Android ViewPager控件实现图片轮播

图片轮播在很多app中需要使用到，下面源码是通过Android ViewPgaer控件实现图片轮播。

源码下载：http://download.csdn.net/detail/zouchao911/8308427

效果图：



1、MainActivity.java文件代码：

[java] view
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package com.example.picturecarousel;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.Executors;

import java.util.concurrent.ScheduledExecutorService;

import java.util.concurrent.TimeUnit;

import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.app.Activity;

import android.support.v4.view.PagerAdapter;

import android.support.v4.view.ViewPager;

import android.support.v4.view.ViewPager.OnPageChangeListener;

import android.view.Menu;

import android.view.MotionEvent;

import android.view.View;

import android.view.View.OnTouchListener;

import android.view.ViewGroup;

import android.widget.ImageView;

import android.widget.ImageView.ScaleType;

import android.widget.LinearLayout;

import android.widget.ViewFlipper;

public class MainActivity extends Activity {

private ViewPager view_pager;

private LinearLayout ll_dotGroup;

private int imgResIds[] = new int[] { R.drawable.a, R.drawable.b,

R.drawable.c, R.drawable.d };

private int curIndex = 0;

PicsAdapter picsAdapter;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

view_pager = (ViewPager) findViewById(R.id.view_pager);

ll_dotGroup = (LinearLayout) findViewById(R.id.dotgroup);

picsAdapter = new PicsAdapter(); // 创建适配器

picsAdapter.setData(imgResIds);

view_pager.setAdapter(picsAdapter); // 设置适配器

view_pager.setOnPageChangeListener(new MyPageChangeListener()); //设置页面切换监听器

initPoints(imgResIds.length); // 初始化图片小圆点

startAutoScroll(); // 开启自动播放

}

// 初始化图片轮播的小圆点

private void initPoints(int count) {

for (int i = 0; i < count; i++) {

ImageView iv = new ImageView(this);

LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(

15, 15);

params.setMargins(0, 0, 20, 0);

iv.setLayoutParams(params);

iv.setImageResource(R.drawable.dot1);

ll_dotGroup.addView(iv);

}

((ImageView) ll_dotGroup.getChildAt(curIndex))

.setImageResource(R.drawable.dot2);

}

// 自动播放

private void startAutoScroll() {

ScheduledExecutorService scheduledExecutorService = Executors

.newSingleThreadScheduledExecutor();

// 每隔2秒钟切换一张图片

scheduledExecutorService.scheduleWithFixedDelay(new ViewPagerTask(), 2,

10, TimeUnit.SECONDS);

}

// 切换图片任务

private class ViewPagerTask implements Runnable {

@Override

public void run() {

runOnUiThread(new Runnable() {

@Override

public void run() {

int count = picsAdapter.getCount();

view_pager.setCurrentItem((curIndex + 1) % count);

}

});

}

}

// 定义ViewPager控件页面切换监听器

class MyPageChangeListener implements OnPageChangeListener {

@Override

public void onPageScrolled(int position, float positionOffset,

int positionOffsetPixels) {

}

@Override

public void onPageSelected(int position) {

ImageView imageView1 = (ImageView) ll_dotGroup.getChildAt(position);

ImageView imageView2 = (ImageView) ll_dotGroup.getChildAt(curIndex);

if (imageView1 != null) {

imageView1.setImageResource(R.drawable.dot2);

}

if (imageView2 != null) {

imageView2.setImageResource(R.drawable.dot1);

}

curIndex = position;

}

boolean b = false;

@Override

public void onPageScrollStateChanged(int state) {

//这段代码可不加，主要功能是实现切换到末尾后返回到第一张

switch (state) {

case 1:// 手势滑动

b = false;

break;

case 2:// 界面切换中

b = true;

break;

case 0:// 滑动结束，即切换完毕或者加载完毕

// 当前为最后一张，此时从右向左滑，则切换到第一张

if (view_pager.getCurrentItem() == view_pager.getAdapter()

.getCount() - 1 && !b) {

view_pager.setCurrentItem(0);

}

// 当前为第一张，此时从左向右滑，则切换到最后一张

else if (view_pager.getCurrentItem() == 0 && !b) {

view_pager.setCurrentItem(view_pager.getAdapter()

.getCount() - 1);

}

break;

default:

break;

}

}

}

// 定义ViewPager控件适配器

class PicsAdapter extends PagerAdapter {

private List<ImageView> views = new ArrayList<ImageView>();

@Override

public int getCount() {

if (views == null) {

return 0;

}

return views.size();

}

public void setData(int[] imgResIds) {

for (int i = 0; i < imgResIds.length; i++) {

ImageView iv = new ImageView(MainActivity.this);

ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(

ViewGroup.LayoutParams.MATCH_PARENT,

ViewGroup.LayoutParams.MATCH_PARENT);

iv.setLayoutParams(params);

iv.setScaleType(ScaleType.FIT_XY);

iv.setImageResource(imgResIds[i]);

views.add(iv);

}

}

public Object getItem(int position) {

if (position < getCount())

return views.get(position);

return null;

}

@Override

public boolean isViewFromObject(View arg0, Object arg1) {

return arg0 == arg1;

}

@Override

public void destroyItem(View container, int position, Object object) {

if (position < views.size())

((ViewPager) container).removeView(views.get(position));

}

@Override

public int getItemPosition(Object object) {

return views.indexOf(object);

}

@Override

public Object instantiateItem(View container, int position) {

if (position < views.size()) {

final ImageView imageView = views.get(position);

((ViewPager) container).addView(imageView);

return views.get(position);

}

return null;

}

}

}

2、主布局文件activity_main.xml

[html] view
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<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context=".MainActivity" >

<RelativeLayout

android:layout_width="match_parent"

android:layout_height="150dp"

android:layout_marginBottom="5dp"

android:orientation="vertical" >

<android.support.v4.view.ViewPager

android:id="@+id/view_pager"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:layout_gravity="center" >

</android.support.v4.view.ViewPager>

<LinearLayout

android:id="@+id/dotgroup"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_alignParentBottom="true"

android:gravity="center"

android:layout_marginBottom="15dp"

android:orientation="horizontal" >

</LinearLayout>

</RelativeLayout>

</RelativeLayout>