如何将主单元格放在 StaggeredGridLayout（回收器视图）的顶部？答案

【问题标题】：How to put main cell on the top of StaggeredGridLayout(recycler view)?如何将主单元格放在 StaggeredGridLayout（回收器视图）的顶部？
【发布时间】：2017-07-01 08:39:16
【问题描述】：

我在Recycler View 中使用StaggeredGridLayout

我需要什么：

我可以将回收站视图分成 2 列，但我不知道如何将主单元格放在回收站视图的顶部

我不确定，但也许我可以将它放在容器中并在滚动期间尝试隐藏它？就像我们在用户开始向上滚动工具栏时使用工具栏一样。

但我不确定

如何将主单元格放在 StaggeredGridLayout(recycler view) 的顶部？

提前致谢！

【问题讨论】：

所以，你需要一个标题。也许this 有帮助。

标签： java android android-recyclerview

【解决方案1】：

在 onBindViewHolder 方法中添加这些行

if(position == 0){
      StaggeredGridLayoutManager.LayoutParams layoutParams =  (StaggeredGridLayoutManager.LayoutParams) holder.itemView.getLayoutParams();
      layoutParams.setFullSpan(true);
}

【讨论】：

【解决方案2】：

最终我的适配器可能会帮助某人了解它是如何工作的

public class AdapterRecViewMain
    extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

private List<BaseMarkerElement> mainCardList;
private final int HEADER_VIEW = 0;
private final int FOOTER_VIEW = 1;

public AdapterRecViewMain() {
}

public void setData(List<BaseMarkerElement> mainCardList) {
    this.mainCardList = mainCardList;
}

@Override public int getItemViewType(int position) {
    if (position == 0) {
        return HEADER_VIEW;
    }
    return FOOTER_VIEW;
}

@Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int type) {
    if (type == FOOTER_VIEW) {
        View v = LayoutInflater.from(viewGroup.getContext())
                .inflate(R.layout.card_main_activity, viewGroup, false);
        return new MainCardViewHolder(v);
    } else {
        View v = LayoutInflater.from(viewGroup.getContext())
                .inflate(R.layout.header_view_main_activity, viewGroup, false);
        return new HeaderViewHolder(v);
    }
}

@Override public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int positionItem) {
    final int position = viewHolder.getAdapterPosition();

    if (viewHolder instanceof HeaderViewHolder) {
        StaggeredGridLayoutManager.LayoutParams layoutParams =
                (StaggeredGridLayoutManager.LayoutParams) viewHolder.itemView.getLayoutParams();
        layoutParams.setFullSpan(true);

        BaseMarkerElement item = mainCardList.get(position);
        if (item instanceof HeaderView) {
            HeaderView header = (HeaderView) mainCardList.get(position);
            // need to add implementation
        }
    } else if (viewHolder instanceof MainCardViewHolder) {
        MainCardViewHolder currentView = (MainCardViewHolder) viewHolder;
        CardMainActivity currentCard = (CardMainActivity) mainCardList.get(position);

        currentView.ivMainCard.setImageResource(currentCard.getIvMainCard());
        currentView.tvBrandName.setText(currentCard.getTvBrandName());
        currentView.tvPrice.setText(currentCard.getTvPrice());
        currentView.tvType.setText(currentCard.getTvType());
    }
}

@Override public int getItemCount() {
    return mainCardList.size();
}

private class MainCardViewHolder extends RecyclerView.ViewHolder {
    ImageView ivMainCard;
    TextView tvBrandName;
    TextView tvType;
    TextView tvPrice;

    MainCardViewHolder(View view) {
        super(view);
        ivMainCard = (ImageView) view.findViewById(R.id.imageViewMainCard);
        tvBrandName = (TextView) view.findViewById(R.id.tvBrandName);
        tvType = (TextView) view.findViewById(R.id.tvType);
        tvPrice = (TextView) view.findViewById(R.id.tvPrice);
    }
}

private class HeaderViewHolder extends RecyclerView.ViewHolder {

    public HeaderViewHolder(View itemView) {
        super(itemView);

    }
}
}

【讨论】：