State animations

CompundButton.kt

class CompoundButton : BaseCompoundView {
  
    override fun loadAttrs(attrs: AttributeSet) {
        val styledAttrs = context.obtainStyledAttributes(attrs, R.styleable.CompoundButton, 0, 0)
        val iconStyleableId = R.styleable.CompoundButton_xxx
        imageView.setImageDrawable(StateListDrawable().apply {
            setFadeDuration(FADE_DURATION)
            addState(STATE_ACTIVE, getDrawable(styledAttrs, iconStyleableId, colorActive))
            addState(STATE_PRESSED, getDrawable(styledAttrs, iconStyleableId, colorLeftIconBacgroundPressed))
        })
        styledAttrs.recycle()
    }

...
  
    companion object {
        private val STATE_ACTIVE = intArrayOf(-android.R.attr.state_pressed)
        private val STATE_PRESSED = intArrayOf(android.R.attr.state_pressed)
        private const val FADE_DURATION = 80
    }
}

fun Drawable.setColor(color: Int) = this.mutate().setColorFilter(color, PorterDuff.Mode.SRC_ATOP)