Apr 14, 2024 · To import a set of Objective-C files into Swift code within the same app target, you rely on an Objective-C bridging header file to expose those files to Swift. Xcode offers to create this header when you add a Swift file to an existing Objective-C app, or an Objective-C file to an existing Swift app.

In Swift 1.2, downcasts must be either optional with as? or “forced failable” with as!. If you’re sure about the type, then you can force the cast with as! similar to how you would use an implicitly-unwrapped optional: // After Swift 1.2 var aView: UIView = someView() var …

Aug 13, 2021 · In Swift you can still use the "#if/#else/#endif" preprocessor macros (although more constrained), as per Apple docs. Here's an example: #if DEBUG let a = 2 #else let a = 3 #endif Now, you must set the "DEBUG" symbol elsewhere, though. Set it in the "Swift Compiler - Custom Flags" section, "Other Swift Flags" line.

Dec 17, 2014 · In Swift 4.2 and Xcode 10.1. You have 4 ways total to delay. Out of these option 1 is preferable to call or execute a function after some time.

@VyachaslavGerchicov If you don’t know a simpler way for Swift, which was also specified in the question, then this would be the simplest way, even of you don’t consider it simple in a more general context that would include Objective-C. (Also, this answer is basically a one-line one-time definition of an enum, the function and its call is ...

May 17, 2015 · To use C++ files directly, you should create an objective-C wrapper. You'll want the implementation (which should reside by itself in a .mm file) to contain Objective-C++ code (which is just Objective-C and C++ in one file), and the interface (which should be in its own .h header file) should contain pure Objective-C code, so you'll have to convert C++ types to …

Jun 3, 2014 · Swift let vs var. let - constant var - variable [Constant vs variable] [Struct vs Class] Official doc docs.swift.org says. The value of a constant can’t be changed once it’s set, whereas a variable can be set to a different value in the future. This terminology actually describes a reassign mechanism. Mutability

Jun 4, 2019 · The @State keyword is a @propertyWrapper, a feature just recently introduced in Swift 5.1. As explained in the corresponding proposal , it's sort of a value wrapper avoiding boilerplate code. Sidenote: @propertyWrapper has previously been called @propertyDelegate , but that has changed since.

Split is a native Swift method introduced in Swift 4, and it returns an array of Substring values. On the other hand, components are part of the NSString class and return an array of String values. If you need the result as String values and are working with native Swift types, split is …

Jun 4, 2014 · How to concatenate string in Swift? In Objective-C we do like. NSString *string = @"Swift"; NSString *resultStr = [string stringByAppendingString:@" is a new Programming Language"]; or. NSString *resultStr=[NSString stringWithFormat:@"%@ is a new Programming Language",string]; But I want to do this in Swift-language.