How to declare blocks using Swift in iOS?

Question

I am trying to convert my Objective C source code to swift, I have searched alot to change syntax for Blocks.

Here is my Objective C code that I want to switch to Swift :

class.h file :

@property (nonatomic, copy) void (^tapBlock)(CGFlagsCell *);

+ (NSString *)cellIdentifier;

Class.m file :

self.tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(didTapCell)];

- (void)didTapCell {
    self.tapBlock(self);
}

I have converted the class method as class func cellIdentifier() -> String { return "yourValue" } please help me for the rest. Thanks! — Anand Gautam, Apr 26 '15 at 12:16
@ BoilingLime I want to convert my above objective C code to Swift for Blocks. My Objective C code is : @property (nonatomic, copy) void (^tapBlock)(CGFlagsCell *); — Anand Gautam, Apr 26 '15 at 12:36
If anyone can't help me, so why you guys are doing down vote.... If you are thinking that my question is not good for StackOverFlow.. then tell me the reason.. — Anand Gautam, Apr 26 '15 at 12:42

AliSoftware · Accepted Answer · 2015-04-26T12:52:06.000

0

In Swift, blocks, functions and closures are the same thing, they have the same signature and are interchangeable.

So this would give you something like this

var  tapBlock: CGFlagsCell -> Void

You can add parenthesis around the parameter (optional if there is only one, recommended if there are multiple input parameters) and around the return type (optional):

var tapBlock: (CGFlagsCell) -> (Void)

edited Apr 26 '15 at 12:52

answered Apr 26 '15 at 12:45

AliSoftware

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Thanks alot @AliSoftware for your help... It's working fine now, Can you please give me some idea for UITapGestureRecognizer if possible, As this is my custom UITableViewCell. – Anand Gautam Apr 26 '15 at 12:50
Thanks again @AliSoftware... But I don't know why down vote, anyway this will help to other programmers.. :) – Anand Gautam Apr 26 '15 at 12:55

score 0 · Answer 2 · answered Apr 26 '15 at 12:47

0

Define a closure a variable of your class :

var tapBlock: (parameterTypes) -> (returnType)

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 Objective-C

answered Apr 26 '15 at 12:47

BoilingLime

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How to declare blocks using Swift in iOS?

2 Answers2