如何实现带有不同行数的RecyclerView？

Question

I know that I can implement a RecyclerView with different views for items on Android.

But my need is a little bit different here. I would like to know how can I implement a RecyclerView with a different number of items by rows.

For example, I would have 2 items for first row, then just 1 item for second row, then 3 items for third row, ...

Is it possible to implement this with a RecyclerView? If so, How can I implement it?

Thanks for your help.

Sylvain

Answer 1

What you're looking for can be done with GridLayoutManager itself, the only trick here is to use the least common multiple (lcm) of your column counts per row as your total span count. Here is an easy example:

@Override
public void onCreate() {
    super.onCreate();

    ...

    int spanCount = lcm(2, 1, 3, 8);
    GridLayoutManager layoutManager = new GridLayoutManager(this, spanCount);
    layoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
        @Override
        public int getSpanSize(int position) {
            int numberOfColumns;
            switch (position) {
                case 0:
                    numberOfColumns = 2;
                    break;
                case 1:
                    numberOfColumns = 1;
                    break;
                case 2:
                    numberOfColumns = 3;
                    break;
                case 3:
                    numberOfColumns = 8;
                    break;
                default:
                    numberOfColumns = spanCount;
            }
            return spanCount / numberOfColumns;
        }
    });
    recyclerView.setLayoutManager(layoutManager);

    ...
}

public static int lcm(int... input) {
    int result = input[0];
    for(int i = 1; i < input.length; i++) result = lcm(result, input[i]);
    return result;
}

Answer 2

是的，有可能，您只需要创建不同的Views并将它们放入if (holder instanceof ProfileAdapter.VideoViewHolder) { } else { }然后使用public int getItemViewType(int position) { }将视图扔进上述方法中