UISplitViewController reload data - objective-c

How can I call function from UISplitViewController subclass to other ViewController.
I have an application that displays splitview and shows modal popup after. When popup is closed, I need to reload data. So appdelegate looks like this:
[self.window addSubview:splitview.view];
[splitview presentModalViewController:popup_ctrl animated:YES];
On TableViewController I've made funcion reloadData;
I found out that by subclassing UISplitViewController, I can detect closing of popup with -(void)viewDidAppear:(BOOL)animated. I've tried following code:
[[self.viewControllers objectAtIndex:0] reloadData];
However it crashes with NSInvalidArgumentException: unrecognized selector.
What do I have to modify to make the function reloadData work?

Why not explicitly add a property to your SplitViewController that references your TableViewController?
Then you can say
mySplitViewController.TableViewController = myTableViewController;
and later call
[mySplitViewController.TableViewController reloadData];

Related

Cocoa Touch: How can I update the table view everytime I tap on a tab of tabbar?

I'm using iOS 8 and Objective c.
If I do a change in the values in one view, I can't see the reflection on my other tabviews. But if I re-run the app, I can see the reflection on the other tabs. Sometimes it works, sometimes it doesn't. How can I make sure that when I tap on a tabview, it will be reload according to the database?
I'm not sure what you are trying in your code, but you can try to implement the viewDidAppear method with a reloadData in your tableView:
- (void)viewDidAppear:(BOOL)animated{
[self.tableView reloadData];
}
[tableView reloadData] is the one you are looking for , this UITableView method refreshes the table view by calling its delegate and data source methods again to get fresh data.
I solved it!
Here is my code:
"TheMaster" is the main tabview. Here selectedIndex can be 0,1,2.... according to the placement of the tab. The leftmost tab has the index 0, and after that 1,2, and so on.
UITabBarController *controller = [self.storyboard instantiateViewControllerWithIdentifier:#"TheMaster"];
controller.selectedIndex=0;
[self presentViewController:controller animated:YES completion:nil ];

Calling reloadData on same UITableView, but it seems like it's calling on a different one

This has been a headache for few hours now and I finally found out what is actually happening, but I don't know how to solve this issue.
I've got List.h with UITableView properly connected from storyboard:
#property (strong, nonatomic) IBOutlet UITableView *tableView;
Then there's List.m where I set delegates and datasource for my UITableView:
// Set tableview datasource and register class for cell reuse
self.tableView.dataSource = self;
[self.tableView registerClass:[TableViewCell class] forCellReuseIdentifier:#"cell"];
// Set tableview delegate
self.tableView.delegate = self;
// Set tableview cells style
self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
self.tableView.backgroundColor = [UIColor colorWithWhite:0.1f alpha:1.0f];
// Set tableview frame
self.tableView.frame = CGRectMake(0.0, 35.0, self.tableView.frame.size.width, self.tableView.frame.size.height-35.0);
Then on NSNotification I'm trying to [self.tableView reloadData]:
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(doUpdateAppBefore:) name:UIApplicationWillEnterForegroundNotification object:nil];
Also I'm reloading data of tableView on every UIApplicationBecomeActive notification.
Before I close my app and open it up from background to find out if it's reloads the data, I'm moving to another UIViewController and going back, which causes that somehow identifier of my self.tableView changes. I'm checking it in:
NSLog(#"Calling reloadData on : %#");
and at the beginning it gives me:
Calling reloadData on <UITableView: 0x9b09400;....
but after I segue back from another UIViewController it gives me:
Calling reloadData on <UITableView: 0x9b4b000;
which causes that it doesn't actually reload the data after I open up the app from the background state.
I've been thinking... when I segue back from another viewcontroller, viewDidLoad fires again, is it possible that it somehow sets tableView.delegate again and changes something? Just thinking...
Thank you very much for your answers.
It sounds like you have a view controller, push a modal view on top of it, and then want to go back to the original view controller when you're done. So, you set up a modal segue in your storyboard, and then a second modal segue to go back. The problem is that your second modal segue doesn't return to the original view controller, but it creates a new instance of that view controller, and now your have the original view controller, the second view controller, and an unwanted third view controller. Instead of creating a segue, which creates the third view controller, you need to dismiss the second view controller, which then gets you back to your original view controller, and therefore also your original table view. So what you want to do is get rid of the second segue and replace it with an IBAction, put something like
- (IBAction)goBack:(id)sender;
in your .h file. Connect that to your button or whatever you're using to trigger the segue now. Then, in your implementation file, dismiss the modal view like so:
- (IBAction)goBack:(id)sender
{
[self dismissViewControllerAnimated:YES completion:nil];
}
That should get you what you want.
Alternately, and this is probably better, you can use an unwind segue as well. Go to List.h, and create this method:
- (IBAction)unwind:(UIStoryboardSegue *)segue;
Then just implement it, you can leave it blank for now. Then, drag from the button that currently triggers the segue to Exit, and select the Action Segue unwind. That will also get you back.

