Running into a really weird issue and couldn't find how to fix it. I have tab bar controller based app with 3 view controllers (2 table view controllers and one regular vc), they are Profile, Orders, People. When I sign in, I land on profile and the buttons in the nav bar show properly. As soon as I go to People and come back, the buttons disappear and don't show anymore. Also vice versa is true (going from People to Profile).
This is the additional weird part: if I go from profile to orders, then back, it will show all buttons. Also if I go from profile to orders to people, people shows normally.
Here is the structure:
In all viewDidLoad and viewWillAppear, I add the following code:
let editButton = UIButton()
editButton.frame = CGRectMake(0, 0, 60, 35)
editButton.setTitle("Edit Profile ", forState: .Normal)
editButton.setTitleColor(UIColor.blueColor(), forState: .Normal)
editButton.addTarget(self, action: Selector("editButtonPressed"), forControlEvents: .TouchUpInside)
let leftBarButton = UIBarButtonItem()
leftBarButton.customView = editButton
self.tabBarController?.navigationItem.leftBarButtonItem = leftBarButton
and in the viewWillDisappear, I add:
self.tabBarController?.navigationItem.leftBarButtonItem = nil
self.tabBarController?.navigationItem.rightBarButtonItem = nil
All except Orders table view controller doesn't have any of the above code. What is going on? I will be happy to provide more if needed, but this is really all there is to it as far as I understand.
You can try this:
1.Show:
self.navigationItem.rightBarButtonItem?.customView?.alpha = 1.0
2.hide:
self.navigationItem.rightBarButtonItem?.customView?.alpha = 0.0
Related
I know that you can set the title of the back button from the IB or in prepareForSegue, but in my app I need to update the title according to events that can happen while the controller is visible.
I tried but nothing happens:
self.navigationItem.backBarButtonItem = UIBarButtonItem(title: title, style: .Plain, target: nil, action: nil)
This works though but has no back arrow:
self.navigationItem.leftBarButtonItem = UIBarButtonItem(title: title, style: .Plain, target: nil, action: "popVC")
Any ideas?
The backBarButtonItem is the item used for the back button of the next controller in the navigation stack.
So for example if you have a navigation controller with a root viewController A and you push a viewController B, then the back button title that you see once B is pushed is configured using A.
You could have something like this :
A.navigationItem.backBarButtonItem = UIBarButtonItem(title: "Go back to A", style: .Plain, target: nil, action: nil)
Once B is pushed, you see a back button with "Go back to A".
In your case the tricky part is to find A in the navigation stack from B.
You can do it by searching in the viewControllers of the navigationController like so :
// This code works from the `B` view controller
let viewControllers = self.navigationController?.viewControllers ?? []
if let indexOfCurrent = viewControllers.indexOf(self) where (indexOfCurrent > viewControllers.startIndex) {
let indexOfPrevious = indexOfCurrent.advancedBy(-1)
let previousViewController = viewControllers[indexOfPrevious]
previousViewController.navigationItem.backBarButtonItem?.title = "New Title"
}
Edit
I don't know any clean way to refresh the navigation bar after that. Maybe you could ask a separate question just for that.
What you could do is pop and push the view controller without animation
if let navigationController = self.navigationController {
navigationController.popViewControllerAnimated(false)
navigationController.pushViewController(self, animated: false)
}
Or maybe try to create a new UIBarButtonItem instead of changing the title of the existing one.
try this:
let baritems = self.navigationController?.navigationBar.items
for item in baritems!{
if (item.leftBarButtonItem != nil){
item.title = "123"
}
}
This question is pretty old now, but I was a problem changing the back button text based on a nested tableViewController's selected cell.
It looks like the default back button for a navigationViewController bases its text on the title of the view controller it takes the user back to.
You should probably be careful, as my solution makes a couple assumptions that I'm not positive will always be true.
let vcs = navigationController?.viewControllers
vcs?[(vcs?.count)! - 2].navigationItem.title = "Your Text Here"
Assuming that our current view controller is at the top of the navigation stack -> vcs[vcs.count - 1]; there exists a view controller on that stack before this one -> vcs[vcs.count - 2]; and the navigationItem.title of that preceding view controller can be changed without unwanted side effects; we can change our back button text by changing the navigation title of that preceding view controller.
I have been looking and trying to solve an issue I have with a UIWebView for iOS.
I have a very small app which just loads my website the source code lives at https://github.com/pjuu/iotter.
On the site when a user clicks on a posted image it load the image URL in to the web view. This leaves them stranded and unable to get back to other parts of the site.
What I want to do is display an (x) button in the top right hand corner (no matter what screen rotation is in use) and have perform the back operation in the browser.
