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1 package com.meityitian.app.views;
  2 
  3 import android.content.Context;
  4 import android.support.v4.view.ViewPager;
  5 import android.util.AttributeSet;
  6 import android.util.Log;
  7 
  8 import com.meityitian.app.utils.Debug;
  9 
 10 /**
 11  * 重写，添加了判定滑动方向的方法
 12  * @author zxy
 13  *
 14  */
 15 public class meityitianViewPager extends ViewPager {
 16     private boolean left = false;
 17     private boolean right = false;
 18     private boolean isScrolling = false;
 19     private int lastValue = -1;
 20     private ChangeViewCallback changeViewCallback = null;
 21 
 22     public meityitianViewPager(Context context, AttributeSet attrs) {
 23         super(context, attrs);
 24         init();
 25     }
 26 
 27     public meityitianViewPager(Context context) {
 28         super(context);
 29         init();
 30     }
 31 
 32     /**
 33      * init method .
 34 */
 35     private void init() {
 36         setOnPageChangeListener(listener);
 37     }
 38 
 39     /**
 40      * listener ,to get move direction .
 41 */
 42     public  OnPageChangeListener listener = new OnPageChangeListener() {
 43         @Override
 44         public void onPageScrollStateChanged(int arg0) {
 45             if (arg0 == 1) {
 46                 isScrolling = true;
 47             } else {
 48                 isScrolling = false;
 49             }
 50 
 51             Debug.infoByTag("meityitianViewPager",
 52                     "meityitianViewPager  onPageScrollStateChanged : arg0:"
 53                             + arg0);
 54             if (arg0 == 2) {
 55                 Debug.infoByTag("meityitianViewPager",
 56                         "meityitianViewPager  onPageScrollStateChanged  direction left ? "
 57                                 + left);
 58                 Debug.infoByTag("meityitianViewPager",
 59                         "meityitianViewPager  onPageScrollStateChanged  direction right ? "
 60                                 + right);
 61                 //notify ....
 62                 if(changeViewCallback!=null){
 63                     changeViewCallback.changeView(left, right);
 64                 }
 65                 right = left = false;
 66             }
 67 
 68         }
 69 
 70         @Override
 71         public void onPageScrolled(int arg0, float arg1, int arg2) {
 72             if (isScrolling) {
 73                 if (lastValue > arg2) {
 74                     // 递减，向右侧滑动
 75                     right = true;
 76                     left = false;
 77                 } else if (lastValue < arg2) {
 78                     // 递减，向右侧滑动
 79                     right = false;
 80                     left = true;
 81                 } else if (lastValue == arg2) {
 82                     right = left = false;
 83                 }
 84             }
 85             Log.i("meityitianViewPager",
 86                     "meityitianViewPager onPageScrolled  last :arg2  ,"
 87                             + lastValue + ":" + arg2);
 88             lastValue = arg2;
 89         }
 90 
 91         @Override
 92         public void onPageSelected(int arg0) {
 93             if(changeViewCallback!=null){
 94                 changeViewCallback.getCurrentPageIndex(arg0);
 95             }
 96         }
 97     };
 98     
 99     /**
100      * 得到是否向右侧滑动
101      * @return true 为右滑动
102 */
103     public boolean getMoveRight(){
104         return right;
105     }
106     
107     /**
108      * 得到是否向左侧滑动
109      * @return true 为左做滑动
110 */
111     public boolean getMoveLeft(){
112         return left;
113     }
114     
115     /**
116      *  滑动状态改变回调
117      * @author zxy
118      *
119 */
120     public interface ChangeViewCallback{
121         /**
122          * 切换视图 ？决定于left和right 。
123          * @param left
124          * @param right
125 */
126         public  void changeView(boolean left,boolean right);
127         public  void  getCurrentPageIndex(int index);
128     }
129     
130     /**
131      * set ...
132      * @param callback
133 */
134     public void  setChangeViewCallback(ChangeViewCallback callback){
135         changeViewCallback = callback;
136     }
137 }