Fragment(碎片)的使用(左标题右内容实现)

res/layout/activity_main.xml的内容：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="horizontal" >    <fragment class="com.example.demofragment.ListFragment"        android:id="@+id/titles"        android:layout_weight="1"        android:layout_width="0px"        android:layout_height="match_parent"/></LinearLayout>

res/layout-land/activity_main.xml的内容：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="horizontal" >        <fragment class="com.example.demofragment.ListFragment"        android:id="@+id/titles"        android:layout_weight="1"        android:layout_width="0px"        android:layout_height="match_parent"/>    <FrameLayout android:id="@+id/detail"        android:layout_weight="2"        android:layout_width="0px"        android:layout_height="match_parent"/>    </LinearLayout>

用于保存标题及内容的Data类：

package com.example.demofragment;/** * @author cjianquan * */public final class Data {//public static final String[] TITLES={"线性布局","表格布局","帧布局","相对布局"};public static final String[] DETAIL= {"线性布局","表格布局","帧布局","相对布局"};}

列表碎片类ListFragment.java：

package com.example.demofragment;import android.app.FragmentTransaction;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.widget.ArrayAdapter;import android.widget.ListView;public class ListFragment extends android.app.ListFragment {boolean dualPane;int curCheckPosition =0 ;public void onActivityCreated(Bundle savedInstanceState){super.onActivityCreated(savedInstanceState);//为列表设置适配器setListAdapter(new ArrayAdapter<String>(getActivity(),android.R.layout.simple_list_item_checked,Data.TITLES));//获取布局文件中添加的FragmentLayout帧布局管理器View detailFrame = getActivity().findViewById(R.id.detail);//判断是否在一屏上同时显示列表和详细内容dualPane = detailFrame != null && detailFrame.getVisibility() == View.VISIBLE;if(savedInstanceState!=null){//更新当前选择的索引位置curCheckPosition = savedInstanceState.getInt("curChoice", 0);}if(dualPane){//如果在一屏上同时显示列表和详细内容//设置列表为单选模式getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);//显示详细内容showDetails(curCheckPosition);}}//保存当前选中的列表项的索引值public void onSaveInstanceSate(Bundle outState){super.onSaveInstanceState(outState);outState.putInt("curChoice", curCheckPosition);}public void onListItemClick(ListView l,View v,int position,long id){showDetails(position);//调用showDetails方法显示　详细内容}void showDetails(int index){//更新保存当前索引位置的变量的值为当前选中值curCheckPosition = index;if(dualPane){//当在一屏上同时显示列表和详细内容时//设置选中列表为选中状态getListView().setItemChecked(index, true);//获取　用于显示详细内容的fragmentDetailFragment details = (DetailFragment)getFragmentManager().findFragmentById(R.id.detail);if(details == null || details.getShownIndex() != index){//创建一个新的DetailFragment实例用于显示当前选择项对应的详细内容details = DetailFragment.newInstance(index);//要在activity中管理fragment，需要使用FragmentManagerFragmentTransaction ft = getFragmentManager().beginTransaction();//替换原来显示的详细内容ft.replace(R.id.detail, details);//设置转换效果ft.setTransitionStyle(FragmentTransaction.TRANSIT_FRAGMENT_FADE);ft.commit();}}else{//在一屏上只能显示列表或详细内容的一个内容时//使用一个新的activity显示详细内容Intent intent = new Intent(getActivity(),MainActivity.DetailActivity.class);intent.putExtra("index",index);startActivity(intent);}}}

详细内容碎片类DetailFragment.java:

package com.example.demofragment;import android.app.Fragment;import android.os.Bundle;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.ScrollView;import android.widget.TextView;public class DetailFragment extends Fragment {public static DetailFragment newInstance(int index){DetailFragment f = new DetailFragment();Bundle bundle = new Bundle();bundle.putInt("index", index);f.setArguments(bundle);return f;}public int getShownIndex(){return getArguments().getInt("index",0);}public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceSate){if(container == null){return null;}ScrollView scroller = new ScrollView(getActivity());TextView text = new TextView(getActivity());text.setPadding(10, 10, 10, 10);text.setTextSize(30);scroller.addView(text);text.setText(Data.DETAIL[getShownIndex()]);return scroller;}}

主入口类及用于显示详细内容的activity: MainActivity.java

package com.example.demofragment;import android.os.Bundle;import android.app.Activity;import android.content.res.Configuration;import android.view.Menu;public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}public static class DetailActivity extends Activity {protected void onCreate(Bundle savedInstanceState){super.onCreate(savedInstanceState);//判断是否为横屏，如果为横屏，则结束当前Activity,准备使用Fragment显示详细内容if(getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE){finish();return;}if(savedInstanceState == null){DetailFragment details = new DetailFragment();details.setArguments(getIntent().getExtras());getFragmentManager().beginTransaction().add(android.R.id.content, details).commit();}}}}

AndroidManifest.xml文件内容如下：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.demofragment"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="14"        android:targetSdkVersion="19" />    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <activity            android:name="com.example.demofragment.MainActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>        <span style="color:#ff0000;"><activity android:name="com.example.demofragment.MainActivity$DetailActivity"            android:label="详细内容"/></span>    </application></manifest>

横屏时的结果图：