Swift: Call function from another class - ios

So while I do see other examples of this online. None of them seem to work for me. I am trying to unhide my PinPadView class by calling it from the ViewController. Any suggestions would be greatly appreciated.
class ViewController: UIViewController, UIWebViewDelegate {
func initPinLogin() {
//Display the Pin Pad object in App
PinPadView.loadPinPad()
}
}
class PinPadView: UIView {
class func loadPinPad() {
let pinPad:PinPadView = PinPadView()
pinPad.hidden = false
}
}
Edit:
I have answered my question below. It was a newbie mistake, but for those who are having similar issues and want to see what I did, it is there.

You are creating a new instance of the object
let pinPad:PinPadView = PinPadView()
which you are un-hiding.
Instead reference the object which you want to hide from your VC class.

Thanks to everyone for the input. I have figured out what I was trying to do. I did not have to call the function from another class but rather create an outlet in the ViewController
#IBOutlet weak var pinPad: PinPadView!
after I did that, I was very easily able to do this
func initPinLogin() {
//Display the Pin Pad object in App
pinPad.hidden = false
}

Try tis:
class ViewController: UIViewController, UIWebViewDelegate {
func initPinLogin() {
let pinPad:PinPadView = PinPadView()
pinPad.loadPinPad()
}
}
class PinPadView: UIView {
class func loadPinPad() {
self.hidden = false
}
}

Related

Delegating action through protocol not working swift

I needed to delegate a click action for my UIView class to my UIViewController class since Swift does not support multiple class inheritance. So i wanted it such that once a button is clicked on my subview, a function in my BrowserViewController class is called.
I am using a protocol to achieve this, but on the function does not triggered when the button is tapped. Please help me out.
View Controller
class BrowseViewController: UIViewController {
var categoryItem: CategoryItem! = CategoryItem() //Category Item
private func setupExplore() {
//assign delegate of category item to controller
self.categoryItem.delegate = self
}
}
// delegate function to be called
extension BrowseViewController: ExploreDelegate {
func categoryClicked(category: ProductCategory) {
print("clicked")
let categoryView = ProductByCategoryView()
categoryView.category = category
categoryView.modalPresentationStyle = .overCurrentContext
self.navigationController?.pushViewController(categoryView, animated: true)
}
}
Explore.swift (subview)
import UIKit
protocol ExploreDelegate: UIViewController {
func categoryClicked(category: ProductCategory)
}
class Explore: UIView {
var delegate: ExploreDelegate?
class CategoryItem: UIView {
var delegate: ExploreDelegate?
var category: ProductCategory? {
didSet {
self.configure()
}
}
var tapped: ((_ category: ProductCategory?) -> Void)?
func configure() {
self.layer.cornerRadius = 6
self.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(self.categoryTapped)))
self.layoutIfNeeded()
}
#objc func categoryTapped(_ sender: UIGestureRecognizer) {
delegate?.categoryClicked(category: ProductCategory.everything)
self.tapped?(self.category)
}
}
}
Simply add a print statement inside categoryTapped.
You will then know if it is actually being tapped.
A million things could go wrong, for example, you may have forget to set the UIView to allow intertaction.
After checking that. Next add another print statement inside categoryTapped which shows you whether or not the delegate variable is null.
You'll quickly discover the problem using simple print statements.
print("I got to here!")
It's that easy.
And what about
if delegate == nil { print("it is nil!! oh no!" }
else { print("phew. it is NOT nil.") }
Debugging is really that easy at this level.
Next add a print statement inside setupExplore()
func setupExplore() {
print("setup explore was called")
....
See what happens.
I don't see any piece of code which sets the delegate.
First of all, define delegate as a property inside CategoryItem class, Then you must set the current instance of BrowseViewController to the delegate variable of CategoryItem. Now you can expect your method being called.
There are a few things that could cause the delegate method to not be triggered in this code:
Ensure that isUserInteractionEnabled = true on your CategoryItem. This is probably best done in either the configure() function in the CategoryItem or in the setupExplore() function of the BrowseViewController.
Make sure that the setupExplore() function on the BrowseViewController is being called, and that the category is being set on the CategoryItem to trigger the configure function. Otherwise, either the delegate or the gesture recognizer might not being set.
Side Note - weak vs strong delegate
On a side note, it is usually best practice to make your delegate properties weak var rather that having them be a strong reference, as this makes them prone to strong retain cycles.
Therefore, you might want to consider making the var delegate: ExploreDelegate? on your CategoryItem into weak var delegate: ExploreDelegate?. For more information on this problem, view this post.

