I have a cell with a textField and a button. The button opens a page to collect data and has a protocol to pass that data back to the cell and fill the textField. That all works fine, however, when I come back the value is reset to zero. Print statements show that it is passing the data when it's set, but hitting Back clears it for some reason.
Protocol
protocol DistanceProtocol {
func distanceSet(distance: Double)
}
Call to protocol method
distanceProtocol?.distanceSet(totalDistance)
Cell class
class InputCell: CalculatorCell, DistanceProtocol {
#IBOutlet var textField: UITextField?
private var inputType = InputType.undefined
var viewController = UIViewController()
override func getHeight() -> CGFloat {
return 90
}
func distanceSet(distance: Double) {
print(distance)
textField?.text = "\(distance)"
}
func getInputType() -> InputType {
return inputType
}
func setInputType(inputType: InputType) {
self.inputType = inputType
}
#IBAction func walkTouched(sender: UIButton) {
let mapVc = viewController.storyboard!.instantiateViewControllerWithIdentifier("Map") as! MapLocationsViewController
mapVc.distanceProtocol = self
viewController.navigationController?.pushViewController(mapVc, animated: true)
}
}
As far as I can tell, everything is set up correctly. It's not reloading the cells in the tableView when I come back. Why is it resetting/how can I prevent it?
the text field is only set when you call the function. Unless you call this function in cellForRowAtIndex path it wont retain the value
I would likely implement it using a setter, do everytime the value is set, the label gets updated
protocol DistanceProtocol {
func distanceSet(distance: Double)
}
class CellWithText: UITableViewCell {
var cellText: String {
didSet {
textLabel?.text = cellText
}
}
}
extension CellWithText: DistanceProtocol {
func distanceSet(distance: Double) {
self.cellText = "\(distance)"
}
}
Then in your cellForRowAtIndexPath call you would call the function
cell.distanceSet(19.0)
i think you might try singleton design pattern or you can use struct for copying.
Related
I am working on two views that are subclassing subclass of UITableViewCell. In the base one (subclass of UITableViewCell) I am trying to setup gesture recognizer in a way that each of super class could change the behavior (eventually call didTapped method on it's delegate) of the tap.
I have written following code. I can use #selector(tap), however I think that using a variable instead of overriding a tap method in each super class is a much cleaner way. Is it even possible to use something like #selector(tapFunc)? If no what would be the cleanest and best from engineering point of view solution?
class BaseCell: UITableViewCell {
#objc var tapFunc: () -> () = { () in
print("Tapped")
}
#objc func tap() {
print("TEST")
}
func setupBasicViews(withContent: () -> ()) {
let tapGestureRecoginzer = UITapGestureRecognizer(target: self, action: #selector(tapFunc))
contentView.isUserInteractionEnabled = true
contentView.addGestureRecognizer(tapGestureRecoginzer)
}
}
And then two views that are building on top of this one:
class ViewA: BaseCell {
//don't want to do this
override func tap() {
//do stuff
}
func setup {
//setup everything else
}
class ViewB: BaseCell {
var delegate: ViewBProtocool?
func setup {
tapFunc = { () in
delegate?.didTapped(self)
}
//setup everything else
}
You're not too far off. Make the following changes:
class BaseCell: UITableViewCell {
var tapFunc: (() -> Void)? = nil
// Called by tap gesture
#objc func tap() {
tapFunc?()
}
func setupBasicViews(withContent: () -> ()) {
let tapGestureRecoginzer = UITapGestureRecognizer(target: self, action: #selector(tap))
contentView.isUserInteractionEnabled = true
contentView.addGestureRecognizer(tapGestureRecoginzer)
}
}
class ViewA: BaseCell {
func setup() {
//setup everything else
}
}
class ViewB: BaseCell {
var delegate: ViewBProtocol?
func setup() {
tapFunc = {
delegate?.didTapped(self)
}
//setup everything else
}
}
Now each subclass can optionally provide a closure for the tapFunc property.
I show above that tapFunc is optional with no default functionality in the base class. Feel free to change that to provide some default functionality if desired.
I am creating a custom subclass of UIControl (I need to override its draw method) and I want to add RxSwift to bind its isSelected property to my model.
So far so good. This works fine.
My problem is how can I do to change the value isSelected property in response of user touchUpInside event?.
My first try was to use the addTarget method of UIControl, but changing the value of isSelected programmatically is not reported by the ControlProperty (as stated in the doc). But I can figure another way to resolve this.