I know this question isn't a code issue as I'm fine to sort of the Swift code part of it. I just could not for the life of me work out how to add the button programmatically and have it display over the webview.
The only tutorials I could find involved creating a tool bar to perform these type of actions which I think would take up to much space when looking at an image.
The question is very simple:
Is this possible?
If so how would I go about creating the button?
I am going to check the request.path parameter with regex to only show it if it matches an image URL.
Apologies if this isn't fitting enough for SO. I am happy to move the question or post on another site.
Thank you for any help in advance. I am not a mobile developer so using XCode and the storyboard stuff is a world away from vim for me.
REFERENCE:
1) CGRectMake: https://developer.apple.com/library/ios/documentation/GraphicsImaging/Reference/CGGeometry/#//apple_ref/c/func/CGRectMake
2) UIWebViewDelegate:
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIWebViewDelegate_Protocol/#//apple_ref/occ/intfm/UIWebViewDelegate/webView:shouldStartLoadWithRequest:navigationType:
SOLUTION:
1) Create the "X" UIButton:
// Define the UIButton
let button = UIButton(type: UIButtonType.System) as UIButton
let image = UIImage(named: "name") as UIImage?
button.frame = CGRectMake(self.view.frame.width - 60, 30, 35, 35)
button.setTitle("Test Button", forState: UIControlState.Normal)
button.setImage(image, forState: .Normal)
button.addTarget(self, action: "buttonAction:", forControlEvents: UIControlEvents.TouchUpInside)
self.view.addSubview(button)
//Hide the UIButton
button.hidden = true
2) Detect when an imageUrl is opened and make the "X" UIButton appear:
// This function is triggered every time a request is made:
optional func webView(webView: UIWebView, shouldStartLoadWithRequest request: NSURLRequest, navigationType: UIWebViewNavigationType) -> Bool {
let string = request.URL
if string.rangeOfString(".png") || string.rangeOfString(".jpg")|| string.rangeOfString(".jpeg"){
// code to make cross appear
// for example:
self.button.hidden = false
}
}
3) Finally, you will need to create the method that closes the page when the "X" UIButton is tapped:
func btnPressed(sender: UIButton!) {
if(webview.canGoBack) {
//Go back in webview history
webview.goBack()
} else {
//Pop view controller to preview view controller
self.navigationController?.popViewControllerAnimated(true)
}
}
N.B.:
In the lines:
let image = UIImage(named: "cross.png") as UIImage?
button.setImage(image, forState: .Normal)
We are setting the UIButton to be the image of a cross.
You need to add a cross image to your XCode project and set the "cross.png" String to the exact name of your image: "nameOfImage.fileType".
Simple one line solution.
Create a desired "close" button in storyboard, or programmatically.
Then, just send your WebView to the back of all current views displayed in your view controller:
view.sendSubviewToBack(yourWebView)
Now, all views (including any buttons you create) will be displayed on top if it. Just be sure to add this line after all of your desired views are created.
I have a navigation bar placed directly on my scene. On his I have a navigation item. I can successfully change title on it.
Now I want a back button to appear - I do not need any customization at present, just the ability to catch the click and default ios look for whatever plaform the app is running (Since Swift that is ios7+).
In viewDidLoad() I have written
outletCatalogNavItem.backBarButtonItem = UIBarButtonItem(title: "test", style .plain, target: self, action: "ownbackNavigationFuncCode");
In *ViewDidAppear()* outletCatalogNavItem.backBarButtonItem is non-nil
Note: I am not using any shared navigation control across scenes in my storyboard - nor wish to at this point since I am porting an app from another tool/language which has its own navigation/stack logic already (meaning I handle switching and navigation myself in code)
Embed your view controller in a UINavigationController. When you push/segue to a new view controller the < Back button you're looking for will appear on the left hand-side.
let backItem = UIBarButtonItem()
backItem.title = "Back"
navigationItem.backBarButtonItem = backItem
I'm writing a to-do list type app, in order to learn swift for iOS development. I had a settings button on the Navigation bar, on the right side, and whenever a person clicked a button on top of the table view, they could add a new item to their list. That causes a "cancel" button to appear on the left side of the bar and a "add" button to appear on the right side. When the person is done, however, those buttons disappear, and so I programatically re-create the settings button, with a call to a function that is supposed to call the segue.
self.navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "modify"), style: UIBarButtonItemStyle.Plain, target: nil, action: Selector("showSettings:"))
This is the code that creates the button on the navbar (and it is indeed created)
func showSettings(sender: AnyObject?) {
print("segueShouldBeDone!")
performSegueWithIdentifier("showSettings", sender: sender)
}
And this is the function that is supposed to call the segue (I added the print to see if it was at least being called, and it isn't).
