1 import java.util.ArrayList;
  2 import java.util.concurrent.Executors;
  3 import java.util.concurrent.ScheduledExecutorService;
  4 import java.util.concurrent.TimeUnit;
  5 
  6 import android.app.Activity;
  7 import android.os.Bundle;
  8 import android.os.Handler;
  9 import android.os.Message;
 
 10 import android.support.v4.view.PagerAdapter;
 11 import android.support.v4.view.ViewPager;
 12 import android.support.v4.view.ViewPager.OnPageChangeListener;
 13 import android.view.View;
 14 import android.view.ViewGroup;
 15 import android.widget.ImageView;
 16 import android.widget.TextView;
 17
 
 
 18 public class MainActivity extends Activity {
 19 
 20     private int imageIds[];
 21     private String[] titles;
 22     private ArrayList<ImageView> images;
 23     private ArrayList<View> dots;
 24     private TextView title;
 25     private ViewPager mViewPager;
 26     private
 
 ViewPagerAdapter adapter;
 27     
 28     private int oldPosition = 0;//記錄上一次點的位置
 29     private int currentItem; //當前頁面
 30     private ScheduledExecutorService scheduledExecutorService;
 31 
 32     @Override
 33     public void onCreate(Bundle savedInstanceState) {
 34         super.onCreate(savedInstanceState);
 35         setContentView(R.layout.activity_main);
 36         
 37         //圖片ID
 38         imageIds = new int[]{
 39             R.drawable.a,    
 40             R.drawable.b,    
 41             R.drawable.c,    
 42             R.drawable.d,    
 43             R.drawable.e    
 44         };
 45         
 46         //圖片標題
 47         titles = new String[]{
 48             "鞏俐不低俗，我就不能低俗",    
 49             "撲樹又回來啦！再唱經典老歌引萬人大合唱",    
 50             "揭祕北京電影如何升級",    
 51             "樂視網TV版大派送",    
 52             "熱血屌絲的反殺"
 53         };
 54         
 55         //顯示的圖片
 56         images = new ArrayList<ImageView>();
 57         for(int i =0; i < imageIds.length; i++){
 58             ImageView imageView = new ImageView(this);
 59             imageView.setBackgroundResource(imageIds[i]);
 60             
 61             images.add(imageView);
 62         }
 63         
 64         //顯示的點
 65         dots = new ArrayList<View>();
 66         dots.add(findViewById(R.id.dot_0));
 67         dots.add(findViewById(R.id.dot_1));
 68         dots.add(findViewById(R.id.dot_2));
 69         dots.add(findViewById(R.id.dot_3));
 70         dots.add(findViewById(R.id.dot_4));
 71         
 72         title = (TextView) findViewById(R.id.title);
 73         title.setText(titles[0]);
 74         
 75         mViewPager = (ViewPager) findViewById(R.id.vp);
 76         
 77         adapter = new ViewPagerAdapter(); 
 78         mViewPager.setAdapter(adapter);
 79         
 80         mViewPager.setOnPageChangeListener(new OnPageChangeListener() {
 81             
 82 
 83 
 84             @Override
 85             public void onPageSelected(int position) {
 86                 // TODO Auto-generated method stub
 87                 title.setText(titles[position]);
 88                 
 89                 dots.get(oldPosition).setBackgroundResource(R.drawable.dot_normal);
 90                 dots.get(position).setBackgroundResource(R.drawable.dot_focused);
 91                 
 92                 oldPosition = position;
 93                 currentItem = position;
 94             }
 95             
 96             @Override
 97             public void onPageScrolled(int arg0, float arg1, int arg2) {
 98                 // TODO Auto-generated method stub
 99                 
100             }
101             
102             @Override
103             public void onPageScrollStateChanged(int arg0) {
104                 // TODO Auto-generated method stub
105                 
106             }
107         });
108         
109     }
110     
111     private class ViewPagerAdapter extends PagerAdapter {
112 
113         @Override
114         public int getCount() {
115             // TODO Auto-generated method stub
116             return images.size();
117         }
118 
119         //是否是同一張圖片
120         @Override
121         public boolean isViewFromObject(View arg0, Object arg1) {
122             // TODO Auto-generated method stub
123             return arg0 == arg1;
124         }
125 
126         @Override
127         public void destroyItem(ViewGroup view, int position, Object object) {
128             // TODO Auto-generated method stub
129 //            super.destroyItem(container, position, object);
130 //            view.removeViewAt(position);
131             view.removeView(images.get(position));
132             
133         }
134 
135         @Override
136         public Object instantiateItem(ViewGroup view, int position) {
137             // TODO Auto-generated method stub
138             view.addView(images.get(position));
139             
140             return images.get(position);
141         }
142     }
143 
144     @Override
145     protected void onStart() {
146         // TODO Auto-generated method stub
147         super.onStart();
148         
149         scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();
150         
151         //每隔2秒鐘切換一張圖片
152         scheduledExecutorService.scheduleWithFixedDelay(new ViewPagerTask(), 2, 2, TimeUnit.SECONDS);
153     }
154     
155     //切換圖片
156     private class ViewPagerTask implements Runnable {
157 
158         @Override
159         public void run() {
160             // TODO Auto-generated method stub
161             currentItem = (currentItem +1) % imageIds.length;
162             //更新介面
163 //            handler.sendEmptyMessage(0);
164             handler.obtainMessage().sendToTarget();
165         }
166         
167     }
168     
169     private Handler handler = new Handler(){
170 
171         @Override
172         public void handleMessage(Message msg) {
173             // TODO Auto-generated method stub
174             //設定當前頁面
175             mViewPager.setCurrentItem(currentItem);
176         }
177         
178     };
179 
180     @Override
181     protected void onStop() {
182         // TODO Auto-generated method stub
183         super.onStop();
184     }
185     
186     
187 
188 }