ActionButton(@DrawableRes imageResource: Int, contentDescription: String, visible: () -> Boolean = { true }, @DrawableRes background: Int? = null, listener: () -> Unit)
An action button to be added to the toolbar.
imageResource - The drawable to be shown.
contentDescription - The content description to use.
visible - Lambda that returns true or false to indicate whether this button should be shown.
background - A custom (stateful) background drawable resource to be used.
listener - Callback that will be invoked whenever the button is pressed