Swift 2.2 Warnings and It’s Solutions – Xcode 7.3

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Xcode 7.3 came with Swift 2.2 Version. I just updated to Xcode 7.3 and found following warnings because of Swift version change.

List of warnings with it’s solution:

  1. ‘var’ parameters are deprecated and will be removed in Swift 3
  2. Warning Function Var
    Warning Function Var

    Warning with:

    func functionTest(var param:String) {
    	print(param)
    }
    

    Solution:

    func functionTest(param:String) {
    	print(param)
    }
    

    If you want to update that variable inside the function then you have to create copy of that variable to do operations on that.

  3. Use of string literal for Objective-C selectors is deprecated; use ‘#selector’ instead
  4. Warning Selector
    Warning Selector

    Warning with:

    btn.addTarget(self, action: "functionName", forControlEvents: UIControlEvents.TouchUpInside)
    

    OR

    btn.addTarget(self, action: Selector("functionName"), forControlEvents: UIControlEvents.TouchUpInside)
    

    Solution:

    btn.addTarget(self, action: #selector(ViewController.functionName), forControlEvents: UIControlEvents.TouchUpInside)
    

    Apple Documentation : Added information about the #selector syntax for Objective-C selectors to the Selector Expression section.

  5. ‘++’ is deprecated: it will be removed in Swift 3
  6. Warning ++
    Warning ++

    Warning with:

    var i = 0
            
    for str in arrStr {
    	print(str)
    	i++
    }
    

    Solution:

    var i = 0
            
    for str in arrStr {
    	print(str)
    	i += 1
    }
    

    Apple Documentation : Removed discussion of C-style for loops, the ++ prefix and postfix operators, and the — prefix and postfix operators.

  7. C-style for statement is deprecated and will be removed in a future version of Swift
  8. Warning For Statement
    Warning For Statement

    Warning with:

    for var i=0; i<arrStr.count; i += 1 {
    	print(arrStr[i])
    }
    

    Solution:

    for i in 0 ..< arrStr.count {
    	print(arrStr[i])
    }
    

  9. __FILE__ is deprecated and will be removed in Swift 3, please use #file
  10. Warning __FILE__
    Warning __FILE__

    Warning with:

    __FILE__
    

    Solution:

    #file
    

More swift tutorials/articles are available here.

Happy Coding 🙂

How to create a wrapper for Alamofire and SwiftyJSON? Swift – iOS

This blogpost updated with Swift 3 – Xcode 8 – iOS 10 – Alamofire 4.0

AFWrapper
AFWrapper

I have posted a basic tutorial about Alamofire and SwiftyJSON How to use Alamofire and SwiftyJSON with Swift?

And some day before we have learned about Use of Blocks(Closures) or Completion Handlers with Function in Swift – iOS

Let’s combine both the topics to make a WRAPPER of Alamofire and SwiftyJSON.
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Use of Blocks(Closures) or Completion Handlers with Function in Swift – iOS

Blocks in Objective-C

In Objective-C we are using the blocks(completion handlers) with functions as follows :

- (void)yourFunctionName:(NSString *)yourString withCompletionHandler:(void (^)(NSString *yourResult))block;

Closures in Swift

Closures are self-contained blocks of functionality that can be passed around and used in your code. Closures in Swift are similar to blocks in C and Objective-C and to lambdas in other programming languages.

Syntax with Function

func yourFunctionName(parameter:Type, ... , withCompletionHandler:(result:Type) -> Void)

For more closure syntax : goshdarnclosuresyntax.com

Example

Function Definition:

func closureReturn(isTest:Bool, withCompletionHandler:(result:String) -> Void) {
    if(isTest){
        withCompletionHandler(result: "Yes")
    }
    else{
        withCompletionHandler(result: "No")
    }
}

Calling Function:

closureReturn(true) { (result) -> Void in
    print(result)
}

Output should be respective to value true/false.


In next post I will write a tutorial on a wrapper class for Alamofire with use of SwiftyJSON by using closures.

It will be related to this post How to use Alamofire and SwiftyJSON with Swift? – Swift 2 – iOS 9 – Xcode 7

Happy Coding 🙂

Work with Core Data in Swift Language

Lets take a brief idea about how to use core data with swift language.

Create a new project by check on Use Core Data.

Core Data Project Setting
Core Data Project Setting

It will create the basic methods of core data in to the AppDelegate.swift

There is core data model called {YOUR-PROJECT.xcdatamodeld} will be there with the project.

It will be look like as follows :

Core Data Model
Core Data Model

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