Android 自定义ViewPager 实现轮播图

/**
* Created by Administrator on 2017-10-26.
*/
public class CustomerViewPagerComponent extends RelativeLayout implements
       ViewPager.OnPageChangeListener {
   private final int MAX_COUNT = Integer.MAX_VALUE;
   private final int TIME_INTERVAL = 3000;
   public final int MSG_CODE = 0x986;
   private int[] imgs;
   private ImageView[] imageViews;
   private ViewPager viewPager;
   private LinearLayout linearLayout;
   @SuppressWarnings("unused")
   private List dots;
   private boolean autoPlayFlag;
   private int currentNumber;

   @SuppressWarnings("deprecation")
   public void setImgs(int[] imgs) {
       this.imgs = imgs;
       if (imgs != null) {
           imageViews = new ImageView[imgs.length];
           for (int i = 0; i < imgs.length; i++) {

imageViews[i] = new ImageView(getContext());

//这里使用了Glide第三方的工具，

                Glide.with(getContext()).load(imgs[i])
                       .diskCacheStrategy(DiskCacheStrategy.NONE)//设置glide加载图片不缓存
                       .into(imageViews[i]);
               imageViews[i].setScaleType(ImageView.ScaleType.FIT_XY);
           }
           // 设置适配器
           viewPager.setAdapter(new MyAdapter());
           // 设置ViewPager的默认项, 设置为长度的100倍，这样子开始就能往左滑动
           currentNumber = (imageViews.length) * 100;
           viewPager.setCurrentItem(currentNumber);
           // 设置监听器
           viewPager.setOnPageChangeListener(this);
           // 开始自动播放
           final Message message = handler.obtainMessage(MSG_CODE);
           handler.sendMessageDelayed(message, TIME_INTERVAL);
           // 设置点点
           setDot(currentNumber);
       }
   }

   // 构造
   public CustomerViewPagerComponent(Context context, AttributeSet attrs) {
       super(context, attrs);
       viewPager = new ViewPager(getContext());
       viewPager.setLayoutParams(new RelativeLayout.LayoutParams(
               ViewGroup.LayoutParams.MATCH_PARENT,
               ViewGroup.LayoutParams.MATCH_PARENT));
       addView(viewPager);
       autoPlayFlag = true;

   }

   // 设置ViewPager的适配器
   public class MyAdapter extends PagerAdapter {
       @Override
       public int getCount() {
           return MAX_COUNT;
       }

       @Override
       public boolean isViewFromObject(View view, Object object) {
           return view == object;
       }

       @Override
       public void destroyItem(ViewGroup container, int position, Object object) {
           container.removeView(imageViews[position % imageViews.length]);
       }

       @Override
       public Object instantiateItem(ViewGroup container, int position) {
           container.addView(imageViews[position % imageViews.length], 0);
           return imageViews[position % imageViews.length];
       }
   }

   @SuppressLint("HandlerLeak")
   public Handler handler = new Handler() {
       @Override
       public void handleMessage(Message msg) {
           super.handleMessage(msg);
           if (msg.what == MSG_CODE) {
               if (autoPlayFlag) {
                   showNext();
               }
               Message message = handler.obtainMessage(MSG_CODE);
               handler.sendMessageDelayed(message, TIME_INTERVAL);
           }

       }
   };

   public void showNext() {
       currentNumber++;
       viewPager.setCurrentItem(currentNumber);
       // 设置点点
       setDot(currentNumber);
   }

   public void showPrevious() {
       currentNumber--;
       viewPager.setCurrentItem(currentNumber);
       // 设置点点
       setDot(currentNumber);
   }

   @Override
   public void onPageScrolled(int position, float positionOffset,
           int positionOffsetPixels) {

   }

   @Override
   public void onPageSelected(int position) {
       currentNumber = position;
       // 设置点点
       setDot(currentNumber);
   }

   @Override
   public void onPageScrollStateChanged(int state) {
       switch (state) {
       case ViewPager.SCROLL_STATE_IDLE:
           // 无动作、初始状态
           break;
       case ViewPager.SCROLL_STATE_DRAGGING:
           // 点击、滑屏
           autoPlayFlag = false;
           break;
       case ViewPager.SCROLL_STATE_SETTLING:
           // 释放
           autoPlayFlag = true;
           break;
       }
   }

   // 设置当前选中的点点
   private void setDot(int currentNumber) {
       // remove
       removeView(linearLayout);
       // 设置点点
       linearLayout = new LinearLayout(getContext());
       RelativeLayout.LayoutParams reLayoutParams = new RelativeLayout.LayoutParams(
               ViewGroup.LayoutParams.MATCH_PARENT,
               ViewGroup.LayoutParams.WRAP_CONTENT);
       reLayoutParams.setMargins(0, 0, 0, 30);
       reLayoutParams.addRule(ALIGN_PARENT_BOTTOM);
       linearLayout.setLayoutParams(reLayoutParams);
       linearLayout.setOrientation(LinearLayout.HORIZONTAL);
       linearLayout.setGravity(Gravity.CENTER);
       addView(linearLayout);
       dots = new ArrayList();
       // 设置当前选中
       int current = currentNumber % imgs.length;
       for (int i = 0; i < imgs.length; i++) {
           View view = new View(getContext());
           if (current == i) {
               view.setBackgroundResource(R.drawable.dot_focused);
           } else {
               view.setBackgroundResource(R.drawable.dot_normal);
           }
           LinearLayout.LayoutParams layoutparams = new LinearLayout.LayoutParams(
                   30, 30);
           layoutparams.setMargins(8, 0, 8, 0);
           view.setLayoutParams(layoutparams);
           linearLayout.addView(view);
       }
   }

}

MainActivity:

customerViewPagerComponent = (CustomerViewPagerComponent) findViewById(R.id.customerViewPager);

customerViewPagerComponent.setImgs(imgs);//imgs是图片数组，可以是图片id,也可以是网络图片的url

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