Android 利用ViewPager實現圖片可以左右循環滑動效果附代碼下載

首先給大家展示靓照，對效果圖感興趣的朋友可以繼續往下閱讀哦。

ViewPager這個小demo實現的是可以左右循環滑動圖片，下面帶索引，滑到最後一頁在往右滑動就要第一頁，第一頁往左滑動就到最後一頁，上面是效果圖，用美女圖片是我一貫的作風，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這個jar包。自己不要忘記加

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; 
 /** 
 * 裝點點的ImageView數組 
 */ 
 private ImageView[] tips; 
 /** 
 * 裝ImageView數組 
 */ 
 private ImageView[] mImageViews; 
 /** 
 * 圖片資源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); 
 //載入圖片資源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}; 
 //將點點加入到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); 
 } 
 //將圖片裝載到數組中 
 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]); 
 } 
 //設置Adapter 
 viewPager.setAdapter(new MyAdapter()); 
 //設置監聽，主要是設置點點的背景 
 viewPager.setOnPageChangeListener(this); 
 //設置ViewPager的默認項, 設置為長度的100倍，這樣子開始就能往左滑動 
 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]); 
 } 
 /** 
 * 載入圖片進去，用當前的position 除以 圖片數組長度取余數是關鍵 
 */ 
 @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); 
 } 
 /** 
 * 設置選中的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); 
 } 
 } 
 } 
} 

喜歡的朋友直接下載代碼哦。代碼下載

上面的代碼中，當只有3張圖片或者2張圖片的時候，滑動存在BUG問題的修改如下

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)增加異常撲捉
[java] view plaincopy在CODE上查看代碼片派生到我的代碼片
@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]; 
 } 

以上代碼給大家展示了Android 利用ViewPager實現圖片可以左右循環滑動效果，希望大家喜歡。