Any SwiftUI view can be partially or wholly transparent using the
opacity() modifier. This accepts a value between 0 (completely invisible) and 1 (fully opaque), just like the
alpha property of
UIView in UIKit.
For example, this creates a text view with a red background, then gives it 30% opacity:
Text("Now you see me") .padding() .background(Color.red) .opacity(0.3)