How to implement didTapCheckBox of BEMCheckBox IOS Library?

I am new in Ios and i am having hard time wrapping my head around protocols and delegates concept. I am implementing a library called BEMCheckBox https://github.com/Boris-Em/BEMCheckBox or https://cocoapods.org/pods/BEMCheckBox for implementing radio buttons. Its documentation is pretty descriptive using which i have successfully added checkboxes, grouped them together to work as radio boxes.
#IBOutlet var inarelashipcb: BEMCheckBox!
#IBOutlet var complicatedcb: BEMCheckBox!
#IBOutlet var singlecb: BEMCheckBox!
var groupbx:BEMCheckBoxGroup!
func initialize(){
groupbx = BEMCheckBoxGroup(checkBoxes: [inarelashipcb,
complicatedcb, singlecb])
groupbx.selectedCheckBox = singlecb
groupbx.mustHaveSelection = true
}
Now i want to use didTapCheckBox method but i donot understand how. The documentation is blurry there no snippets for that. For the record this is what the documentation states
"BEMCheckBox uses a delegate to receive check box events. The delegate object must conform to the BEMCheckBoxDelegate protocol, which is composed of two optional methods:
didTapCheckBox:
Sent to the delegate every time the check box gets tapped, after its properties are updated (on), but before the animations are completed."
Any snippets to help me use delgate so i can implement didTapCheckBox method?
func initialize(){
groupbx = BEMCheckBoxGroup(checkBoxes: [inarelashipcb,
complicatedcb, singlecb])
groupbx.selectedCheckBox = singlecb
groupbx.mustHaveSelection = true
for checkbox in groupbx {
checkbox.delegate = self
}
}
must call initialize in viewDidLoad of the viewController
override func viewDidLoad() {
// Do your work
initialize()
}
compiler will show you an error, error will be gone if you add this codes
extension ViewController : BEMCheckBoxDelegate {
func didTap(_ checkBox: BEMCheckBox) {
//do your work
// if you have multiple checkboxes, then do like that
//if checkBox == checkBox1 {
//do work for checkbox1
//} else if {
// ..
//}
}
}
Don't forget to add the following line
import BEMCheckBox
The outlet checkbox you have declared, set delegate to self.
For eg, if your checkbox outlet is checkbox1 set its delegate as
checkbox1.delegate = self
I solve it.
using this code
func initialize(){
groupbx = BEMCheckBoxGroup(checkBoxes: [inarelashipcb,
complicatedcb, singlecb])
groupbx.selectedCheckBox = singlecb
groupbx.mustHaveSelection = true
inarelashipcb.delegate = self
complicatedcb.delegate = self
singlecb.delegate = self
}
func didTap(_ checkBox: BEMCheckBox) {
print("here hello")
}
Also my uiviewcontroller inherited from BEMCheckBoxDelegate

How to set UIView delegate?

I have an UIViewController
class WelcomeViewController: UIViewController
and an UIView
class SignUpView: UIView
Now I want to set in my WelcomeViewController delegate of SignUpView:
protocol SegueDelegate {
func runSegue(identifier: String)
}
class SignUpView: UIView { ... }
and connect it in
class WelcomeViewController: UIViewController, SegueDelegate {
how can I set in my WelcomeViiewController those delegate? When I'm trying to set:
override func viewDidLoad() {
SignUpView.delegate = self
}
it returns me
Instance member 'delegate' cannot be used on type 'SignUpView'
how can I find a solution?
You are trying to set delegate to a class. It should be an instance of the class i.e
let signUpView = SignUpView()
signUpView.delegate = self
What would be the point in doing that? If you want to navigate from one View to another, just add that Segue in Storyboard with an Identifier, so you can call self.performSegueWithIdentifier("IdentifierOfSegue", sender: self)
Create a weak property in SignUpView of that delegate(protocol) and name it other than delegate
then you can set and use it.
I agree with the developers saying "you can just do that via segue" but
the problem is you didn't declare a delegate var in the SignUpView class
so you can implement it in the signIn , if you declared it please write the line of code for me in a comment to check it
for now ...
I can suggest that you make a subview to be a parent class then override
which method you want to call
and you need to declare the delegate var as an optional (so you won't have
a memory cycle) like the following line ...
var delegate: SegueDelegate?
Let's solve this for people in need whom could need a solution when reading this issue:
In your UIView:
class SignUpView: UIView
you need to add:
var delegate : SegueDelegate?
Now, still in your class SignUpView, you need to add the function you want to delegate, just like this:
func runSegue(identifier: String) {
delegate?.runSegue(identifier)
}
This will call your delegate:
protocol SegueDelegate {
func runSegue(identifier: String)
}
Now, in your ViewController, you should have your SignUpView somewhere (created programmatically or linked through Storyboard / XIB).
In your viewDidLoadfunction, add: signUpView.delegate = self.
Don't forget to add SegueDelegatein your class heritage.

