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() {
@Override
public 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() {
@Override
public 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;
}
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public 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() {
@Override
public 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 {
@Override
public int getCount() {
if (posterIvs == null || posterIvs.length == 0) {
return 0;
}
return posterIvs.length;
}
@Override
public boolean isViewFromObject(View arg0, Object arg1) {
return arg0 == arg1;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
ImageView iv = posterIvs[position];
((ViewPager) container).addView(iv);
return iv;
}
@Override
public 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 {
@Override
protected 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。