I'm new to swift. My app uses photos people upload to the web and showing the photos in a table view.
It is reloading whenever some user uploads a new photo.
I have a UITextField that when you press it the keyboard goes up. My problem is that it goes down whenever reloadView is happening (when a new photo arrives)
What i'm trying to do is to check if the UITextField is first recogniser and if so I want to wait with the reload until it not first recogniser.
func refreshView()
{
dispatch_async(dispatch_get_main_queue()) { () -> Void in
while (self.dataSource.writeSomethingTextLabel.isFirstResponder()) {
//need to wait somehow for notification that it is not first responder anymore
}
self.tableView.reloadData()
}
}
So with this code the keyboard is not going down of course but the wile loop runs and everything is stuck. my question is how can I wait until the user finishes using the text label (first responder is false).
thanks
You can conditionally reload tableView on two places: when new data arrives and when textField ends editing:
#class YourViewController: UIViewController, UITextFieldDelegate {
var needsToReloadTableView = false;
func reloadTableViewIfNeeded() {
if needsToReloadTableView {
self.tableView.reloadData()
needsToReloadTableView = false
}
}
func gotNewData() {
needsToReloadTableView = true
if !self.textField.isFirstResponder {
reloadTableViewIfNeeded()
}
}
func textFieldDidEndEditing(textField:UITextField) {
reloadTableViewIfNeeded()
}
}
#IBAction func viewTapped(sender : AnyObject) {
totalTextField.resignFirstResponder()
}
Related
As you can see I'm having trouble formulating the question. Let me try to explain:
I'm using a search bar in my swift ios app. In order to get a desired animation effect I put it in a vertical stack view and then animate its isHidden property. This way search bar pushes down other children of the stack view as it animates in or pulls them up as it animates out. So far so good.
I've noticed a behavior that I think is strange. Could be a bug or could be me not understanding how things work. Basically if I call search bar hiding method x times in a row I need to call search bar showing method x times before it would show. I'd expect to have to make just one call to show search bar regardless of how many times I called hiding method. The issue doesn't exist other way around: if I call search bar showing code x times I only need to call hiding method once for it to go away. This doesn't happen if I set isHidden without animating it...
Here's a sample code and a video of the issue. I'd appreciate it if someone would help me understand this behavior.
class ViewController: UIViewController {
#IBOutlet weak var searchBar: UISearchBar! {
didSet {
searchBar.isHidden = true
}
}
#IBAction func showAction(_ sender: UIButton) {
expandSearch()
}
#IBAction func hideAction(_ sender: UIButton) {
collapseSearch()
}
private func expandSearch() {
UIView.animate(withDuration: 0.3){
self.searchBar.isHidden = false
}
}
private func collapseSearch() {
UIView.animate(withDuration: 0.3){
self.searchBar.isHidden = true
}
searchBar.resignFirstResponder()
}
}
You should not call an asynchronous animation of searchbar x times, instead of I suggest you to keep its state in variable, something like isSearchBarHidden,
and check it before show/hide search bar. You could use just one method with such signature showSearchBar(show: Bool) and setting this variable there.
#IBAction func showAction(_ sender: UIButton) {
showSearchBar(true)
}
#IBAction func hideAction(_ sender: UIButton) {
showSearchBar(false)
}
private
func showSearchBar(_ show: Bool) {
guard isSearchBarHidden != show else {
return
}
UIView.animate(withDuration: 0.3, animations: {
self.searchBar.isHidden = show
}) {
self.isSearchBarHidden = show
if !show && searchBar.isFerstResponder {
searchBar.resignFirstResponder
}
}
}
private
var isSearchBarHidden: Bool = true
Also it is a good practice to check if your textView/textField/searchBar isFirstResponder before call resignFirstResponder.
Hope it will help. Good luck!
i want to make 2 action for a button like that.
selected and deselected action for 1 button.
#IBAction func btntouch(sender: UIButton) {
if firsttouch
{
print bla bla
change button to selected style. maybe background color.
}
else
{
}
}
how can i do that?
