i've been struggling with for sometime. I'm trying to present a viewController modally, but everytime i do this i get following error:
libswiftCore.dylib`swift_dynamicCastClassUnconditional:
0x10f7d57d0: pushq %rbp
0x10f7d57d1: movq %rsp, %rbp
0x10f7d57d4: testq %rdi, %rdi
0x10f7d57d7: je 0x10f7d580e ; swift_dynamicCastClassUnconditional + 62
0x10f7d57d9: movabsq $-0x7fffffffffffffff, %rax
0x10f7d57e3: testq %rax, %rdi
0x10f7d57e6: jne 0x10f7d580e ; swift_dynamicCastClassUnconditional + 62
0x10f7d57e8: movq 0xae741(%rip), %rax ; swift::ISAMask
0x10f7d57ef: andq (%rdi), %rax
0x10f7d57f2: nopw %cs:(%rax,%rax)
0x10f7d5800: cmpq %rsi, %rax
0x10f7d5803: je 0x10f7d581d ; swift_dynamicCastClassUnconditional + 77
0x10f7d5805: movq 0x8(%rax), %rax
0x10f7d5809: testq %rax, %rax
0x10f7d580c: jne 0x10f7d5800 ; swift_dynamicCastClassUnconditional + 48
0x10f7d580e: leaq 0x332fd(%rip), %rax ; "Swift dynamic cast failed"
0x10f7d5815: movq %rax, 0xae5cc(%rip) ; gCRAnnotations + 8
0x10f7d581c: int3
0x10f7d581d: movq %rdi, %rax
0x10f7d5820: popq %rbp
0x10f7d5821: retq
0x10f7d5822: nopw %cs:(%rax,%rax)
Which is on following line:
let showItemVc = showItemStoryboard.instantiateViewControllerWithIdentifier("ShowItemViewController") as ShowItemViewController
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
if segmentedControl?.selectedSegmentIndex == 0 {
let showItemStoryboard = UIStoryboard(name: "ShowItemStoryboard", bundle: nil)
let showItemVc = showItemStoryboard.instantiateViewControllerWithIdentifier("ShowItemViewController") as ShowItemViewController
self.presentViewController(showItemVc, animated: true, completion: nil)
}
}
It works if i just change
as ShowItemViewController
to
as UIViewController
But then i cant push values to the ShowItemViewController, what is the issue here?
import UIKit
class ShowItemViewController: UIViewController, UITableViewDelegate {
@IBOutlet var pageControl: UIPageControl?
@IBOutlet var tableView:UITableView?
var userId: NSString?
var itemId: NSString?
override func viewDidLoad() {
super.viewDidLoad()
var no = (UIBarButtonItem(title: "Cancel", style: UIBarButtonItemStyle.Plain, target: self, action: Selector("itemCancel:")))
self.navigationItem.leftBarButtonItem = no
var hiddenButton = (UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.Add, target: nil, action: nil))
self.navigationItem.rightBarButtonItem = hiddenButton
println(userId)
self.tableView?.registerNib(UINib(nibName: "ImagePageViewCell", bundle: nil), forCellReuseIdentifier: "ImagePageViewCell")
pageControl = UIPageControl()
pageControl?.frame = CGRectZero
pageControl?.currentPage = 0
pageControl?.numberOfPages = 3
pageControl?.tintColor = UIColor.whiteColor()
pageControl?.userInteractionEnabled = false
self.navigationItem.titleView = pageControl?
}
}
If you're instantiating a UINavigationController
that has your ShowItemViewController
inside it, you need a reference to that view controller. UINavigationController
has a topViewController
property that represents the first child item that's added to it. This is the item you need if you want to populate data in the ShowItemViewController
, and it's embedded in a navigation controller.
let showItemStoryboard = UIStoryboard(name: "ShowItemStoryboard", bundle: nil)
let showItemNavController = showItemStoryboard.instantiateViewControllerWithIdentifier("ShowItemViewController") as UINavigationController
let showItemVC = showItemNavController.topViewController as ShowItemViewController
// Set the properties in your showItemVC
presentViewController(showItemNavController, animated: true, completion: nil)
You should also check that the let
s are actually successful by doing the if let XXX = YYY as? ZZZ {}
if let XXX = YYY as? ZZZ {}
dance before proceeding, or you'll get a runtime error.
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