Android 循环自动滚动广告

知识点：

（1）android.support.v4.view.ViewPager 和 PagerAdapter

（2）android自定义控件——组合控件

1、自定义 "循环自动滚动广告" 控件——MyPosterViewPager.java

package com.chy.widget;import java.util.Timer;import java.util.TimerTask;import android.content.Context;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.util.AttributeSet;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.RelativeLayout;import com.example.myprogressbar.R;/** * 循环自动滚动广告 */public class MyPosterViewPager extends RelativeLayout {private static final int[] TEST_IMAGE_IDS = { R.drawable.image1, R.drawable.image2, R.drawable.image3, R.drawable.image4, R.drawable.image5 };//private static final int[] TEST_IMAGE_IDS = { R.drawable.image5 };// 点点的大小private static final int DOT_IV_SIZE = 10;// 点点的间距private static final int DOT_IV_MARGIN = 5;//滑动间隔private static final int SCROLL_PERIOD_MILLISECONDS = 2000;private ViewPager viewPager = null;// 广告图片数组private ImageView[] posterIvs = null;// 装点点的容器private LinearLayout dotLayout = null;// 装点点的数组private ImageView[] dotIvs = null;//当前显示的页面位置private int currentPosition = 0;// 页面是否改变private boolean isChange = false;//手指是否已经按下private boolean isActionDown = false;// 手指按下的时间，大于1秒的时候进行切换private long actionUpTime = 0;private MyPagerAdapter adapter = null;private Timer timer = null;private final Handler handler = new Handler() {public void handleMessage(Message msg) {viewPager.setCurrentItem(msg.what, true);};};public MyPosterViewPager(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);init(context);}public MyPosterViewPager(Context context, AttributeSet attrs) {super(context, attrs);init(context);}public MyPosterViewPager(Context context) {super(context);init(context);}private void init(Context context) {LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);View parent = inflater.inflate(R.layout.layout_viewpager, this, true);viewPager = (ViewPager) parent.findViewById(R.id.viewpager);dotLayout = (LinearLayout) parent.findViewById(R.id.dot_layout);adapter = new MyPagerAdapter();viewPager.setAdapter(adapter);setPosterImages(context, TEST_IMAGE_IDS);viewPager.setOnTouchListener(new OnTouchListener() {@Overridepublic boolean onTouch(View v, MotionEvent event) {switch (event.getAction()) {case MotionEvent.ACTION_DOWN:isActionDown = true;break;case MotionEvent.ACTION_UP:isActionDown = false;break;}return false;}});viewPager.addOnPageChangeListener(new OnPageChangeListener() {@Overridepublic void onPageSelected(int position) {if(posterIvs.length <= 1) {return;}currentPosition = position;for (int i = 0, resid = 0; i < dotIvs.length; i++) {if (i == (position - 1) || (position == 0 && i == (dotIvs.length - 1))) {resid = R.drawable.shape_dot_focus;} else {resid = R.drawable.shape_dot_unfocus;}dotIvs[i].setBackgroundResource(resid);}if (currentPosition == 0) {currentPosition = posterIvs.length - 2;isChange = true;} else if (currentPosition == posterIvs.length - 1) {currentPosition = 1;isChange = true;}}@Overridepublic void onPageScrolled(int arg0, float arg1, int arg2) {}@Overridepublic void onPageScrollStateChanged(int state) {// SCROLL_STATE_IDLE: pager处于空闲状态// SCROLL_STATE_DRAGGING： pager处于正在拖拽中// SCROLL_STATE_SETTLING： pager正在自动沉降，相当于松手后，pager恢复到一个完整pager的过程if (isChange && state == ViewPager.SCROLL_STATE_IDLE) {viewPager.setCurrentItem(currentPosition, false);}}});timer = new Timer();timer.scheduleAtFixedRate(new TimerTask() {@Overridepublic void run() {if (isActionDown || viewPager == null || posterIvs == null || posterIvs.length <= 1) {return;}if(actionUpTime != 0) {if(System.currentTimeMillis() - actionUpTime > SCROLL_PERIOD_MILLISECONDS) {actionUpTime = 0;} else {return;}}int count = posterIvs.length;int nextItem = (viewPager.getCurrentItem() + 1) % count;//if (nextItem == 0) {//nextItem = count - 2;//} else if (nextItem == (count - 1)) {//nextItem = 1;//}handler.sendEmptyMessage(nextItem);}}, 1000, SCROLL_PERIOD_MILLISECONDS);}/** * 设置广告图片 */public void setPosterImages(Context context, int[] imageIds) {if (imageIds == null || imageIds.length == 0) {return;}dotLayout.removeAllViews();if(imageIds.length == 1) {//如果只有一张图则不允许滑动posterIvs = new ImageView[1];posterIvs[0] = new ImageView(context);posterIvs[0].setBackgroundResource(imageIds[0]);} else {//如果有多张图,则运行循环滚动,并在图片下方显示指示点posterIvs = new ImageView[imageIds.length + 2];dotIvs = new ImageView[imageIds.length];LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(DOT_IV_SIZE, DOT_IV_SIZE);params.setMargins(DOT_IV_MARGIN, DOT_IV_MARGIN, DOT_IV_MARGIN, DOT_IV_MARGIN);for (int i = 0, resid = 0, dotIndex = 0; i < posterIvs.length; i++) {posterIvs[i] = new ImageView(context);if (i == 0) {posterIvs[i].setBackgroundResource(imageIds[imageIds.length - 1]);} else if (i == (posterIvs.length - 1)) {posterIvs[i].setBackgroundResource(imageIds[0]);} else {dotIndex = i - 1;posterIvs[i].setBackgroundResource(imageIds[dotIndex]);dotIvs[dotIndex] = new ImageView(context);if (dotIndex == 0) {resid = R.drawable.shape_dot_focus;} else {resid = R.drawable.shape_dot_unfocus;}dotIvs[dotIndex].setBackgroundResource(resid);dotLayout.addView(dotIvs[dotIndex], params);}}}adapter.notifyDataSetChanged();}class MyPagerAdapter extends PagerAdapter {@Overridepublic int getCount() {if (posterIvs == null || posterIvs.length == 0) {return 0;}return posterIvs.length;}@Overridepublic boolean isViewFromObject(View arg0, Object arg1) {return arg0 == arg1;}@Overridepublic Object instantiateItem(ViewGroup container, int position) {ImageView iv = posterIvs[position];((ViewPager) container).addView(iv);return iv;}@Overridepublic void destroyItem(ViewGroup container, int position, Object object) {((ViewPager) container).removeView(posterIvs[position]);}}}

