Android 利用ViewPager实现图片可以左右循环滑动效果附代码下载

首先给大家展示靓照，对效果图感兴趣的朋友可以继续往下阅读哦。

viewpager这个小demo实现的是可以左右循环滑动图片，下面带索引，滑到最后一页在往右滑动就要第一页，第一页往左滑动就到最后一页，上面是效果图，用美女图片是我一贯的作风，呵呵

 1.    首先看一些layout下的xml

<framelayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent" 
 android:orientation="vertical" > 
 <android.support.v4.view.viewpager 
 android:id="@+id/viewpager" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" /> 
 <relativelayout 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:orientation="vertical" > 
 <linearlayout 
 android:id="@+id/viewgroup" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:layout_alignparentbottom="true" 
 android:layout_marginbottom="30dp" 
 android:gravity="center_horizontal" 
 android:orientation="horizontal" > 
 </linearlayout> 
 </relativelayout> 
</framelayout> 

使用viewpager首先需要引入android-support-v4.jar这个jar包。自己不要忘记加

package com.example.viewpagerdemo; 
import android.app.activity; 
import android.os.bundle; 
import android.support.v4.view.pageradapter; 
import android.support.v4.view.viewpager; 
import android.support.v4.view.viewpager.onpagechangelistener; 
import android.view.view; 
import android.view.viewgroup; 
import android.view.viewgroup.layoutparams; 
import android.widget.imageview; 
import android.widget.linearlayout; 
public class twoactivity extends activity implements onpagechangelistener{ 
 /** 
 * viewpager 
 */ 
 private viewpager viewpager; 
 /** 
 * 装点点的imageview数组 
 */ 
 private imageview[] tips; 
 /** 
 * 装imageview数组 
 */ 
 private imageview[] mimageviews; 
 /** 
 * 图片资源id 
 */ 
 private int[] imgidarray ; 
 @override 
 protected void oncreate(bundle savedinstancestate) { 
 super.oncreate(savedinstancestate); 
 setcontentview(r.layout.activity_main); 
 viewgroup group = (viewgroup)findviewbyid(r.id.viewgroup); 
 viewpager = (viewpager) findviewbyid(r.id.viewpager); 
 //载入图片资源id 
 imgidarray = new int[]{r.drawable.item01, r.drawable.item02, r.drawable.item03, r.drawable.item04, 
 r.drawable.item05,r.drawable.item06, r.drawable.item07, r.drawable.item08}; 
 //将点点加入到viewgroup中 
 tips = new imageview[imgidarray.length]; 
 for(int i=0; i<tips.length; i++){ 
 imageview imageview = new imageview(this); 
 imageview.setlayoutparams(new layoutparams(10,10)); 
 tips[i] = imageview; 
 if(i == 0){ 
 tips[i].setbackgroundresource(r.drawable.page_indicator_focused); 
 }else{ 
 tips[i].setbackgroundresource(r.drawable.page_indicator_unfocused); 
 } 
 linearlayout.layoutparams layoutparams = new linearlayout.layoutparams(new viewgroup.layoutparams(layoutparams.wrap_content, 
  layoutparams.wrap_content)); 
 layoutparams.leftmargin = 5; 
 layoutparams.rightmargin = 5; 
 group.addview(imageview, layoutparams); 
 } 
 //将图片装载到数组中 
 mimageviews = new imageview[imgidarray.length]; 
 for(int i=0; i<mimageviews.length; i++){ 
 imageview imageview = new imageview(this); 
 mimageviews[i] = imageview; 
 imageview.setbackgroundresource(imgidarray[i]); 
 } 
 //设置adapter 
 viewpager.setadapter(new myadapter()); 
 //设置监听，主要是设置点点的背景 
 viewpager.setonpagechangelistener(this); 
 //设置viewpager的默认项, 设置为长度的100倍，这样子开始就能往左滑动 
 viewpager.setcurrentitem((mimageviews.length) * 100); 
 } 
 /** 
 * 
 * @author xiaanming 
 * 
 */ 
 public class myadapter extends pageradapter{ 
 @override 
 public int getcount() { 
 return integer.max_value; 
 } 
 @override 
 public boolean isviewfromobject(view arg0, object arg1) { 
 return arg0 == arg1; 
 } 
 @override 
 public void destroyitem(view container, int position, object object) { 
 ((viewpager)container).removeview(mimageviews[position % mimageviews.length]); 
 } 
 /** 
 * 载入图片进去，用当前的position 除以 图片数组长度取余数是关键 
 */ 
 @override 
 public object instantiateitem(view container, int position) { 
 ((viewpager)container).addview(mimageviews[position % mimageviews.length], 0); 
 return mimageviews[position % mimageviews.length]; 
 } 
 } 
 @override 
 public void onpagescrollstatechanged(int arg0) { 
 } 
 @override 
 public void onpagescrolled(int arg0, float arg1, int arg2) { 
 } 
 @override 
 public void onpageselected(int arg0) { 
 setimagebackground(arg0 % mimageviews.length); 
 } 
 /** 
 * 设置选中的tip的背景 
 * @param selectitems 
 */ 
 private void setimagebackground(int selectitems){ 
 for(int i=0; i<tips.length; i++){ 
 if(i == selectitems){ 
 tips[i].setbackgroundresource(r.drawable.page_indicator_focused); 
 }else{ 
 tips[i].setbackgroundresource(r.drawable.page_indicator_unfocused); 
 } 
 } 
 } 
} 

喜欢的朋友直接下载代码哦。代码下载

上面的代码中，当只有3张图片或者2张图片的时候，滑动存在bug问题的修改如下

destroyitem(view container, int position, object object)方法中不removeview

 @override 
 public void destroyitem(view container, int position, object object) { 
// ((viewpager)container).removeview(mimageviews[position % mimageviews.length]); 
 } 
instantiateitem(view container, int position)增加异常扑捉
[java] view plaincopy在code上查看代码片派生到我的代码片
@override 
 public object instantiateitem(view container, int position) { 
 try { 
 ((viewpager)container).addview(mimageviews[position % mimageviews.length], 0); 
 }catch(exception e){ 
 //handler something 
 } 
 return mimageviews[position % mimageviews.length]; 
 } 

以上代码给大家展示了android 利用viewpager实现图片可以左右循环滑动效果，希望大家喜欢。