RecyclerView图片加载不显示？可能是这几个原因

glide.with(context)
    .load(imageurl)
    .placeholder(r.drawable.placeholder)
    .into(imageview)

Glide.with(context)
    .load(imageUrl)
    .addListener(object : RequestListener<Drawable> {
        override fun onLoadFailed(e: GlideException?, model: Any?, target: Target<Drawable>?, isFirstResource: Boolean): Boolean {
            return false
        }

        override fun onResourceReady(resource: Drawable?, model: Any?, target: Target<Drawable>?, dataSource: DataSource?, isFirstResource: Boolean): Boolean {
            // 根据图片宽高比设置 ImageView 的高度
            val width = imageView.width
            val aspectRatio = resource!!.intrinsicWidth.toFloat() / resource.intrinsicHeight.toFloat()
            val height = Math.round(width / aspectRatio)
            imageView.layoutParams = ViewGroup.LayoutParams(width, height)
            return false
        }
    })
    .into(imageView)