iOS--Swift 3--SwiftAlertView--optional type

Question

I use the third party SwiftAlertView class(https://github.com/dinhquan/SwiftAlertView) and update Swift from 2.3 to 3.
When I complied, the app and I found the error message as following.

 Binary operator '+' cannot be applied to operands of type 'Double' and 'Double!'

The code is following.
The titleTopMargin and titleToMessageSpacing are Double!
That can't add Double(titleLabel.frame.size.height).

let topPartHeight = (contentView == nil) ? (titleTopMargin + Double(titleLabel.frame.size.height) + titleToMessageSpacing + Double(messageLabel.frame.size.height) + messageBottomMargin) : Double(contentView!.frame.size.height)

The definition is following.

// customize the margin & spacing of title & message
open var titleSideMargin: Double!  // default is 20 px
open var messageSideMargin: Double!  // default is 20 px
open var titleTopMargin: Double!  // default is 20 px
open var messageBottomMargin: Double! // default is 20 px
open var titleToMessageSpacing: Double! // default is 10 px

How do I fix the problem?

Thanks.

Could you show us where you define `titleTopMargin`, `titleToMessageSpacing`, and `messageBottomMargin`? The problem is likely that one (or more) of these are implicitly unwrapped. — T. Benjamin Larsen, Sep 30 '16 at 06:14
The issue is related to http://stackoverflow.com/questions/39251005/strange-generic-function-appear-in-view-controller-after-converting-to-swift-3 — vadian, Sep 30 '16 at 06:41

score 1 · Answer 1 · answered Oct 03 '16 at 07:58

Thanks everybody for giving me suggestion.

These variables still need to use Double. So I need to update the following code.

open var titleSideMargin: Double = 20.0
open var messageSideMargin: Double = 20.0
open var titleTopMargin: Double = 20.0
open var messageBottomMargin: Double = 20.0
open var titleToMessageSpacing: Double = 10.0

score 0 · Answer 2 · answered Sep 30 '16 at 06:16

0

UIKit and CoreGraphics always use CGFloat for size, they never use to Double type. So, I think we should use to CGFloat here.

answered Sep 30 '16 at 06:16

Rahul Mayani

3,761
4
25
40

score 0 · Answer 3 · answered Sep 30 '16 at 06:59

Exactly as @Rahul answers. So set type to CGFloat:

var titleSideMargin: CGFloat = 20.0
var messageSideMargin: CGFloat = 20.0
var titleTopMargin: CGFloat = 20.0
var messageBottomMargin: CGFloat = 20.0
var titleToMessageSpacing: CGFloat = 10.0

let topPartHeight = (contentView == nil) ? (titleTopMargin + titleLabel.frame.size.height + titleToMessageSpacing + messageLabel.frame.size.height + messageBottomMargin) : contentView!.frame.size.height

iOS--Swift 3--SwiftAlertView--optional type

3 Answers3