danielpunkass/ActionKit

Easy, closure-based Swift methods for working with interactive UIKit elements.

ActionKit

ActionKit is a light-weight, easy to use framework that wraps the target-action design paradigm into a less verbose, cleaner format. It shortens target-action method calls by removing the target and replacing the selector with a closure.

Example of target-action without ActionKit

button.addTarget(self, action: #selector(MyViewController.buttonWasTapped(_:)), forControlEvents: .TouchUpInside)

and somewhere else...

func buttonWasTapped(sender: Any) {
  if let button = sender as? UIButton {
    button.setTitle("Button was tapped!", forState: .Normal)
  } 
}

Or with ActionKit, all in one place

button.addControlEvent(.touchUpInside) { (control: UIControl) in
  guard let button = control as? UIButton else {
    return
  }
  button.setTitle("Button was tapped!", forState: .Normal)

}

Installation

CocoaPods

ActionKit is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'ActionKit', '~> 2.3.0'

Carthage

• 1. Add the following to your Cartfile:

    github "ActionKit/ActionKit" == 2.3.0

• 2. Run carthage update
• 3. Add the framework as described in Carthage Readme

How it works

ActionKit extends target-action functionality by providing easy to use methods that take closures instead of a selector. ActionKit uses a singleton which stores the closures and acts as the target. Closures capture and store references to any constants and variables from their context, so the user is free to use variables from the context in which the closure was defined in.

Features

• Add an action based closure to any UIGestureRecognizer subclass (eg. UITapGestureRecognizer, UIPanGestureRecognizer...) instead of needing to use the target-action mechanism
• Remove actions added to UIGestureRecognizer subclasses
• Add an action based closure to any UIControl subclass (eg: UIButton, UIView, UISwitch...) instead of needing to use the target-action mechanism
• Remove actions added to UIControl subclasses
• Add an action based closure to any UIBarButtonItem, instead of needing target-action
• Remove actions added to UIBarButtonItems

Methods: UIControl

Adding an action closure for a control event

- addControlEvent(_ controlEvents: UIControlEvents, _ closure: @escaping () -> ())

- addControlEvent(_ controlEvents: UIControlEvents, _ controlClosure: @escaping (UIControl) -> ())

Examples

addControlEvent, empty closure

- addControlEvent(_ controlEvents: UIControlEvents, _ closure: @escaping () -> ())

usable for UIButton

button.addControlEvent(.touchUpInside) {
  
  self.button.setTitle("Button was tapped!", forState: .Normal)

}

or any UIControl

switch.addControlEvent(.valueChanged) {
  [weak self]
  self?.demoLabel.text = "Switch value changed!"
}

Notes

When no closure parameter is given, be aware that any references to the original control are by default a strong reference to that object. However, as shown in the second example by adding the [weak self] annotation, this is instead a weak reference and will not risk causing a retain cycle.

addControlEvent, UIControl closure

- addControlEvent(_ controlEvents: UIControlEvents, _ controlClosure: @escaping (UIControl) -> ())

usable for UIButton

button.addControlEvent(.touchUpInside) { (control: UIControl) in
    guard let button = control as? UIButton else {
      return
    }
    button.setTitle("Button was tapped!", forState: .Normal)

}

or any UIControl

switch.addControlEvent(.valueChanged) { (control: UIControl) in
  [weak self]
  guard let switch = control as? UISwitch,
        let strongSelf = self else {
          return
  }
  strongSelf.demoLabel.text = "Switch value changed!"
  switch.backgroundColor.toggle()
}

Notes

With a closure parameter, there can still be strong references to the parent class. This example shows how to use a guard to unwrap the weak self, and otherwise abort the closure. Once unwrapped, further optional chaining is unneeded, a nice syntactic outcome.

Removing an action closure for a control event

- removeControlEvent(controlEvents: UIControlEvents)

Example

button.removeControlEvent(.touchUpInside)

Notes

When a UIControl with associated actions is removed from it's superview, all associated actions are removed. This behavior can be overriden, but should be done at your own risk. This behavior currently ensures references to UIControls aren't kept longer than needed (and therefore causing a memory leak through a reference cycle).

