图片轮播小圆点
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android:layout_width="match_parent"
android:layout_height="match_parent">
android:layout_width="match_parent"
android:layout_height="200dp">
android:id="@+id/linear_layout"
android:layout_alignBottom="@+id/view_pager"
android:layout_gravity="center_horizontal"
android:layout_centerHorizontal="true"
android:layout_marginBottom="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
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动态添加小圆点的方法
/**
* 动态添加小圆点
* @param list
*/
private void initDoc(List
//1.需要一个集合记录一下小圆点的imageView控件
images = new ArrayList
//2...linearLayout上面的视图清空一下再去添加
linearLayout.removeAllViews();
for (int i=0;i
if (i==0){
imageView.setImageResource(R.drawable.shape_01);
}else {
imageView.setImageResource(R.drawable.shape_02);
}
//添加到集合去
images.add(imageView);
//添加到线性布局上
//这是布局参数,,刚开始小圆点之间没有距离,所以使用java代码指定宽度高度,并且指定小圆点之间的距离
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
params.setMargins(5,0,5,0);
linearLayout.addView(imageView,params);
}
}
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//3.根据集合的长度动态添加小圆点...linearLayout，集合是指获取的json的集合
initDoc(list);
//2.手动的可以无限滑动
viewPager.setCurrentItem(list.size()*100000);//设置当前展示中间某个足够大的位置
handler.sendEmptyMessageDelayed(0,2000);//发送一个延时的空消息
//viewPage设置监听事件
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
/**
* 当选中某个页面的时候,把当前的小圆点背景变成绿色
* @param position
*/
@Override
public void onPageSelected(int position) {
for (int i=0;i
images.get(i).setImageResource(R.drawable.shape_01);
}else {
images.get(i).setImageResource(R.drawable.shape_02);
}
}
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
}
}
};
asyncTask.execute();
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添加handler
private Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
if (msg.what == 0){
//viewPager显示下一页
viewPager.setCurrentItem(viewPager.getCurrentItem() +1);
//再次发送延时消息
handler.sendEmptyMessageDelayed(0,2000);
}
}
};
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适配器里需要配置
public class MyAdapter extends PagerAdapter {
Context context;
List
Handler handler;
public MyAdapter(Context context, List
this.context = context;
this.list = list;
this.handler = handler;
}
@Override
public int getCount() {
return Integer.MAX_VALUE;
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
/**
* viewPager具有预加载,默认的前后加载一页,,,默认的容器里面最多三页
* @param container
* @param position
* @return
*/
@Override
public Object instantiateItem(ViewGroup container, int position) {
//1.把这个当前展示的视图添加到容器中...container
ImageView imageView = new ImageView(context);
//..........使图片平铺整个imageView控件
imageView.setScaleType(ImageView.ScaleType.FIT_XY);
//imageLoader加载图片到这个imageView控件上
ImageLoader.getInstance().displayImage(list.get(position %list.size()).getImg(),imageView,ImageLoaderUtil.getDefaultOption());
//给imageView设置触摸的监听事件
imageView.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
int action = motionEvent.getAction();//获取手指的动作
switch (action){
case MotionEvent.ACTION_DOWN://按下的动作...应该取消发送消息的操作
handler.removeCallbacksAndMessages(null);
break;
case MotionEvent.ACTION_MOVE://移动的动作
handler.removeCallbacksAndMessages(null);
break;
case MotionEvent.ACTION_CANCEL://取消
//重新发送
handler.sendEmptyMessageDelayed(0,2000);
break;
case MotionEvent.ACTION_UP://抬起的动作
handler.sendEmptyMessageDelayed(0,2000);
break;
}
//返回true表示自己处理触摸事件
return true;
}
});
container.addView(imageView);//添加到容器
//2.把当前展示的视图返回
return imageView;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
//销毁视图
container.removeView((View) object);
}
}