ViewPager画廊模式

最新推荐文章于 2021-11-16 15:10:50 发布

原创最新推荐文章于 2021-11-16 15:10:50 发布 · 209 阅读

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本文介绍如何在Android应用中自定义ViewPager的滑动效果，包括实现缩放和平移的过渡动画，并展示了如何使用Glide加载图片以及创建适配器。

首先创建一个Util类

public class ZoomOutSlideTransformer extends ABaseTransformer {

   private static final float MIN_SCALE = 0.85f;
   private static final float MIN_ALPHA = 0.5f;

   @Override
   protected void onTransform(View view, float position) {
      if (position >= -1 || position <= 1) {
         // Modify the default slide transition to shrink the page as well
         final float height = view.getHeight();
         final float width = view.getWidth();
         final float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
         final float vertMargin = height * (1 - scaleFactor) / 2;
         final float horzMargin = width * (1 - scaleFactor) / 2;

         // Center vertically
         view.setPivotY(0.5f * height);
         view.setPivotX(0.5f * width);

         if (position < 0) {
            view.setTranslationX(horzMargin - vertMargin / 2);
         } else {
            view.setTranslationX(-horzMargin + vertMargin / 2);
         }

         // Scale the page down (between MIN_SCALE and 1)
         view.setScaleX(scaleFactor);
         view.setScaleY(scaleFactor);

         // Fade the page relative to its size.
         view.setAlpha(MIN_ALPHA + (scaleFactor - MIN_SCALE) / (1 - MIN_SCALE) * (1 - MIN_ALPHA));
      }
   }

之后

 mVp = view.findViewById(R.id.pager);
 imageView = view.findViewById(R.id.hottest_image);

 mVp.setPageMargin(60);//控制两幅图之间的间距,尽量以屏幕的宽度来确定
 mVp.setPageTransformer(true,new ZoomOutSlideTransformer());
 //3D画廊模式
 mVp.setPageTransformer(true,new ZoomOutSlideTransformer());//3D画廊模式 //

mVp.setOffscreenPageLimit(list.size());//设置预加载数量
mVp.setAdapter(myAdapter);
Glide.with(context).load(list.get(0)).bitmapTransform(new BlurTransformation(context,35)).into(imageView);

适配器

public class MyAdapter extends PagerAdapter{
    private List<String> list;
    private Context context;

    public MyAdapter(List<String> list, Context context) {
        this.list = list;
        this.context = context;
    }

    @Override
    public int getCount() {
        return list.size();
    }
    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view == object;
    }

    @Override
    public Object instantiateItem(ViewGroup container, final int position) {
        ImageView imageView = new ImageView(context);
        SimpleDraweeView simpleDraweeView = new SimpleDraweeView(context);
       //设置图片进行展示  setImageResource 对应SRC
        ImageLoader.getInstance().displayImage(list.get(position),imageView, MApp.getoPetions());
        Log.i("TT",list.size()+"DDDD");
        //将图片拉伸
        imageView.setScaleType(ImageView.ScaleType.FIT_XY);
      // simpleDraweeView.setImageURI(Uri.parse(list.get(position)));
        //一个视图的组  每次加载前后中3张图片
        container.addView(imageView);
        imageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                onClick.setOnClickPosition(position);
            }
        });
        return imageView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        container.removeView((View) object);
    }
   OnClick onClick;
    public void setOnClick(OnClick onClick) {
        this.onClick = onClick;
    }
    public interface OnClick{
        void setOnClickPosition(int position);
    }
}