2、自定义控件布局文件——layout_viewpager.xml

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent" >    <android.support.v4.view.ViewPager        android:id="@+id/viewpager"        android:layout_width="match_parent"        android:layout_height="match_parent" />    <LinearLayout        android:id="@+id/dot_layout"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentBottom="true"        android:layout_centerHorizontal="true"        android:orientation="horizontal" /></RelativeLayout>

3、xml图片资源

（1）shape_dot_focus.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    android:shape="oval" >    <solid android:color="#11C2EE" /></shape>

（2）shape_dot_unfocus.xml

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"    android:shape="oval" >    <solid android:color="#11EE11" /></shape>

4、负责显示广告的Activity——MyViewPagerActivity.java

public class MyViewPagerActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_viewpager);}}

5、测试Activity的布局文件——activity_viewpager.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >    <com.chy.widget.MyPosterViewPager        android:layout_width="match_parent"        android:layout_height="300dp" /></LinearLayout>

6、运行效果图（献上女神——张碧晨的靓照）

7、说明

（1）当仅有1张图片的情况

图片不允许滑动，也不会自动滑动，图片底部无指示点

（2）当图片大于1张的情况

图片会自动循环滑动，支持手势滑动且当手指按住的时候不会自动滑动，图片下方显示和图片个数相当的指示点且对应当前图片的指示点为特异的颜色。