Android ImageView scale smaller image to width with flexible height without cropping or distortion

Question

Often asked, never answered (at least not in a reproducible way).

I have an image view with an image that is smaller than the view. I want to scale

Answer 1

Kotlin version of Mark Martinsson's answer:

class DynamicImageView(context: Context, attrs: AttributeSet) : AppCompatImageView(context, attrs) {
override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
    val drawable = this.drawable

    if (drawable != null) {
        //Ceil not round - avoid thin vertical gaps along the left/right edges
        val width = View.MeasureSpec.getSize(widthMeasureSpec)
        val height = Math.ceil((width * drawable.intrinsicHeight.toFloat() / drawable.intrinsicWidth).toDouble()).toInt()
        this.setMeasuredDimension(width, height)
    } else {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
    }
}

Answer 2

There is no viable solution within the XML layout standard.

The only reliable way to react to a dynamic image size is to use LayoutParams in code.

Disappointing.