In case you need to split two button statuses - like ON and OFF, try this:
var buttonSwitched : Bool = false
#IBAction func btntouch(sender: UIButton) {
//this line toggle your button status variable
//if true, it goes to false, and vice versa
self.buttonSwitched = !self.buttonSwitched
if self.buttonSwitched
{
//your UI styling
}
else
{
//your opposite UI styling
}
}
Create 2 IBActions:
#IBAction func touchDown(_ sender: AnyObject) {
print("down")
}
#IBAction func touchUp(_ sender: AnyObject) {
print("up")
}
When connecting the first one, make sure the event is set to touchDown. For the second one, make sure it is set to touchUpInside
Yes, you can. Depending on your requirements, you could store the current state of the button in the view controller or in the model.
If the visual change caused by the first touch needs to be persisted across opening and closing of your view controller, store the value indicating the change in the model; if you need to reset the visuals when the view controller shows, store the value in the view controller itself:
var firstTouch = true
#IBAction func btntouch(sender: UIButton) {
if firstTouch {
firstTouch = false
...
} else {
...
}
}
I wonder how I can show a VC after the remote data has loaded. I am not using a tableView but a normal VC.
My code look like this:
viewDidLoad:
override func viewDidLoad() {
super.viewDidLoad()
loadItemData(id)
}
func loadItemData(aId: Int) {
Service.getItem(aId) { (JSON) -> () in
self.iData = JSON
self.configureData(self.iData)
}
}
func configureData(iData: JSON) {
if let type = iData["item_type"].int {
if let == 1 {
someButton.hidden = true
}
}
if let title = iData["item_title"].string {
titleLabel.text = title
}
}
What happens is that my VC first loads with the button visible and with my text label containing "dummy text" from storyboard, then when the data has loaded the button will hide and the text label will change.
So my question now is how I can hide my VC or show some loading indicator until the data has loaded.
Also worth saying this is the 2nd view. My apps start with a tableView and when you click on a cell you end up in this VC. So I could also load the data when the cell gets clicked then pass it to this VC.
Using the activity indicator is better, here's how to do it
First make sure you add Activity Indicator in your VC
override func viewDidLoad() {
super.viewDidLoad()
self.myActivityIndicator.startAnimating()
loadItemData(id)
}
func loadItemData(aId: Int) {
Service.getItem(aId) { (JSON) -> () in
self.iData = JSON
self.configureData(self.iData)
self.myActivityIndicator.stopAnimating()
}
}
Rather than try to hide the VC (try to load the data and pass it), it will makes the apps feel not responsive, because you have to wait the data loaded and then the VC will show.
I got a iPad-designed app using a SplitViewController showing two views, one with a contacts list and another with details of this contact. The SplitView works well on iPad but has some problems on iPhones.
There is a UIControl that take all the size of the Master View, that check if there is any .touchDown interaction by the user and some methods called to enable or disable this UIControl depending if we are on editing contact mode or not allowing user to interact with the screen or not :
private var disableInteractionClosure: (()->())?
private lazy var interactionOverlay: UIControl = {
let c = UIControl()
c.autoresizingMask = [.FlexibleHeight, .FlexibleWidth]
c.addTarget(self, action: "interactionOverlayAction", forControlEvents: .TouchDown)
return c
}()
func disableInteractionWhileEditingWithClosure(callback: ()->()) {
if disableInteractionClosure == nil {
disableInteractionClosure = callback
/* display control overlay */
interactionOverlay.frame = navigationController!.view.bounds
navigationController!.view.addSubview(interactionOverlay)
}
}
func interactionOverlayAction() {
disableInteractionClosure!()
}
func enableInteraction() {
disableInteractionClosure = nil
interactionOverlay.removeFromSuperview()
}
Basically the UIControl is used to block user from switching between contact while user is editing another contact/ creating a new one by blocking interaction with the contact list and if changes have been made on the editing/creating view it fires a method that shows a pop up saying "modifications have been made do you want to continue without saving ? cancel or continue " :
func cancel() {
self.view.endEditing(true)
let closure: ()->() = {
self.layoutView.willResign()
self.delegate?.tabDetailsControllerDidCancel(self)
}
if layoutView.hasChanges() {
MKAlertViewController().instantaneousAlert(title: "Modification apportées", message: "Êtes-vous sur de vouloir continuer sans sauvegarder les modifications ?", confirmButtonTitle: "Oui", cancelButtonTitle: "Annuler", confirmed: { () -> Void in
closure()
}, canceled: { () -> Void in
})
} else {
closure()
}
}
It works fine on iPad because the UIControl is only above the Master View and is enabled when in editing mode on the Detail View (iPad 3D Debugging view), so the pop up shows only when manually cancelling the editing/creating or when trying to change contact while editing/creating, but as the splitView don't work the same on iPads and iPhones and it appears that on iPhone the Master View is placed above the Detail View, the UIControl is also above (iPhone 3D Debugging view), and it causes to block interactions on all the screen and wherever I click the cancel pop-up is shown.
