Collection element of type 'double' is not an Objective-C object

Question

The inY property gives an error. What is the correct syntax?

UIButton *optionButton = [UIButton buttonWithType:UIButtonTypeCustom];
NSObject* anim = @{@"target": target, @"inY": infoView.frame.size.height-100, @"outY": @800};

Tried creating a variable with it as done with optionButton but it doesn't seem to work. I presume I need to cast it as something the collection can understand.

Excepting

Answer 1

infoView.frame.size.height-100 is a float. You can't cast it, you need to box it in an NSNumber (similar to what you've done with the 800 value for outY):

@(infoView.frame.size.height-100)

Candra

Thanks! was trying with {} but () was exactly what I needed. – Excepting

Answer 2

Try [NSNumber numberWithDouble:xxx]

This will then create an Objective-C NSNumber object which contains the double.

Bubb

@(xxx) does exactly the same, and is more modern, concise and readable. – Pesade

@() @[] @{} @## is the recommended literal syntax that you should use – Foreleg