I am trying to do something this:
I want to pass some data to ApplicationsViewController which is embedded in nav bar, therefore I get the error: Could not cast value of type 'UINavigationController'
I am not able to understand how to implement the same. Help is much appreciated. Thank you.
The reason is you can't pass data directly to ApplicationViewController as InboxViewController segue's destination is UINavigationController.
So, first you need to access UINavigationController and after that ApplicationsViewController from the stack.
Try the code below:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "goToApplications" {
if let navigation = segue.destination as? UINavigationController, let applicationVC = navigation.topViewController as? ApplicationsViewController {
applicationVC.id = "RGB"
}
}
}
when pass data application view controller which is rootviewController of UINavigationController. you should give segue name of navigation controler and type cast as UINavigationController as destination viewcontroller.
Fetch rootviewController which is application View controller and assign value of id
Here is code how to assign value to Application ViewController
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
if segue.identifier == "navigationSegue" { // segue of navigationVC
let navVc = segue.destination as! UINavigationController
let appVc = navVc.viewControllers.first as! ApplicationsViewController
appvc.id = "RGB"
}
}
Related
I want to pass data from ViewController1 to ViewController2. ViewController2 is embedded within a Navigation Controller (because I have a Segmented Control that corresponds to 3 Child View Controllers). My segue is directly from ViewController1 to the Navigation Controller.
I tried the following in ViewController1:
ViewController2().testID = "test value"
With the following in ViewController2:
var testID = ""
However testID does not update when I run print(testID) in ViewController2.
What is recommended for passing data from ViewController1 to ViewController2? Any help/advice is much appreciated!
You can pass the value by overriding the prepare(for segue:) function in ViewController1
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destination
guard let destination = segue.destination as? UINavigationController else {
return
}
guard let finalDestination = destination.viewControllers.first as? ViewController2 else {
return
}
finalDestination.testID = "Test Value"
}
NSUserDefaults will always work.
I'm trying to segue from one view controller to another, and pass data to the next controller. But I keep getting this error:
Could not cast value of type 'UITableViewController' to 'UINavigationController'
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if (segue.identifier == "segueLogWaterData") {
// pass data to next view
let nav = segue.destinationViewController as! UINavigationController
let segueViewController = nav.topViewController as! WaterDataViewController
}
}
This happens with WaterDataViewController as a UITableViewController. I've also tried embedding WaterDataViewController into a UINavigationController but I get a similar error:
Could not cast value of type 'UITableViewController' to 'MyApp.WaterDataViewController'
What am I doing wrong?
Actually, the segue.destinationViewController isn't the navigation controller; rather, it is the view controller that the segue is opening. Since UITableViewController is a subclass of UIViewController, this code should work just fine:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if (segue.identifier == "segueLogWaterData") {
let dest = segue.destinationViewController as! WaterDataViewController
//Assign to dest's properties
}
}
nav.topViewController is a UITableViewController. Apparently, WaterDataViewController is not a subclass of UITableViewController.
Do you mean to be using rootViewController instead?
I get the same error sometimes because of "omitting class" to my view controller in the storyboard.
I have to write an iOS app that supports both iOS 7 and 8 and in this app I have two view controllers A and B with navigation controllers and a segue between them. When the segue activates, I have to fetch data from the view controller A to the view controller B. My code works perfectly on iOS 8 but not on iOS 7.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
if segue.identifier == userDataSegue {
let navController = segue.destinationViewController as? UINavigationController
if let userDataTableViewController = navController?.topViewController as? UserDataTableViewController {
userDataTableViewController.userData = user
}
}
}
Do you know why does this happen and how can I fix it? I could "work around" the problem by saving stuff in NSUserDefaults and reading it in the vc B but that would make my code a mess.
I appreciate any help :D
Don't forget to create a public property userData in Second ViewController.
override func prepareForSegue(segue: UIStoryboardSegue!, sender: AnyObject!)
{
if (segue.identifier == "segueTest") {
var svc = segue!.destinationViewController as secondViewController;
svc.userData = user
}
}
Hi I have 4 view Controllers
MainVC ----> NavBar ----> MyViewController----->UIWebView
Inside my MainVC based on segue, I want to set different data to tableview controller. Here is my prepareforsegue method
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
var navController = segue.destinationViewController as UINavigationController
var HVController = navigationController?.viewControllers[0] as MyViewController
HVController.somevar = "Something"
}
However program crashes. How can I pass data from my MainVC to MyViewController? Thanks.
EDIT: I have found my stupid mistake the code should have been as
var HVController = navController.viewControllers[0] as MyViewController
Sorry for wasting your time.
First you have to add a variable in your Target ViewController (MyViewController).
For example:
var passValue:String!
Then, you can pass value from your current ViewController to the target:
if segue.identifier == "yourSegueIdentifier" {
(segue.destinationViewController as MyViewController).passValue = yourObjectToPass
}
I am working on a custom camera app where I present 3 viewControllers modally. At each segue, I pass data with prepareForSegue function. My problem is after the work with camera is finished, I need to show 2 more viewControllers which need to be inside a navigationController.
I have realized that If I don't pass any data, the navigation controller works fine. However, when I pass data, the app crashes on runtime. What is the right way of doing this?
Here is my prepare for segue function;
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "camera2Crop"{
let controller: CropViewController = segue.destinationViewController as CropViewController
controller.photoTaken = self.photoTaken
}
}
where photoTakenis an UIImage object. Moreover, here is the screenshot from my storyboard where I put the navigationController. I call the prepareForSeguefunction in CustomCameraViewController to segue to CropViewController.
EDIT: I have changed my prepareForSegue to the following code;
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "camera2Crop" {
let controller: CustomNavigationController = segue.destinationViewController as CustomNavigationController
controller.photoTaken = self.photoTaken
}
}
Now the app does not crash but I don't know how to send an object through Navigation Controller
let controller: CropViewController = segue.destinationViewController as CropViewController
Double check if segue.destinationViewController is actually the navigation view controller.
If it's the navigation controller, get CropViewController from it:
if segue.identifier == "camera2Crop" {
let navController = segue.destinationViewController as UINavigationController
let controller = navController.viewControllers[0] as CropViewController
controller.photoTaken = self.photoTaken
}
Note you don't have to subclass UINavigationController.