I've had this same problem in another place in my code, but I had given up on fixing it cause it wasn't that important for me then. But now it is interfering with how the app works, so I wanted to know how to fix it.
Any help would be great.
Your showSettings: selector isn't being called because you specified nil instead of self for the bar button item's target. Change the line to:
self.navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "modify"), style: UIBarButtonItemStyle.Plain, target: self, action: Selector("showSettings:"))
This assume the showSettings: method is in the same class that contains this line of code.
Read the documentation for this initializer, specifically the info about the target parameter.
I have a settings bar button item (set as left bar button item). I only want to display it if the user is logged in.
I thought I could use the following for anonymous users
navigationItem.leftBarButtonItem = nil
But then how would I show it as soon as they logged in?
You can store a copy of the leftBarButtonItem in a strong property and update it after the users log in.
var leftBarButtonItem : UIBarButtonItem!
Inside viewDidLoad:
self.leftBarButtonItem = UIBarButtonItem(title: "test", style: UIBarButtonItem.Style.Plain, target: nil, action: nil)
In logic:
if loggedIn
{
self.navigationItem.leftBarButtonItem = self.leftBarButtonItem
}
else
{
self.navigationItem.leftBarButtonItem = nil
}
Best Way is just custom your Bar buttom with image. Set barbuttom.image = nil to Hide again assign the image to show. And dont forget to make the barbutton isEnabled as false.
I have more that 2 menuitems and remove/add menuitem is an overhead. This code snippet worked for me.
func showMenuItem(){
menuItemQuit.customView?.isHidden = false
menuItemQuit.plainView.isHidden = false
}
func hideMenuItem(){
menuItemQuit.customView?.isHidden = true
menuItemQuit.plainView.isHidden = true
}
if you want to hide/show UIBarButtonItem : For Swift 3
Used below simple code :
Declaration :
var doneButton = UIBarButtonItem()
In ViewDidLoad() or ViewWillAppear() or where you want to hide it : [hide bar button]
self.navigationItem.rightBarButtonItem = nil
where you want to show bar button : [use anywhere in your code]
self.navigationItem.rightBarButtonItem = self.doneButton
doneButton = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.plain, target: self, action: #selector(YourViewController.dismissPicker))
Swift 5.x
I faced the same dilemma and unfortunately no solution worked for me. Adding and removing buttons and related segues is unnecessarily too much of code when it includes multiple buttons on multiple screens. I have taken this approach for one or two buttons in the past and it becomes pretty ugly pretty fast.
The code menuItemQuit.customView?.isHidden = false doesn't seem to work on iOS 13 and above either, otherwise it would have made life so much easier.
My approach was to simply disable the bar button and change its tint to the navigation colour's tint.
In my app What.To.Eat I display bar buttons based on user's login status. Every element of the app is themed so that I could control all the colors based on various factors.
The navigation bar's color is named commonButtonColor and the bar buttons tint color is named commonButtonColor.
When I have to hide a bar button, I simply do the following:
let nav = self.navigationController?.navigationBar
nav?.tintColor = Theme.shared.titleText
nav?.barTintColor = Theme.shared.headerBg
if person.loggedIn {
mealPrefsBarButton.tintColor = Theme.shared.commonButtonColor
mealPrefsButton.isEnabled = true
} else {
mealPrefsBarButton.tintColor = Theme.shared.headerBg
mealPrefsButton.isEnabled = false
}
Where theme colors are defined in a separate file like this:
static var headerBg: UIColor {
return UIColor(red: 0.965, green: 0.969, blue: 0.973, alpha: 1.00)
}
The above is a simplified version of what I do in the app to make it clear what I am doing. I hope it would help someone trying to achieve the same. It is simple solution and works just perfectly with a few lines of code.
As an example from the app, this is how two buttons appear and disappear based on whether the My Recipes button is selected or not:
I have a same problem and solved. I have a bar button item with image
barbtnClose.isEnabled = false
barbtnClose.image = nil
barbtnClose.customView?.isHidden = true // do not work in iOS 13
Swift 5
A better solution and works even if you have set a custom navigation bar.
Hide navigation bar button item or back button leftBarButtonItem / rightBarButtonItem
if login == true {
self.navigationItem.leftBarButtonItem = nil
} else {
print("set your bar button or return")
}
Hide back bar button in navigation controller with swift 5
self.navigationItem.leftBarButtonItem = nil
self.navigationItem.hidesBackButton = true