We have created a segue from a UITableViewCell in scene A to show scene B. How can you see that relationship in Xcode?
In Xcode we can select the source scene, look at Utilities \ Connections Inspector and see the segue. The storyboard shows the link between scene A and B. But I can't see how you can determine that the UITableViewCell in scene A is the UI element which triggers the segue.
The segue is not hooked up automatically to your table view by creating it in the Storyboard. A segue is just information that says we can transition from view A to view B. You've got to manually kick it off in tableView:didSelectRowAtIndexPath: with a call to performSequeWithIdentifier:, passing in the value you've set for the Identifier field for the segue in your Storyboard.
If you select the segue in the outline view you can see the linkage:
The outline view is shown with by clicking this image in the bottom left corner of the storyboard editor:
Related
I created a new Xib file, called MainViewController.xib. I dragged a View onto the builder, then plopped a UIButton on top of the view. Nothing happened, my button is on the view but not considered a subview. There is no hierarchy tree on the left column under the View icon that tells me my button is a subview.
Why is that? Every time I control+drag from the button to the view icon, the information for constraints pops up, instead of anything regarding an IBOutlet connection.
I'm using Xcode 7.1.2
I can control+drag to from my button to my .h file and create a property, but other than that, it's not recognized as a subview. Any help at all will be appreciated, I'm losing my mind.
In Xcode 7.3, when I drag in a Table View from the Object Library to the Storyboard for a single view app, it doesn't automatically expand to the full size of the view. I seen it do that in my Udacity class videos and in other videos on YouTube. Is there a setting in Xcode that will correct this? Thanks.
Yes, you need to "pin" the tableView at the ViewController. Am I right you have a simple ViewController and add a tableView to it?
Now, you need to open the Pin Menu and uncheck the checkbox "Constrains to margins". Now you add the constrains to the top, left, right and bottom to 0 and save it. Now the TableView should stretch the whole display.
If you only show a table in the ViewController you should use a UITableViewController.
I have created a view and the content is larger than the screen. How do I add this view as a subview of a scrollview? For some reason I can't do this in Document Outline. It will only let me add the scrollview as a subview of the existing view.
Select your view in Interfacebuilder and then use the menu command Editor:Embed In:Scroll View
I can't get the standard back button of iOS into a navigationBar because I can't find it in the Object Library, so can I do it with code or something else?
I just want the normal, standard, blue back button - you know which I mean.
To "automatically" have a back button you need first have a UINavigationController. Then you need to take a different UIViewController and add it as the root view controller in UINavigationController's init method:
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:someOtherViewController];
Be sure to also set a title for someOtherViewController, usually in it's viewDidLoad or initializer. I'll tell you why this is important in a second:
self.title = #"Some other VC";
Then take a second UIViewController and push it onto your navigation controller:
[navigationController pushViewController:anotherViewController animated:YES];
You now have two UIViewControllers on your navigation stack: someOtherViewController and anotherViewController.
Your view will now have a back button with "Some other VC" in it. This is the title of the view controller that was just moved out of view:
http://developer.apple.com/library/ios/#documentation/uikit/reference/UINavigationController_Class/Reference/Reference.html
http://simplecode.me/2011/09/04/an-introduction-to-uinavigationcontroller/
I would also suggest reading up on how UINavigationControllers work and searching this site a bit more for customizing the back button. There are plenty of threads about it.
You can't add the back button yourself. The back button is part of the Navigation controller. If you embed a Navigation controller into your view(s), the back button will appear and be populated by the name of the previous view.
If you're using storyboards select your view controller, then in top menu choose "editor" -> "embed in" -> "navigation controller".
Edit: Here is an exmaple.
I'm running Xcode 7.2. This was driving me crazy, but I figured it out. Here are all the pieces you need to make the Back button appear (make a test project to prove it):
1) You have to have a Navigation Controller and it has to be set to be the initial view controller. So add the Navigation Controller, you will import two tables. Click on the Navigation Controller and on the properties list, check the box that reads "Is Initial View Controller". You will now see and arrow pointing to this view.
2) In our case we want a ViewController and not the included / connected TableViewController, so delete the TableViewController (RootController) and add a new ViewController.
3) Connect the Navigation Controller to the new ViewController by clicking on the top bar of the Navigation controller and orange circle with the arrow pointing left. Hold the Control button on your keyboard down and click and drag from the orange circle to the ViewController and let go. When given the list of options on how to connect the two views, select 'root view controller'.
Done! Now you the functioning navigation bar and you automatically get the back arrow on all segues added. Test this. Add another ViewController and connect to it with a button on the existing ViewController. Use the Control-click-drag approach from the button to the newest ViewController. Select the 'show' option for the new segue you created.
Run it. You'll see the back option has automatically appeared when you click the button and moved to the newest ViewController.
This is all provided by the Navigation Controller, but only when you make another controller the RootController. Happy navigating!
i am working on storyboards which has couple of views on first view a condition is placed i want if the condition satisfies then only navigation should happen
For this i have used Custom segue but no matter my condition satisfies or not it navigates to new view.
I have created method in custom segue class
- (void) perform{
NSLog(#"source %#",self.sourceViewController);
NSLog(#"dest %#",self.destinationViewController);
UIViewController *sVC=self.sourceViewController;
UIViewController *dVC=self.destinationViewController;
[sVC.navigationController pushViewController:dVC animated:YES];
}
I want to set condition if result is 1 then only it should navigate. Woul prepareforsegue or initwithsegue provide me any help
Are you saying that you only want to perform the segue if a condition is true?
If so, instead of creating the segue directly from a control or table cell, create a triggerless segue. A triggerless segue has the view controller as its source, and it won't ever fire automatically. Instead you can fire it programmatically any time you like, including from an IBAction.
To create a triggerless segue, start control+dragging the segue from the containing view controller icon in the scene dock at the bottom of the scene. Drag to the destination scene like normal, and pick the segue type. Select the segue, and in the inspector, choose a segue identifier.
At runtime, when you want to perform the segue, invoke -[UIViewController performSegueWithIdentifier:sender:]. You can pass any object you'd like for the sender, including nil. If the sender has no use to you, pass nil.
So, in summary:
Create a triggerless segue from the view controller to the destination scene
Set an identifier for the segue in the inspector
At runtime, and form code, call -[UIViewController performSegueWithIdentifier:sender:] when you want to trigger the segue.