Any help appreciated.
Source code of the subclass:
class SYYesNoButton: UIControl {
override init(frame: CGRect) {
super.init(frame: frame)
// subscribe to touchUpInside event
addTarget(
self,
action: #selector(userDidTouchUpInside),
for: UIControlEvents.touchUpInside)
}
func userDidTouchUpInside() {
// change the value of the property
// this does not work,
// the change is not reported to the ControlProperty
// HOW CAN I CHANGE THIS ??
self.isSelected = !isSelected
}
}
Extensions to add reactive support:
extension SYYesNoButton {
var rx_isSelected: ControlProperty<Bool> {
return UIControl.valuePublic(
self,
getter: { (button) -> Bool in
return button.isSelected
},
setter: { (button, value) in
button.isSelected = value
})
}
}
extension UIControl {
static func valuePublic<T, ControlType: UIControl>(_ control: ControlType, getter: #escaping (ControlType) -> T, setter: #escaping (ControlType, T) -> ()) -> ControlProperty<T> {
let values: Observable<T> = Observable.deferred { [weak control] in
guard let existingSelf = control else {
return Observable.empty()
}
return (existingSelf as UIControl).rx.controlEvent([.allEditingEvents, .valueChanged])
.flatMap { _ in
return control.map { Observable.just(getter($0)) } ?? Observable.empty()
}
.startWith(getter(existingSelf))
}
return ControlProperty(values: values, valueSink: UIBindingObserver(UIElement: control) { control, value in
setter(control, value)
})
}
}
Thanks for all.
Once you have an actual UIControl, there's an even nicer way to a "native" RxCocoa extension called a ControlProperty using a helper method in RxCocoa.
For example:
extension Reactive where Base: someControl {
var someProperty: ControlProperty<Float> {
return controlProperty(editingEvents: .valueChanged,
getter: { $0.value },
setter: { $0.value = $1 })
}
}
This will expose the current value from the getter block whenever the specified UIControlEvent is fired, and will also set the value whenever some stream is bound to it.
It sort of acts like an Observable and Observer type together - you can observe its value, but can also subscribe to it.
If you are subclassing from UIControl, then you are making your own control class and you have to override one or more of beginTracking(_:with:), continueTracking(_:with:), endTracking(_:with:), or cancelTracking(with:) to make the control work the way you want. Then call sendActions(for:) with the correct event. The guts of a UIControl would not have Rx in it.
Taking a queue from UIButton, your control should not select itself, although it can highlight and unhighlight itself (when the user's finger is on it for example.)
Once you have properly created your UIControl, code outside the control can use Rx to observe it with no extra work on your part.
The following works (Updated for Swift 5/RxSwift 5):
class ViewController: UIViewController {
#IBOutlet weak var yesNoButton: SYYesNoButton!
private let bag = DisposeBag()
override func viewDidLoad() {
super.viewDidLoad()
yesNoButton.rx.controlEvent(.touchUpInside)
.scan(false) { v, _ in !v }
.bind(to: yesNoButton.rx.isSelected)
.disposed(by: bag)
}
}
#IBDesignable
class SYYesNoButton: UIControl {
override func layoutSubviews() {
super.layoutSubviews()
backgroundColor = isSelected ? .green : .red
}
override var isSelected: Bool {
didSet {
super.isSelected = isSelected
backgroundColor = isSelected ? .green : .red
}
}
}
I'm working on an NSOutlineView that uses NSView subclasses to generate custom cells in the outline. This I've gotten to work, BUT after the Outline sucks in the data from the model class and displays it correctly, the Outline is released(?) from memory / goes to nil and I haven't figured out a way to get it back.
Here is the MainViewController class
class MainWindowController: NSWindowController, ShareInfoDelegate, NSOutlineViewDelegate, NSOutlineViewDataSource {
override var windowNibName: String {
return "MainWindowController"
}
#IBOutlet var daOutline: NSOutlineView!
