android轮播图示例

首先轮播图使用ViewPager控件来播放，如果有不懂ViewPager可以先去了解一下,可以看看我之前写的http://blog.csdn.net/ksj_j/article/details/53588080

首先说一下我们要实现的功能有图片可以滑动轮播，可以自动轮播，还有标记显示图片处于第几张图片的圆点

效果图如下

activity_main.xml

<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="com.example.viewpager.MainActivity" >    <android.support.v4.view.ViewPager android:id="@+id/vp" android:layout_height="match_parent" android:layout_width="match_parent"></android.support.v4.view.ViewPager> <RelativeLayout        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentBottom="true"        android:layout_centerHorizontal="true"        android:layout_marginBottom="20dp" >    <LinearLayout        android:id="@+id/ll"        android:orientation="horizontal"        android:layout_height="wrap_content"        android:layout_width="wrap_content">    </LinearLayout>    <ImageView             android:id="@+id/iv"            android:src="@drawable/circle_bg"            android:layout_height="wrap_content"            android:layout_width="wrap_content"/>    </RelativeLayout>    </RelativeLayout>

MainActivity.java

package com.example.viewpager;import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.app.ActivityManager.RunningAppProcessInfo;import android.os.Bundle;import android.os.Handler;import android.os.Message;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.ViewTreeObserver.OnGlobalLayoutListener;import android.widget.ImageView;import android.widget.ImageView.ScaleType;import android.widget.LinearLayout;import android.widget.RelativeLayout;public class MainActivity extends Activity {private ViewPager vp;private LinearLayout ll;private ImageView iv;        //每次圆点移动的位移       private int move;        //图片资源       private int[] image =new int[]{R.drawable.iv1,R.drawable.iv2,R.drawable.iv3,R.drawable.iv4,R.drawable.iv5};private List<ImageView> imagelist;        判断是否需要自动播放       private boolean running = true;        //实现自动播放       private Handler handler = new Handler(){//每隔5秒自动实现vp的position加1public void handleMessage(Message msg) {vp.setCurrentItem(vp.getCurrentItem()+1);System.out.println(vp.getCurrentItem());if(running){handler.sendEmptyMessageDelayed(0, 3000);}};};@Overrideprotected void onDestroy() {running = false;        super.onDestroy();};@SuppressWarnings("deprecation")@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initView();//handler.sendEmptyMessage(1);for(int i = 0; i < image.length; i ++){ImageView imageView = new ImageView(this);imageView.setImageResource(image[i]);imageView.setScaleType(ScaleType.FIT_XY);imagelist.add(imageView);//根据图片的个数去放置相应数量的圆点3ImageView imageView2 = new ImageView(this);imageView2.setImageResource(R.drawable.circle);                        //因为没有直接改变margin的方法，所以这里使用的LayoutParams来改变leftMargin                       LinearLayout.LayoutParams  layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);if(i > 0){layoutParams.leftMargin = 20;}imageView2.setLayoutParams(layoutParams);ll.addView(imageView2);}//布局加载完成节后运行iv.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {@Overridepublic void onGlobalLayout() {// TODO Auto-generated method stub//内部子空间的距离获取move = ll.getChildAt(1).getLeft()-ll.getChildAt(0).getLeft();}});//添加监听时间vp.setOnPageChangeListener(new OnPageChangeListener() {@Overridepublic void onPageSelected(int arg0) {// TODO Auto-generated method stub}//滑动界面触发，这里控制标记点的改变就可以了//position第几幅图，offset滑动百分比@Overridepublic void onPageScrolled(int position, float offset, int arg2) {// TODO Auto-generated method stubSystem.out.println(position);RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams)iv.getLayoutParams();if((position+1)%image.length != 0)layoutParams.leftMargin = (int)((position%image.length)*move+offset*move);iv.setLayoutParams(layoutParams);}@Overridepublic void onPageScrollStateChanged(int arg0) {// TODO Auto-generated method stub}});//添加适配器//vp.setPageTransformer(true, arg1);vp.setAdapter(new PagerAdapter() {@Overridepublic Object instantiateItem(ViewGroup container, int position) {// TODO Auto-generated method stubcontainer.addView(imagelist.get((position+image.length)%(image.length)));//返回滑动到的图片return imagelist.get((position+image.length)%(image.length));}@Overridepublic void destroyItem(ViewGroup container, int position, Object object) {// TODO Auto-generated method stub                                //移除一张前图片                               container.removeView(imagelist.get((position+image.length)%(image.length)));}@Overridepublic boolean isViewFromObject(View arg0, Object arg1) {// TODO Auto-generated method stubreturn arg0 == arg1;}//使得ViewPager可以无限移动，设置边界为Integer.MAX_VALUE@Overridepublic int getCount() {// TODO Auto-generated method stubreturn Integer.MAX_VALUE;}});//插入切换样式，这个随便一个地方拷贝一份即可，可以到官方拷贝vp.setPageTransformer(true, new DepthPageTransformer());        handler.sendEmptyMessageDelayed(0, 3000);}private void initView() {// TODO Auto-generated method stubll = (LinearLayout)findViewById(R.id.ll);vp = (ViewPager)findViewById(R.id.vp);iv = (ImageView)findViewById(R.id.iv);imagelist = new ArrayList<>();}}

圆点设计：圆点表示第几幅图

circle.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"     android:shape="oval">    <size android:width="10dp"        android:height="10dp"/>    <solid         android:color="#c0c0c0"/></shape>

circle_bg.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    android:shape="oval" >    <size         android:width="10dp"        android:height="10dp"/>        <solid        android:color="#ff0000"/></shape>

改变切换图样式代码

DepthPageTransformer.java

package com.example.viewpager;import android.annotation.SuppressLint;import android.support.v4.view.ViewPager.PageTransformer;import android.view.View;public class DepthPageTransformer implements PageTransformer {    private static final float MIN_SCALE = 0.75f;    @SuppressLint("NewApi")public void transformPage(View view, float position) {        int pageWidth = view.getWidth();        if (position < -1) { // [-Infinity,-1)            // This page is way off-screen to the left.            view.setAlpha(0);        } else if (position <= 0) { // [-1,0]            // Use the default slide transition when moving to the left page            view.setAlpha(1);            view.setTranslationX(0);            view.setScaleX(1);            view.setScaleY(1);        } else if (position <= 1) { // (0,1]            // Fade the page out.            view.setAlpha(1 - position);            // Counteract the default slide transition            view.setTranslationX(pageWidth * -position);            // Scale the page down (between MIN_SCALE and 1)            float scaleFactor = MIN_SCALE                    + (1 - MIN_SCALE) * (1 - Math.abs(position));            view.setScaleX(scaleFactor);            view.setScaleY(scaleFactor);        } else { // (1,+Infinity]            // This page is way off-screen to the right.            view.setAlpha(0);        }    }}

总结：首先我使用的是ViewPager实现轮播图，继承PagerAdapter重写方法实现图片的切换，实现接口OnPageChangeListener监听可以来动态改变圆点的位子，接下来实现轮播图自动播放

自动循环： 1.定时器：Timer 2.开子线程：while true循环 3.ClockManger 4.用Handler发送延时信息，实现循环，最简单最方便

这里我使用Handler来实现自动循环