Set runtime margin to any view using Kotlin

This is how I would like to do in Kotlin -

fun View.margin(left: Float? = null, top: Float? = null, right: Float? = null, bottom: Float? = null) {
    layoutParams<ViewGroup.MarginLayoutParams> {
        left?.run { leftMargin = dpToPx(this) }
        top?.run { topMargin = dpToPx(this) }
        right?.run { rightMargin = dpToPx(this) }
        bottom?.run { bottomMargin = dpToPx(this) }
    }
}

inline fun <reified T : ViewGroup.LayoutParams> View.layoutParams(block: T.() -> Unit) {
    if (layoutParams is T) block(layoutParams as T)
}

fun View.dpToPx(dp: Float): Int = context.dpToPx(dp)
fun Context.dpToPx(dp: Float): Int = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, resources.displayMetrics).toInt()

now we just have to call this on a view like

textView.margin(left = 16F)

Here's a useful Kotlin extension method:

fun View.setMargins(
    left: Int = this.marginLeft,
    top: Int = this.marginTop,
    right: Int = this.marginRight,
    bottom: Int = this.marginBottom,
) {
    layoutParams = (layoutParams as ViewGroup.MarginLayoutParams).apply {
        setMargins(left, top, right, bottom)
    }
}

Use it like this:

myView.setMargins(
   top = someOtherView.height
   bottom = anotherView.height
)

EDIT: the solution is similar to the answer from Hitesh, but I'm using the (original) ViewGroup.setMargins in pixels. Of course you can make your own setMarginsDp variant based on these examples, or use Hitesh's dpToPx extension before calling my implementation. Whichever solution you choose depends on your own taste.

Also take note that my solution (re)sets all margins, although this won't be an issue in most cases.

You need to get the layoutParams object from button and cast it to ViewGroup.MarginLayoutParams (which is a parent class of LinearLayout.LayoutParams, RelativeLayout.LayoutParams and others and you don't have to check which is btnClickMe's actual parent) and set margins to whatever you want.

Check following code:

val param = btnClickMe.layoutParams as ViewGroup.MarginLayoutParams
param.setMargins(10,10,10,10)
btnClickMe.layoutParams = param // Tested!! - You need this line for the params to be applied.

Hope it helps.