Add opaque “shadow” (outline) to Android TextView

Question

I have a TextView in my Activity to which I want to add a shadow. It is supposed to look like in OsmAnd (100% opaque):

But it looks like this:

Answer 1

I experienced the same issue, with calling setTextColor in onDraw causing infinite draw loop. I wanted to make my custom text view have a different fill color than the outline color when it rendered text. Which is why I was calling setTextColor multiple times in onDraw.

I found an alternative solution using an OutlineSpan see https://github.com/santaevpavel/OutlineSpan. This is better than making the layout hierarchy complicated with multiple TextViews or using reflection and requires minimal changes. See the github page for more details. Example

val outlineSpan = OutlineSpan(
    strokeColor = Color.RED,
    strokeWidth = 4F
)
val text = "Outlined text"
val spannable = SpannableString(text)
spannable.setSpan(outlineSpan, 0, 8, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE)

// Set text of TextView
binding.outlinedText.text = spannable