RecyclerView + StaggeredGridLayout +毕加索获取GridItem宽度

Question

我使用RecyclerView和StaggeredGrid (spanCount是可变的)。每个GridItem (一个CardView)包含一个正方形ImageView。我想要的是加载一个图像从我的后端与所需的宽度和高度，以完全适合CardView内的ImageView。有什么建议我可以做到这一点吗？代码示例如下：

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position) {
    Picasso.with(context)
        .load(String.format("http://mybackend.com/image/w_%d,h_%d/%s",
                holder.image.getMeasuredWidth(), // This returns 0, but i want here a real width
                holder.image.getMeasuredWidth(),
                myCollection.get(position).getImagePid()))
        .tag(context)
        .placeholder(R.drawable.placeholder_logo)
        .into(holder.image);

简而言之:在绑定我的ViewHolder之前，我需要以某种方式获得imageView维度(宽度)。

Answer 1

你有没有研究过使用.fit()？我相信这将调整图像的大小，使其完全适合ImageView。

Answer 2

您可以使用ViewTreeObserver

final int width = holder.image.getMeasuredWidth();
    if (width > 0) {
        Picasso.with(context)
                .load(String.format("http://mybackend.com/image/w_%d,h_%d/%s",
                        holder.image.getMeasuredWidth(), // This returns 0, but i want here a real width
                        holder.image.getMeasuredWidth(),
                        myCollection.get(position).getImagePid()))
                .tag(context)
                .placeholder(R.drawable.placeholder_logo)
                .into(holder.image);
    } else {
        holder.image.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                holder.image.getViewTreeObserver().removeGlobalOnLayoutListener(this);
                Picasso.with(context)
                        .load(String.format("http://mybackend.com/image/w_%d,h_%d/%s",
                                holder.image.getMeasuredWidth(), // This returns 0, but i want here a real width
                                holder.image.getMeasuredWidth(),
                                myCollection.get(position).getImagePid()))
                        .tag(context)
                        .placeholder(R.drawable.placeholder_logo)
                        .into(holder.image);
            }
        });
    }