// The NSoutline I'm trying to get back to
Some stuff related to the test data (Omitted)
leading us to the NSOutlineViewDataSource stuff
//MARK: - NSOutlineViewDataSource
func outlineView(outlineView: NSOutlineView, child index: Int, ofItem item: AnyObject?) -> AnyObject {
if let item: AnyObject = item {
switch item {
case let work as Work:
return work.movements[index]
case let movement as Movement:
return movement.tracks[index]
default:
let track = item as! Track
return track.credits[index]
}
} else {
if allWorks.count > 0 {
return allWorks[index]
}
}
let q = "patience"
return q
}
func outlineView(outlineView: NSOutlineView, isItemExpandable item: AnyObject) -> Bool {
switch item {
case let work as Work:
return (work.movements.count > 0) ? true : false
case let movement as Movement:
return (movement.tracks.count > 0) ? true : false
case let track as Track:
return (track.credits.count > 0) ? true: false
default:
return false
}
}
func outlineView(outlineView: NSOutlineView, numberOfChildrenOfItem item: AnyObject?) -> Int {
if let item: AnyObject = item {
switch item {
case let work as Work:
return work.movements.count
case let movement as Movement:
return movement.tracks.count
case let track as Track:
return track.credits.count
default:
return 0
}
} else {
return allWorks.count
}
}
func outlineView(daOutline: NSOutlineView, viewForTableColumn theColumn: NSTableColumn?, item: AnyObject) -> NSView? {
switch item {
case let worked as Work:
let cell = daOutline.makeViewWithIdentifier("newTry", owner:self) as! newTry
cell.fourthLabel.stringValue = worked.composer
cell.fourthCell.stringValue = worked.title
return cell
case let moved as Movement:
let cell2 = daOutline.makeViewWithIdentifier("SecondTry", owner:self) as! SecondTry
cell2.roman.stringValue = moved.name!
cell2.details.stringValue = moved.sections!
cell2.track.stringValue = "0"
return cell2
default:
print("probably not")
}
print("not again")
return nil
}
func outlineView(daOutline: NSOutlineView, heightOfRowByItem item: AnyObject) -> CGFloat {
switch item {
case let worked as Work:
return 40
default:
return 24
}
}
And the stuff in WindowDidLoad
override func windowDidLoad() {
super.windowDidLoad()
let nib = NSNib(nibNamed: "newTry", bundle: NSBundle.mainBundle())
daOutline.registerNib(nib!, forIdentifier: "newTry")
let nib2 = NSNib(nibNamed: "SecondTry", bundle: NSBundle.mainBundle())
daOutline.registerNib(nib2!, forIdentifier: "SecondTry")
//give Sender it's Receiver
mailItOut.delegate = receiver
allWorks.append(work1)
allWorks.append(work2)
work1.movements.append(move1)
work1.movements.append(move2)
work1.movements.append(move3)
work1.movements.append(move4)
work2.movements.append(move5)
work2.movements.append(move6)
work2.movements.append(move7)
daOutline.reloadData()
daOutline?.expandItem(work1, expandChildren: false)
daOutline?.expandItem(work2, expandChildren: false)
}
}
And Finally what the newTry NSView class looks like
class newTry: NSView {
var delegate: ShareInfoDelegate?
#IBOutlet weak var fourthCell: NSTextField!
#IBOutlet weak var fourthLabel: NSTextField!
#IBAction func cellAdd(sender: NSTextField) {
var catchIt: String = String()
catchIt = sender.stringValue
if catchIt != "" {
tryAgain = catchIt
whichField = "title"
//Trigger the sender to send message to it's Receiver
mailItOut.sendMessage()
}
}
The cellAdd Action is used to try and get user input from the text cells back into the model. To do this I (AFAIK) need to access the NSOutline (daOutline) and get which row I'm at and put the data from the sender into the appropriate part of the Model class. Which is something that I've managed to get to work in a standard (1 cell / 1 data value) outline. But in this prototype, as far as I can tell, the MainWindowController has released all of its contents and daOutline is nil (bad).
How do I get XCode to bring / reload the completed outline (or never release it) and get daOutline to a non nil state?
For those who come after there appeared to be two problems that led to the NSOutline outlet becoming nil. The first one was that in implementing the delegate protocol "shareInfoDelegate" I was creating a new instance of the MainWindowController, not the one with the data in it. This new instance did NOT have the IBOutlets connected (or much of anything useful about it).
Once I scrapped the Delegate and moved to using NSNotification to update information about the NSView textFields my NSOutline came "back".
The second, more minor, problem was that in the NSView nib file I placed and NSBox to mimic the behavior of a group row (e.g. a gray background). As a side effect the NSBox was inhibiting the normal row select behavior of the outline. Which made it very hard to determine which row was selected. When I deleted the NSBox, row selection became much more easy to determine.
in particular this Question and the answer by Chuck were helpful in sniffing this out.
Why is my NSOutlineView datasource nil?
Thanks Indeed(!)
