xml 架构资源管理器 xml源没有引用架构

一般viewpage在xml引用如下：

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="
     android:orientation="vertical"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     >
 <android.support.v4.view.ViewPager  
         android:id="@+id/guidePages"  
         android:layout_width="fill_parent"  
         android:layout_height="wrap_content"/>  </LinearLayout>

这样做是没错的，可是运行时找不到android.support.v4.view.ViewPager，已经导入了库文件android-support-v4.jar，

 

 

原因：未添加源文件，做法如下：

新建libs文件夹，将android-support-v4.jar放入到该文件夹下，右键该文件夹，选择Build Path->Use as Source Folder，这样问题就迎刃而解了。

 

 

原因分析：xml文件引用的是源文件。

 

附上代码：

 

main类：

import java.util.ArrayList;
import android.app.Activity;
 import android.os.Bundle;
 import android.support.v4.view.ViewPager;
 import android.view.LayoutInflater;
 import android.view.View;public class ViewPageTest2 extends Activity {
     /** Called when the activity is first created. */
     
     private ViewPager viewPager = null;
     private ArrayList<View> listView = null;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
         initViewPager();
     }
     private void initViewPager() {  
         viewPager = (ViewPager) findViewById(R.id.guidePages);  
         listView = new ArrayList<View>();  
         LayoutInflater inflater = getLayoutInflater();  
         listView.add(inflater.inflate(R.layout.one, null));  
         listView.add(inflater.inflate(R.layout.two, null));  
         listView.add(inflater.inflate(R.layout.three, null));  
         viewPager.setAdapter(new MyPagerAdapter(listView));  
         viewPager.setOnPageChangeListener(new MyPagerChangeListener());  
           
     }  }

 

 

MyPagerAdapter类：

 

import java.util.List;
import android.os.Parcelable;
 import android.support.v4.view.PagerAdapter;
 import android.support.v4.view.ViewPager;
 import android.view.View;public class MyPagerAdapter extends PagerAdapter {  
     
     private List<View> list;  
       
     public MyPagerAdapter(List<View> list) {  
         this.list = list;  
     }  
       
     @Override  
     public void destroyItem(View view, int index, Object arg2) {  
         // TODO Auto-generated method stub  
         ((ViewPager)view).removeView(list.get(index));  
     }      @Override  
     public void finishUpdate(View arg0) {  
         // TODO Auto-generated method stub  
           
     }      @Override  
     public int getCount() {  
         // TODO Auto-generated method stub  
         return list.size();  
     }      @Override  
     public Object instantiateItem(View view, int index) {  
         ((ViewPager)view).addView(list.get(index), 0);  
         return list.get(index);  
     }      @Override  
     public boolean isViewFromObject(View view, Object object) {  
         // TODO Auto-generated method stub  
         return view == (object);  
     }      @Override  
     public void restoreState(Parcelable arg0, ClassLoader arg1) {  
         // TODO Auto-generated method stub  
           
     }      @Override  
     public Parcelable saveState() {  
         // TODO Auto-generated method stub  
         return null;  
     }      @Override  
     public void startUpdate(View arg0) {  
         // TODO Auto-generated method stub  
           
     }  
       
 }   
MyPagerChangeListener类：
import android.support.v4.view.ViewPager.OnPageChangeListener;
public class MyPagerChangeListener implements OnPageChangeListener
 {    @Override
     public void onPageScrollStateChanged(int arg0)
     {
         // TODO Auto-generated method stub
         
     }    @Override
     public void onPageScrolled(int arg0, float arg1, int arg2)
     {
         // TODO Auto-generated method stub
         
     }    @Override
     public void onPageSelected(int arg0)
     {
         // TODO Auto-generated method stub
         
     }}