Fragment(碎片)的使用(左标题右内容实现)

2019独角兽企业重金招聘Python工程师标准>>>

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fragment
			DetailFragment 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FragmentManager
				FragmentTransaction 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 {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
	}

	@Override
	public 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：

转载于:https://my.oschina.net/u/2552902/blog/543992