(Swift) ViewController's UI-elements can not be edited by implemented delegate method

I want to update the label in the DetailViewController everytime I selected a tableRow in the MasterViewController. To achieve this, I designed a delegate, which I have in the MasterVC
protocol TestTableViewControllerDelegate {
func selectedRow(selectedCar : Car)
}
class TestTableViewController: UITableViewController {
...
var delegate : TestTableViewControllerDelegate?
override func viewDidLoad() {
super.viewDidLoad()
self.delegate = DetailViewController()
The delegate works just fine, (it is implemented correctly in the DetailVC), it can pass values from TestTableVC to DetailVC and also correctly do println(), which prints a new Car.model String to the console every time I select a row in the TTVC.
The DetailVC looks like this (shortened):
class DetailViewController: UIViewController, TestTableViewControllerDelegate {
#IBOutlet var textLabel: UILabel!
var theCar : Car? {
didSet(newCar) {
refreshUI()
}
}
override func viewDidLoad() {
super.viewDidLoad()
refreshUI()
}
func selectedRow(selectedCar : Car) {
theCar = selectedCar
refreshUI()
}
func refreshUI() {
textLabel?.text = theCar!.model
}
}
I can achieve any kind of action with my delegate, expect for refreshing the UI. I have tried numerous ways, this is my latest attempt. Before that, I tried setting the textLabel's text property directly within the delegate method, didn't work. This problem only occurs when working with the UI-elements. I know it has something to do with the view not being loaded yet, but why does my refreshUI() function not work at all?
I am still a beginner, so any tip or help would be much appreciated!
A workaround I've used is to cerate a properly in the delegate and pass the value to it instead of the UI element. When the view loads I update the label's text properly with the value of the delegates property. I would think there's a better way to do this (I'm new to programming) but this is the best soultion I've come up with so far. Will update with sample code soon.

Delegate loosing View Controller objects swift

All,
I have set up a protocol, and the view controller is the delegate of this protocol, like so :
import Foundation
protocol PayButtonProtocol {
func enablePayButton()
func disablePayButton()
}
And the view controller is the delegate :
class ViewController: UIViewController, PayButtonProtocol
The protocol functions are as follows :
func enablePayButton() {
println("Button enabled")
PAYBarButton.enabled = false
}
func disablePayButton() {
PAYBarButton.enabled = false
}
I set a class and assign the delegate :
class Trigger
{
var delegate:PayButtonProtocol?
func EnablePayButton()
{
delegate?.enablePayButton()
}
}
Then I set the trigger to run the function :
let localtrigger = Trigger()
localtrigger.delegate = ViewController()
localtrigger.EnablePayButton()
This works and the 'button enabled' is displayed in the console. But the Bar Button (PAYBarButton) is nil and it seems that the view controller has lost its hieracy as I cannot access any of the view controllers objects. The View Controller was built with interface builder. Anyone got any ideas ? Is it
localtrigger.delegate = ViewController()
that rebuilds the viewconotroller and makes the original one not accessible ? If so how do i do this ?
if you are creating the localTrigger object inside your ViewController class you can just do:
let localtrigger = Trigger()
localtrigger.delegate = self // self is an instance of ViewController
localtrigger.EnablePayButton()

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