来反转片段事务（向后导航）。

Answer 2

这里有一些文档： http://developer.android.com/training/implementing-navigation/temporal.html

但实质上，在调用commit（）之前添加行

.addToBackStack(null)

null是堆栈的可选名称。

按下后退按钮时转到上一个片段

2 个答案: