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MainActivity如下:

package cc.testsimplefragment2;import android.app.Activity;import android.os.Bundle;/** * Demo描述: * Fragment使用示例 *  * 备注说明: * 1 在main.xml中存在一个Fragment即 *   TitleListFragment.用它来显示Titles * 2 点击TitleListFragment中的某个条目的时候 *   判断的横竖屏 *   2.1 若是横屏,则用另外一个Fragment显示详细信息 *   2.2 若是竖屏,则启动另一个Activity显示详细信息 *       2.2.1 在该Activity中动态添加一个Fragment显示详细信息 *  * 参考文档: * 1 http://blog.csdn.net/t12x3456/article/details/8120309 * 2 http://blog.csdn.net/nkmnkm/article/category/958669/5 * 3 http://blog.csdn.net/xiaanming/article/details/9254749 *   Thank you very much * */public class MainActivity extends Activity {	@Override	public void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.main); 	}		@Override	protected void onSaveInstanceState(Bundle outState) {		super.onSaveInstanceState(outState);		System.out.println("---> MainActivity onSaveInstanceState()");	}}

package cc.testsimplefragment2;import android.app.FragmentTransaction;import android.app.ListFragment;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.widget.ArrayAdapter;import android.widget.ListView;public class TitleListFragment extends ListFragment {	//当前是否为横屏	private boolean currentIsLand;	//当前选中位置	private int currentCheckedPosition = -1; 	private final String currentCheckedKey="currentChecked";		//每次重绘Fragment时都会调用该onActivityCreated()方法	@Override	public void onActivityCreated(Bundle savedInstanceState) {		super.onActivityCreated(savedInstanceState);        System.out.println("---> onActivityCreated");		//设置适配器		ArrayAdapter
   
     arrayAdapter=		new ArrayAdapter
    
     (getActivity(),android.R.layout.simple_list_item_checked, Data.TITLES);		setListAdapter(arrayAdapter); 		//判断当前是否为横屏		//注意方式:		//先利用getActivity()找到该Fragment隶属于的Activity,再findViewById()		//为什么要这么判断是否是横屏呢?		//因为横屏的时候会去读取layout-land下的main.xml布局文件		//在该布局文件下有一个RelativeLayout,其id为containerRelativeLayout		//所以,若能找到它那么就可以表明当前是横屏		View containerView = getActivity().findViewById(R.id.containerRelativeLayout);		currentIsLand = containerView != null && containerView.getVisibility() == View.VISIBLE; 		if (savedInstanceState != null) {			currentCheckedPosition = savedInstanceState.getInt(currentCheckedKey, 0);			getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE); 			getListView().setItemChecked(currentCheckedPosition, true); 			System.out.println("---> onActivityCreated() currentCheckedPosition="+currentCheckedPosition);		}else{			System.out.println("---> onActivityCreated() savedInstanceState == null ");		}		if (currentIsLand) { 			//设置ListView为单选模式			getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE); 			showDetailContent(currentCheckedPosition); 		}	}		@Override	public void onStart() {		super.onStart();		System.out.println("---> onStart");	}		//处理手机一直在竖屏时:	//点击标题,跳转后,再按下back键的情况	@Override	public void onResume() {		super.onResume();		System.out.println("---> onResume");		if (!currentIsLand) {			getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);			//currentCheckedPosition默认为-1			//所以在第一次时不选择任何一个			if (currentCheckedPosition>=0) {				getListView().setItemChecked(currentCheckedPosition, true);			}		}	}	//保存数据	//Fragment被系统或者某些内存清理,或者横竖屏切换而被销毁时	//将会触发onSaveInstanceState(Bundle savedInstanceState):	//Called to ask the fragment to save its current dynamic state,	//so it can later be reconstructed in a new instance of its process is restarted.	//然后调用onActivityCreated()生命周期方法,重绘Fragment    	//存在的疑问:	//在手机一直竖屏的情况下,点击TitleListFragment的条目	//为什么会执行该onSaveInstanceState()方法和MainActivity的	//onSaveInstanceState()方法	@Override	public void onSaveInstanceState(Bundle bundle) {		super.onSaveInstanceState(bundle);		bundle.putInt(currentCheckedKey, currentCheckedPosition);		System.out.println("---> onSaveInstanceState()");		System.out.println("---> onSaveInstanceState() currentCheckedPosition="+currentCheckedPosition);	}		//点击ListFragment上的某个条目时调用	@Override	public void onListItemClick(ListView l, View v, int position, long id) {		showDetailContent(position); 	}	//显示详细内容	private void showDetailContent(int index) {		//保存当前被选中的位置		currentCheckedPosition=index;		//横屏时		if (currentIsLand) {			//1  先设置TitleListFragment			//  改变ListFragment的index位置被选中			getListView().setItemChecked(index, true); 			//2  再设置DetailFragment			//  利用FragmentManager判断在某个容器(container)中是否有一个DetailFragment			//  如果没有或在有的情况下其CheckedIndex不等于当前被选中的index			//  则进行replace()操作			DetailFragment detailFragment = 			(DetailFragment) getFragmentManager().findFragmentById(R.id.containerRelativeLayout); 			if (detailFragment == null || detailFragment.getCheckedIndex() != index) {				//生成新的Fragment.				detailFragment = DetailFragment.newInstance(index);				//开始Fragment的事务Transaction				//因为在这个事务中执行了replace()操作,所以会将该				//detailFragment attach到activity,按照生命周期				//的顺序必然会调用DetailFragment的onCreateView().				//更加白话地说:其实相当于我们先做了一些内在的东西,再做了外在的东西.				//什么意思呢?				//内在的部分:我们先new了一个DetailFragment,并且为这个DetailFragment				//设置了一些参数.				//这些都体现在了DetailFragment.newInstance(index)方法中				//外在的部分:利用replace()将该DetailFragment attach到activity				//这些都体现在了DetailFragment的onCreateView()方法中.所以在				//该方法中我们可以去取为此DetailFragment设置的参数.				//即方法getCheckedIndex()				FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();				//替换容器(container)原来的Fragment				fragmentTransaction.replace(R.id.containerRelativeLayout, detailFragment); 				//设置转换效果				fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE); 				//提交事务				fragmentTransaction.commit(); 			}        //竖屏时		} else { 			Intent intent = new Intent(getActivity(),DetailActivity.class);			intent.putExtra("index", index); 			startActivity(intent); 		}	}}
    
   

package cc.testsimplefragment2;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 {	//往ScrollView中添加一个TextView然后将其返回	@Override	public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {		if (container == null) {			return null;		}		ScrollView scrollView = new ScrollView(getActivity()); 		TextView textView = new TextView(getActivity()); 		textView.setPadding(10, 10, 10, 10); 		scrollView.addView(textView); 		textView.setText(Data.DETAILS[getCheckedIndex()]); 		return scrollView;	}		//生成DetailFragment实例,并且保存index	public static DetailFragment newInstance(int index) {		DetailFragment detailFragment = new DetailFragment();		Bundle bundle = new Bundle(); 		bundle.putInt("index", index); 		detailFragment.setArguments(bundle);		return detailFragment;	}	//取出index	public int getCheckedIndex() {		int index =getArguments().getInt("index", 0);		return  index;	}}

package cc.testsimplefragment2;import android.app.Activity;import android.content.res.Configuration;import android.os.Bundle;/** * 在此Activity中我们将一个Fragment嵌入到 * 该Activity中进行显示 */public class DetailActivity extends Activity {	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		//横屏的处理		if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {			finish();			return;		}        		//竖屏的处理		//此处的道理和TitleListFragment中对于横屏的		//处理很相似,只是方式稍有差别.		//1 生成设置好参数的DetailFragment		//2 将此DetailFragment attach到当前的activity		if (savedInstanceState == null) { 			DetailFragment detailFragment = new DetailFragment();			detailFragment.setArguments(getIntent().getExtras()); 			getFragmentManager()			.beginTransaction()			.add(android.R.id.content, detailFragment)			.commit(); 		}	}}

package cc.testsimplefragment2;public final class Data {	//标题    public static final String[] TITLES = { "标题1","标题2", "标题3","标题4"};    //内容    public static final String[] DETAILS = { "内容1","内容2", "内容3","内容4"};}

layout-land/main.xml如下:

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