Can you guys explain me a way to enable/show this UIControl only when the MasterView is showing and not everywhere. Thanks.
I ended up using the viewWillDisappear on the detail view :
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
if self.isMovingFromParentViewController() || self.isBeingDismissed() {
if editingMode {
shared.contactsListController.disableInteractionWhileEditingWithClosure({ (_) in
self.tabDetailsController.cancel()
})
shared.contactsListController.disableToolbar()
} else {
shared.contactsListController.enableInteraction()
shared.contactsListController.enableToolbar()
}
self.navigationController?.toolbar.alpha = 1
}
}
and modifying the disableInteractionWhileEditingWithClosure method on the master view:
func disableInteractionWhileEditingWithClosure(callback: ()->()) {
if disableInteractionClosure == nil {
disableInteractionClosure = callback
/* display control overlay */
interactionOverlay.frame = navigationController!.view.bounds
view.addSubview(interactionOverlay) // this line
}
}
and it works ! :)
In the following code I am trying to transfer control from UITextField to the next via a next button.
I am doing this by calling becomeFirstResponder on the next UITextField.
If I don't type anything in the first and current UITextField the next button works as expected. The keyboard stays up and the focus is transferred.
If I do type something, and only if the field is empty. The method becomeFirstResponder for the next field is called and returns true, yet the keyboard is dismissed and focus is not transferred.
public func numberPad(numberPad: APNumberPad, functionButtonAction:UIButton, textInput: UIResponder) {
var current:UITextField?
for field in editCells {
if (current != nil) {
field.valueTextField.becomeFirstResponder()
return;
}
if (field.valueTextField == activeField) {
current = field.valueTextField
}
}
textInput.resignFirstResponder()
}
This function is called when the NEXT or DONE button is pressed on the keyboard. Which is a custom number keypad. APNumberPad specifically.
https://github.com/podkovyrin/APNumberPad
It is my delegate function.
Anyone know any reason becomeFirstResponder would return true and not work, only in some cases, but work in others?
And yes this is the main UI thread. Adding a call to resignFirstResponder on the current field, then a delay and calling becomeFirstResponder works. This causes the keypad to flicker, no matter how small the delay though.
Edit... I am now doing this... and am living with the keyboard flicker for now:
Delay is a helper function for GCD
public func numberPad(numberPad: APNumberPad, functionButtonAction:UIButton, textInput: UIResponder) {
var current:UITextField?
for field in editCells {
if (current != nil) {
current?.resignFirstResponder()
delay (0) {
field.valueTextField.becomeFirstResponder()
}
return;
}
if (field.valueTextField == activeField) {
current = field.valueTextField
}
}
textInput.resignFirstResponder()
}
I don't know if it helps you, or not. I wrote a simple UITextField extension that contains a returnView variable which decides what the textfield should do on return key press:
turn to next text field (if the returnView is an UITextField)
simulate button touch (if the returnView is a UIButton)
or hide keyboard
class NextTextField: UITextField, UITextFieldDelegate {
#IBOutlet weak var returnView: UIView? {
didSet {
if returnView is UITextField {
returnKeyType = UIReturnKeyType.Next
}
}
}
override func awakeFromNib() {
super.awakeFromNib()
delegate = self
}
func textFieldShouldReturn(textField: UITextField) -> Bool {
if let nextTextField = self.returnView as? UITextField {
nextTextField.becomeFirstResponder()
} else if let nextButton = self.returnView as? UIButton {
nextButton.sendActionsForControlEvents(.TouchUpInside)
} else {
self.resignFirstResponder()
}
return true
}
}