Android Fragment功能的例子

实现的功能很简单，也是最基本的，上下分别是两个Fragment，上面的Fragment中是一个listview，当点击item时，下面的Fragment显示对应的文字详细信息

具体的实现步骤如下：
①创建工程FragmentExam，目录视图如下(把之前的FragmentPreference的demo也加到了一起)：
②main.xml文件布局，垂直方向上两个Fragment，用<Fragment>标签声明

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical"
    android:background="#7ecef4">
        <fragment
            android:name="com.example.fragementexam.FragementList"
            android:id="@+id/frag_list"
            android:layout_width="fill_parent"
            android:layout_height="0dp"
            android:layout_weight="2"/>
        <fragment
            android:name="com.example.fragementexam.FragementDetails"
            android:id="@+id/frag_detail"
            android:layout_width="fill_parent"
            android:layout_height="0dp"
            android:layout_weight="1"/>
</LinearLayout>

③FragmentList.java的代码,它继承了ListFragment，注意在onCreateView方法中使用inflater的inflate方法将布局页面引进：

package com.example.fragementexam;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.ListFragment;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class FragementList extends ListFragment {
        private String[] values = new String[] { "侏儒", "人类", "暗夜精灵", "矮人", "德莱尼",
                        "狼人" };
        private int[] images = new int[] { R.drawable.gnome,
                        R.drawable.human, R.drawable.nightelf,
                        R.drawable.dwarf, R.drawable.draenei,
                        R.drawable.werewolf };

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

                return inflater.inflate(R.layout.frag_list, container, false);
        }

        @Override
        public void onActivityCreated(Bundle savedInstanceState) {
                super.onActivityCreated(savedInstanceState);

                List<Map<String, Object>> listItems = new ArrayList<Map<String, Object>>();
                for (int i = 0; i < values.length; i++) {
                        Map<String, Object> listItem = new HashMap<String, Object>();
                        listItem.put("values", values);
                        listItem.put("images", images);
                        listItems.add(listItem);
                }
                SimpleAdapter adapter = new SimpleAdapter(getActivity(), listItems,
                                R.layout.list_item, new String[] { "values", "images" },
                                new int[] { R.id.txt_title, R.id.img });
                setListAdapter(adapter);

        }

        @Override
        public void onListItemClick(ListView l, View v, int position, long id) {
                // String item = (String) getListAdapter().getItem(position);
                FragementDetails frag = (FragementDetails) getFragmentManager()
                                .findFragmentById(R.id.frag_detail);
                if (frag != null && frag.isInLayout()) {
                        switch (position) {
                        case 0:
                                frag.setText(getString(R.string.Gnome));
                                break;
                        case 1:
                                frag.setText(getString(R.string.Human));
                                break;
                        case 2:
                                frag.setText(getString(R.string.NightElf));
                                break;
                        case 3:
                                frag.setText(getString(R.string.Dwarf));
                                break;
                        case 4:
                                frag.setText(getString(R.string.Draenei));
                                break;
                        case 5:
                                frag.setText(getString(R.string.Werewolf));
                                break;
                        }
                }

                Log.i("PDA", "position = " + position);
        }

}

④FragementDetails.java的代码，这个比较简单，里面有一个设置TextView内容的方法，其布局页面也仅仅是一个TextView

package com.example.fragementexam;

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class FragementDetails extends Fragment {

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                        Bundle savedInstanceState) {
                // TODO Auto-generated method stub
                return inflater.inflate(R.layout.frag_detail, container,false);
        }

        public void setText(String item){
                TextView txt = (TextView) getView().findViewById(R.id.txt_detail);
                txt.setText(item);
        }

}

其他的部分就是一些数组，String的定义了，这个demo虽然简单，却将Android Fragment方面常用到的做了一个综述，如果自己写明白了这个的话，今后遇到类似的项目应该要好应付的多