I have the following code written in SWIFT for OS X App, the code is working fine (NSComboBox are select able only, not editable)
I have these two IBOutlet projNewProjType and projNewRouter, when I change the the selection of either of the NSComboBox, I can see the correct selected Index value and String value but how to check that the returned Index value is from projNewProjType NOT projNewRouter in the comboBoxSelectionDidChange()
import Cocoa
class NewProjectSetup: NSViewController, NSComboBoxDelegate {
let comboxProjValue: [String] = [“No”,”Yes”]
let comboxRouterValue: [String] = ["No","Yes"]
#IBOutlet weak var projNewProjType: NSComboBox!
#IBOutlet weak var projNewRouter: NSComboBox!
#IBAction func btnAddNewProject(sender: AnyObject) {
print(“Add New Button Pressed!”)
}
#IBAction func btnCancel(sender: AnyObject) {
self.dismissViewController(self)
}
override func viewDidLoad() {
super.viewDidLoad()
addComboxValue(comboxProjValue,projNewProjType)
addComboxValue(comboxRouterValue,projNewRouter)
self.projNewProjType.selectItemAtIndex(0)
self.projNewRouter.selectItemAtIndex(0)
self.projNewProjType.delegate = self
self.projNewRouter.delegate = self
}
func comboBoxSelectionDidChange(notification: NSNotification) {
let comboBox: NSComboBox = (notification.object as? NSComboBox)!
print("comboBox comboBox: \(comboBox)")
/* This printed “<NSComboBox: 0x6000001e1a00>”*/
print("comboBox objectValueOfSelectedItem: \(comboBox.objectValueOfSelectedItem)")
/* This printed the correct selected String value */
print("comboBox indexOfSelectedItem: \(comboBox.indexOfSelectedItem)")
/* This printed the correct selected Index value */
}
/* Add value to Combo box */
func addComboxValue(myVal:[String],myObj:AnyObject){
let myValno: Int = myVal.count
for i in 0..<myValno{
myObj.addItemWithObjectValue(myVal[i])
}
}
}
You already know the addresses of your two NSComboBox outlets and you know the address of which NSComboBox caused that notification to trigger, so why not do something like:
func comboBoxSelectionDidChange(notification: NSNotification) {
let comboBox: NSComboBox = (notification.object as? NSComboBox)!
if comboBox == self.projNewProjType
{
print("selection changed via self.projNewProjType")
}
if comboBox == self.projNewRouter
{
print("selection changed via self.projNewRouter")
}
You can set identifiers to your NSComboBoxes in IB. Select your combo box and choose identity inspector and name identifier. Then you are able to do like this:
if comboBox.identifier == "someIdentifier" {
// Do something
}
I have a custom popup view that has a UIDatePicker. This, when changed, changes the date of the save time. I also want the label on the in the CustomCell to be updated if the date has changed. I have used a delegate protocol to update the table but I cannot get this protocol to transfer the information on save. Can you help? I think I have hooked up all the correct code in the viewController class. I have tried this answer but I cannot set the delegate in the target class and there isn't a segue A Swift example of Custom Views for Data Input (custom in-app keyboard)
protocol DatePopUpViewDelegate: class {
func pastDate(date: String) // date that is chosen in picker
func isPastDateSet(isSet: Bool) // has chosen new date
}
#IBDesignable class DatePopUpView: UIView {
var delegate: DatePopUpViewDelegate?
func loadViewFromNib() -> UIView {
let bundle = NSBundle(forClass: self.dynamicType)
let nib = UINib(nibName: "DatePopUp", bundle: bundle)
let view = nib.instantiateWithOwner(self, options: nil)[0] as! UIView
delegate?.isPastDateSet(false)
return view
}
// close popup
#IBAction func closeButtonDatePopUp(sender: AnyObject) {
if dateToSave != openTime {
if let dateToSave = dateToSave {
SaveData.changedSaveTime = dateToSave
delegate?.pastDate(dateToSave)
delegate?.isPastDateSet(true)
}
} else {
SaveData.changedSaveTime = ""
delegate?.isPastDateSet(false)
}
}
class SaveTableViewCell: UITableViewCell, DatePopUpViewDelegate {
var changeDateLabel: Bool = false
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
changeDateLabel = false
datePopUpViewControllert.delegate = self
}
// delegate functions
func pastDate(date: String) {
self.labelDate = date
print("del date \(date)")
}
func isPastDateSet(isSet: Bool) {
self.changeDateLabel = isSet
print("is set by delegate \(isSet)")
}