如何动态地将对象添加到CardViews的视图寻呼机？

Question

我正在努力实现类似于this的效果。我环顾四周，找到了与此类似的代码

ViewPagerAdapter

public class ViewPagerAdapter extends PagerAdapter {

    private Context mContext;
    private LayoutInflater mLayoutInflater;
    private ArrayList<SomeObject> someObjectList;

    public ViewPagerAdapter(Context context, ArrayList<SomeObject> someObjectList) {
        mContext = context;
        this.someObjectList = someObjectList;
        mLayoutInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public int getCount() {
        return someObjectList.size();
    }

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

    @NonNull
    @Override
    public Object instantiateItem(@NonNull ViewGroup container, int position) {
        View itemvView = mLayoutInflater.inflate(R.layout.content_main, container, false);

        SomeObject object = someObjectList.get(position);

        TextView tvTitle = itemvView.findViewById(R.id.textView);
        tvTitle.setText(object.getTitle());

        ImageView image = itemvView.findViewById(R.id.imageView);
        image.setImageResource(object.getImageResource());

        container.addView(itemvView);

        return itemvView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        container.removeView((LinearLayout) object);
    }

    public void addItems(List<SomeObject> someObject) {
        // TODO : Add objects dynamically without using notifyDataSetChanged()
    }

}

我还修改了自定义View Pager组件以满足我的需求

自定义视图寻呼机

class VerticalViewPager : ViewPager {

    private val MIN_SCALE = 0.75f

    constructor(context: Context) : super(context) {
        init()
    }

    constructor(context: Context, attrs: AttributeSet) : super(context, attrs) {
        init()
    }

    private fun init() {
        // The majority of the magic happens here
        setPageTransformer(true, VerticalPageTransformer())
        // The easiest way to get rid of the overscroll drawing that happens on the left and right
        overScrollMode = View.OVER_SCROLL_NEVER
    }

    private inner class VerticalPageTransformer : ViewPager.PageTransformer {
        override fun transformPage(view: View, position: Float) {

            when {
                position < -1 -> // [-Infinity,-1)
                    // This page is way off-screen to the left.
                    view.alpha = 0f
                position <= 0 -> { // [-1,0]
                    // Use the default slide transition when moving to the left page
                    view.alpha = 1f
                    // Counteract the default slide transition
                    view.translationX = view.width * -position

                    //set Y position to swipe in from top
                    val yPosition = position * view.height
                    view.translationY = yPosition
                    view.scaleX = 1f
                    view.scaleY = 1f

                }
                position <= 1 -> { // [0,1]
                    view.alpha = 1f

                    // Counteract the default slide transition
                    view.translationX = view.width * -position


                    // Scale the page down (between MIN_SCALE and 1)
                    val scaleFactor = MIN_SCALE + (1 - MIN_SCALE) * (1 - Math.abs(position))
                    view.scaleX = scaleFactor
                    view.scaleY = scaleFactor

                }
                else -> // (1,+Infinity]
                    // This page is way off-screen to the right.
                    view.alpha = 0f
            }
        }

    }

    /**
     * Swaps the X and Y coordinates of your touch event.
     */
    private fun swapXY(ev: MotionEvent): MotionEvent {
        val width = width.toFloat()
        val height = height.toFloat()

        val newX = ev.y / height * width
        val newY = ev.x / width * height

        ev.setLocation(newX, newY)

        return ev
    }

    override fun onInterceptTouchEvent(ev: MotionEvent): Boolean {
        val intercepted = super.onInterceptTouchEvent(swapXY(ev))
        swapXY(ev) // return touch coordinates to original reference frame for any child views
        return intercepted
    }

    override fun onTouchEvent(ev: MotionEvent): Boolean {
        return super.onTouchEvent(swapXY(ev))
    }
}

我在main_activity.xml中插入了自定义ViewPager视图，并在MainActivity.java中设置了适配器..

我需要动态无限地添加卡片项目。即数据将在用户滚动卡片堆栈时加载，并显示无限卡片。

因此，当卡片向下滚动时，我需要动态地向视图寻呼机添加对象。

正如我用Google搜索，向视图寻呼机添加更多数据的唯一方法是使用notifyDataSetChanged方法。但我不希望这样，因为随着数据量的增加它变得非常低效。＆＃39;

如何动态地向视图寻呼机添加更多数据？

我找到了通知活动何时加载的方法。我只需要弄清楚如何在不使用notifyDataSetChanged（）的情况下设置数据。