Methods: UIGestureRecognizer

Initializing a gesture recognizer with an action closure

- init(_ name: String, closure: @escaping () -> ())

- init(_ name: String, gestureClosure: @escaping (UIGestureRecognizer) -> ())

Examples

init, empty closure

- init(_ name: String, closure: @escaping () -> ())

usable for UITapGestureRecognizer

var singleTapGestureRecognizer = UITapGestureRecognizer() {
  self.view.backgroundColor = UIColor.redColor()
}

or any other UIGestureRecognizer subclass

var panGestureRecognizer = UIPanGestureRecognizer() {
  [weak self]
  self?.view.backgroundColor = UIColor.redColor()
}

init, UIGestureRecognizer in closure

- init(_ name: String, gestureClosure: @escaping (UIGestureRecognizer) -> ())

usable for UITapGestureRecognizer

var singleTapGestureRecognizer = UITapGestureRecognizer() { (gesture: UIGestureRecognizer) in
  if gesture.state == .Began {
      let locInView = gesture.locationInView(self.view)
      ...
  }
}

or any other UIGestureRecognizer subclass

var panGestureRecognizer = UIPanGestureRecognizer() { (gesture: UIGestureRecognizer) in
  if gesture.state == .Cancelled || gesture.state == .Ended  {
      let locInView = gesture.locationInView(self.view)
      ...
  }
}

Adding an action closure to a gesture recognizer

- addClosure(name: String, closure: () -> ())

- addClosure(name: String, closureWithGesture: (UIGestureRecognizer) -> ())

Example

singleTapGestureRecognizer.addClosure("makeBlue") {
  self.view.backgroundColor = UIColor.blueColor()
}

Removing an action closure for a control event

- removeClosure(_ name: String)

Example

singleTapGestureRecognizer.removeClosure("makeBlue")

Notes

When a UIGestureRecognizer is no longer needed, any references kept in closures added to the gesture need to be removed. Either by calling removeClosure as shown above for each named closure, or by simply calling clearActionKit() on the gestureRecognizer which will remove all associated named closures for the recognizer.

Methods: UIBarButtonItem

Initializing a bar button item with an action closure.

without parameters:

// Init with image
- init(image: UIImage, landscapeImagePhone: UIImage? = nil, style: UIBarButtonItemStyle = .Plain, actionClosure: () -> Void)

// Init with title
- init(title: String, style: UIBarButtonItemStyle = .Plain, actionClosure: () -> Void)

// Init with barButtonSystemInit
- init(barButtonSystemItem systemItem: UIBarButtonSystemItem, actionClosure: () -> Void) 

with parameters:

// Init with image
- init(image: UIImage, landscapeImagePhone: UIImage? = nil, style: UIBarButtonItemStyle = .Plain, actionWithItem: UIBarButtonItem -> Void)

// Init with title
- init(title: String, style: UIBarButtonItemStyle = .Plain, actionWithItem: UIBarButtonItem -> Void)

// Init with barButtonSystemInit
- init(barButtonSystemItem systemItem: UIBarButtonSystemItem, actionWithItem: UIBarButtonItem -> Void) 

Examples

let titleItem = UIBarButtonItem(title: "Press me") { 
	print("Title item pressed")
}
		
let image = UIImage(named: "alert")!
let imageItem = UIBarButtonItem(image: image) { (item: UIBarButtonItem) in
	print("Item \(item) pressed")
}
		
let systemItem = UIBarButtonItem(barButtonSystemItem: .Action) { 
	print("System item pressed")
}

Adding an action closure for a bar button item

- addActionClosure(actionClosure: () -> ())

Example

titleItem.addActionClosure {
	print("new action")
}

Removing an action closure for a bar button item

- clearActionKit()

Example

titleItem.clearActionKit()

License

Licensed under the terms of the MIT license. See LICENSE file