Android利用ViewPager实现滑动广告板实例源码

•android-support-v4.jar,这是谷歌官方给我们提供的一个兼容低版本android设备的软件包，里面包囊了只有在android3.0以上可以使用的api。而viewpager就是其中之一,利用它我们可以做很多事情，从最简单的导航，到页面切换菜单等等。

•viewpager的功能就是可以使视图滑动，就像lanucher左右滑动那样。
•本demo向大家演示viewpager的使用，并在用户未滑动view时，每隔5s钟自动切换到下一个view(循环切换)，而当用户有touch到view时取消5s自动切换功能。并有指示器指示当前处于哪一个view。

下面是运行的截图：
 
这个是非常常见的应用
下面给出实现的代码：
1.源文件

package com.eyeandroid.viewpager;
import java.util.arraylist;
import java.util.list;
import java.util.concurrent.atomic.atomicinteger;
import android.annotation.suppresslint;
import android.app.activity;
import android.os.bundle;
import android.os.handler;
import android.os.message;
import android.os.parcelable;
import android.support.v4.view.pageradapter;
import android.support.v4.view.viewpager;
import android.support.v4.view.viewpager.onpagechangelistener;
import android.view.motionevent;
import android.view.view;
import android.view.view.ontouchlistener;
import android.view.viewgroup;
import android.view.viewgroup.layoutparams;
import android.widget.imageview;
@suppresslint("handlerleak")
public class mainactivity extends activity {
private imageview[] imageviews = null;
private imageview imageview = null;
private viewpager advpager = null;
private atomicinteger what = new atomicinteger(0);
private boolean iscontinue = true;
@override
public void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.main);
initviewpager();
}

private void initviewpager() {
advpager = (viewpager) findviewbyid(r.id.adv_pager);
viewgroup group = (viewgroup) findviewbyid(r.id.viewgroup);
// 这里存放的是四张广告背景
list<view> advpics = new arraylist<view>();
imageview img1 = new imageview(this);
img1.setbackgroundresource(r.drawable.advertising_default_1);
advpics.add(img1);
imageview img2 = new imageview(this);
img2.setbackgroundresource(r.drawable.advertising_default_2);
advpics.add(img2);
imageview img3 = new imageview(this);
img3.setbackgroundresource(r.drawable.advertising_default_3);
advpics.add(img3);
imageview img4 = new imageview(this);
img4.setbackgroundresource(r.drawable.advertising_default);
advpics.add(img4);

// 对imageviews进行填充
imageviews = new imageview[advpics.size()];
//小图标
for (int i = 0; i < advpics.size(); i++) {
imageview = new imageview(this);
imageview.setlayoutparams(new layoutparams(20, 20));
imageview.setpadding(5, 5, 5, 5);
imageviews[i] = imageview;
if (i == 0) {
imageviews[i]
.setbackgroundresource(r.drawable.banner_dian_focus);
} else {
imageviews[i]
.setbackgroundresource(r.drawable.banner_dian_blur);
}
group.addview(imageviews[i]);
}
advpager.setadapter(new advadapter(advpics));
advpager.setonpagechangelistener(new guidepagechangelistener());
advpager.setontouchlistener(new ontouchlistener() {

@override
public boolean ontouch(view v, motionevent event) {
switch (event.getaction()) {
case motionevent.action_down:
case motionevent.action_move:
iscontinue = false;
break;
case motionevent.action_up:
iscontinue = true;
break;
default:
iscontinue = true;
break;
}
return false;
}
});
new thread(new runnable() {
@override
public void run() {
while (true) {
if (iscontinue) {
viewhandler.sendemptymessage(what.get());
whatoption();
}
}
}
}).start();
}

private void whatoption() {
what.incrementandget();
if (what.get() > imageviews.length - 1) {
what.getandadd(-4);
}
try {
thread.sleep(5000);
} catch (interruptedexception e) {

}
}
private final handler viewhandler = new handler() {
@override
public void handlemessage(message msg) {
advpager.setcurrentitem(msg.what);
super.handlemessage(msg);
}
};
private final class guidepagechangelistener implements onpagechangelistener {
@override
public void onpagescrollstatechanged(int arg0) {
}
@override
public void onpagescrolled(int arg0, float arg1, int arg2) {
}
@override
public void onpageselected(int arg0) {
what.getandset(arg0);
for (int i = 0; i < imageviews.length; i++) {
imageviews[arg0]
.setbackgroundresource(r.drawable.banner_dian_focus);
if (arg0 != i) {
imageviews[i]
.setbackgroundresource(r.drawable.banner_dian_blur);
}
}
}
}
private final class advadapter extends pageradapter {
private list<view> views = null;
public advadapter(list<view> views) {
this.views = views;
}
@override
public void destroyitem(view arg0, int arg1, object arg2) {
((viewpager) arg0).removeview(views.get(arg1));
}
@override
public void finishupdate(view arg0) {
}
@override
public int getcount() {
return views.size();
}
@override
public object instantiateitem(view arg0, int arg1) {
((viewpager) arg0).addview(views.get(arg1), 0);
return views.get(arg1);
}
@override
public boolean isviewfromobject(view arg0, object arg1) {
return arg0 == arg1;
}
@override
public void restorestate(parcelable arg0, classloader arg1) {
}
@override
public parcelable savestate() {
return null;
}
@override
public void startupdate(view arg0) {
}
}
}

2.布局文件
这个文件在屏幕上的图片显示具有至关重要的作用

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<relativelayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
<!-- viewpager是一个控件 -->
<android.support.v4.view.viewpager
android:id="@+id/adv_pager"
android:layout_width="fill_parent"
android:layout_height="160dp" >
</android.support.v4.view.viewpager>
<linearlayout
android:id="@+id/viewgroup"
android:layout_below="@id/adv_pager"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_margintop="-25px"
android:gravity="right"
android:orientation="horizontal" >
</linearlayout>
</relativelayout>
</linearlayout>