return to ViewController after presentViewController

Im trying to return to a specific ViewController in it's current state after going from that ViewController to another using presentViewController.
But when I try to close the other ViewController (with dismissViewController) I get a white screen.
RootViewController *rootViewController
= [[UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil]
instantiateViewControllerWithIdentifier:#"RootViewController"];
[self presentViewController:rootViewController animated:YES completion:nil];
This isn't an option either because that instantiates a new viewcontroller and I want the old ViewController in its current state.
Do I need to pass the RootViewController as an argument when presenting the other ViewController or is there another option to return to the RootViewController in its current state?
Yes, there is a way to return original screen.
I met just like problem but solved it with following code line
[self dismissViewControllerAnimated:YES completion:nil];
one way to address this is to avoid having one view controller responsible for presenting and dismissing the other one.. what you can do is create a controller of controllers (give it a singelton method).. and have that object basically keep a reference to any view controller you are interested in maintaining its state. That way you wouldn't have worry about what's going on behind the scenes when you dismiss or present a view controller.

Navigating back to main ViewController dismissViewControllerAnimated dilemma

I have 2 ViewControllers directly connected with a push segue. I am navigating from first to second view controller by calling [self performSegueWithIdentifier:#"segueIdentifier" sender:sender]. On the second one I have an IBAction method that is bound to a "Done" button. Pressing that button should basically cause the first view controller to be displayed (sort of a back button). I managed to do that with:
NSArray *viewControllers = self.navigationController.viewControllers;
[self.navigationController popToViewController:[viewControllers
objectAtIndex:0] animated:YES];
I did try to achieve the same effect by using:
[self dismissViewControllerAnimated:YES completion:nil];
No matter what I tried though this didn't do the job. I am trying to understand what exactly am I missing but I can't figure it out. Does dismissViewControllerAnimated method work only with Modal segues ( this is the only thing that came to mind ).
Thank you
Yes,
- (void)dismissViewControllerAnimated:(BOOL)flag completion:(void (^)(void))completion
is when a UIViewController is displayed modally.
- (UIViewController *)popViewControllerAnimated:(BOOL)animated
should do what you are seeking.
So basically, in your second VC:
[self.navigationController popViewControllerAnimated:YES];
You will save you a lot of trouble if you read the UIViewController and UINavigationController references. Twice ;)

pushViewController iphone not working

i am unable to get the pushViewController to work on a View Based Application on the iPhone. On my 'ProjectViewController' i have a IBAction with the following code :
-(IBAction)switchAugmented
{
ARViewController *viewController = [[ARViewController alloc] initWithDelegate:self];
[self.navigationController pushViewController:viewController animated:YES];
[viewController release];
}
When i run the program and press ibaction nothing happens. Besides that statement above do i need to do anything else to make the view appear? what am i missing?
(...) on a View Based Application (...)
You just have no UINavController! Try to embed your main view in UINavigationController and everything will start working.
Double check to make sure that the button you are pressing is connected to the right method in interface builder. Also try putting an NSLog statement in the switchAugmented to see if the method is getting called.
You also have to check and see if you have a UINavigationController instance, otherwise you won't be able to push a new view controller.
You won't be able to push a new view controller in a View Based Project. You need to create a Navigation Based Project or add an instance of the UINavigationController in your Main.nib (if your using a nib file) only then will the push view controller will work