AutoMaxLinesTextView for Android (Kotlin)

AutoMaxLinesTextView.kt

class AutoMaxLinesTextView @JvmOverloads constructor(
  context: Context,
  attrs: AttributeSet? = null,
  defStyleAttr: Int = android.R.attr.textViewStyle
) : AppCompatTextView(context, attrs, defStyleAttr) {

  override fun onLayout(
    changed: Boolean,
    left: Int,
    top: Int,
    right: Int,
    bottom: Int
  ) {
    super.onLayout(changed, left, top, right, bottom)

    if (movementMethod is ScrollingMovementMethod) return

    val contentHeight = height - (paddingTop + paddingBottom)
    if (gravity and Gravity.TOP == Gravity.TOP) {
      for (line in lineCount - 1 downTo 0) {
        if (layout.getLineBottom(line) < contentHeight) {
          maxLines = line + 1
          break
        }
      }
    } else if (gravity and Gravity.BOTTOM == Gravity.BOTTOM) {
      for (line in 0..lineCount) {
        if (layout.getLineTop(line) > contentHeight) {
          maxLines = line - 1
          break
        }
      }
    }
  }
}