How do you declare a view controller with Objective C?
Sorta depends. Just to give one example, let's say you have a new project setup using apple's "View based app" template. If you want to have a new view "slide up" and replace your current view you can do this. Add a new file to you project of type 'UIViewController subclass', and select the 'With XIB for user interface' option. Now, in you code, when you want to display this view do this:
MyViewController *myViewController = [[MyViewController alloc] initWithNibName:#"MyViewController" bundle:nil];
[self presentModalViewController:myViewController animated:YES];
[myViewController release];
This is assuming that your new UIViewController subclass name is MyViewController and the the XIB is named MyViewController (so you should have MyViewController.c(.h)(.xib)
Related
I have one UIView that I want to use in every of my UIViewControllers. The main UI is designed with Storyboard. The extra UIView has its own XIB.
So I don't want to put the UI of the extra UIView by hand into every UIViewController, and connect the outlets on every UIViewController. So I thought maybe it is possible to create the UI, and the connections in one XIB and then somehow reuse it. Is this possible? If yes how?
Just add this line to your ViewControllers to have a reference to your custom view:
YourView *yourView = (YourView *)[[NSBundle mainBundle] loadNibNamed:#"YourXIB"
owner:self
options:nil].firstObject;
But since you want this custom view in all of your ViewControllers, I recommend having one UIViewController subclass that contains the line above, then subclass that UIViewController for each additional one in your project. That way you'll have a reference to your custom view in each ViewController, but only have to write this line once.
I think it is possible by keeping the same name in the function initWithNibName:, so you can do this in one of your controller:
UIViewController *oneViewController = [[FirstViewControllerClass alloc] initWithNibName:#"MyXIBThatWillStayTheSame" bundle:nil];
[self presentModalViewController:oneViewController animated:YES];
and do this in another one:
UIViewController *anotherViewController = [[AnotherViewControllerClass alloc] initWithNibName:#"MyXIBThatWillStayTheSame" bundle:nil];
[self presentModalViewController:anotherViewController animated:YES];
I'm trying to do a really simple thing - I've got a main Xib file for the whole app and another Xib file for a small view.
I want the small view (Xib called "additionalView.xib") to appear in the first Xib ("ViewController.xib").
I have succeeded to do so in the "ViewController.m" but I want more - I want to do it from "additionalView.m"
There is a method I created called "openView:" in "additionalView.m" and it looks like this:
-(IBAction)openView:(id)sender
{
ViewController *vc = [[ViewController alloc] init];
NSArray *nibObjects = [[NSBundle mainBundle] loadNibNamed:#"additionalView" owner:self options:nil];
UIView *nibView = [nibObjects objectAtIndex:0];
[vc.view addSubview:nibView];
}
The method is being called and the lines are being read by the debugger - but nothing happens.
No crash - No error - No small view in bigger view.
Why is that?
I know that the last line is probably what's
screwing everything up but i don't know how to put it correctly.
Your problem is that ViewController *vc = [[ViewController alloc] init]; creates a new view controller. Because it's new, it's not the one that already exists in the view controller hierarchy that's managing the display.
Your method needs to access the existing view controller. How it does that depends on your app's structure and which object has a reference to the original controller object.
Try
[self.view addView:view.vc];
However, I'm not sure what is you view structure here. You say your -(IBAction)openView:(id)sender is in your "additionalView.m", but it is not the main view controller, correct? You need to do this in the main controller, so basically move the openView: method to your ViewController.m
And you normally need a separate view controller for each view to keep things neat and separate, so the additionalView.m should be an instance of UIViewController, which you can then create from your main view as follows:
-(IBAction)openView:(id)sender
{
AdditionalView *vc = [[AdditionalView alloc] initWithNibName:#"additionalView"];
[self.view vc.view];
}
You have options ... First you don't need to create a view controller vc if you just need the view . Create a uiview and add it .
Option 1: pass a ref to the app vc as suggested above and then :
[appVC.view addsubview:additionalView]
This will add it to main.
Use a view controller manager / ref in the app delegate that you can refer to as delegate and add your view to the current showing view.
Hope this helps
I know different versions of this question has been asked before but I'm really stuck here. I'm trying to get my app to push a new view from my app delegate when getting:
-(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)localNotif {
And I put the following code in there:
MyViewController *myViewController = [[MyViewController alloc]init];
nvcontrol = [[UINavigationController alloc] initWithRootViewController:myViewController];
[nvcontrol.navigationBar setTintColor:[UIColor blackColor]];
self.window.rootViewController = nvcontrol;
and from this, I get a black view (which myViewController should not have) with a black navigation bar.
What am I doing wrong here?
As I've outlined above, you can use storyboard to set the initial view controller.
Note that if you have a view controller set up in storyboard and then you create a view controller in the application delegate, the view controller you created won't look like your one in storyboard. This is because you are making an instance of the CLASS, but the program has no way to associate this with your layout.
I have this scheme:
I create a storyboard and subclass the UIViewController to MyViewController and link it to correct class. Now I can have full access to this controller. But...
I want send a message to this object in application:didFinishLaunchingWithOptions: but I do not see how can I do it. Because I do not create the interface in code, I can't link it.
How can I do this?
You can get a reference to your UIViewController by using the code below, which assumes it is the only UIViewController. The [[navigationController viewControllers] returns an array of the viewcontrollers, so you could grab the one you want.
UINavigationController *navigationController = (UINavigationController *)self.window.rootViewController;
MyViewController *myViewController = (MyViewController *)[[navigationController viewControllers] objectAtIndex:0];
I am curious if you could use the interface builder (Storyboard) and control drag from the view controller to the delegate .h file to create an IBOutlet...I do not have accesss to try that now, but will try when I get home....I could not get the drag method to work...
I have made a very simple Navigation based app (UIViewController). The view has a single button on the Main RootViewController.
Next, I made 2 classes: TabOneViewController, TabTwoViewController. All good. I then created a new Class TabBarViewController. I opened up the NIB file and dropped on a ``UITabBarController onto it. The two tabs it creates in it by default were assigned (respectively) to my TabOne and TabTwo view controllers.
strong text
Then in my TabBarViewController, I made an IBOutlet for a UITabBarController, synthesized it etc etc. I linked it up in Interface builder via the "files owner".
In the RootViewController, I linked the button to my "pushView" method, and in this pushView method, I have the following code:
- (IBAction) pushView {
TabBarViewController *controller = [[TabBarViewController alloc] init];
[self.navigationController pushViewController:controller animated:YES];
[controller release];
}
The end result is it DOES push a view, but I cannot see the tab bar at the bottom, let alone any of the pages I've added to the controller.
What am I doing wrong? Why can't I link it in IB?
I am not 100% sure if that's allowed.. because you already have one tabBarController as rootViewController, and you dropped one more tabBarController as first tab controller, tabs ll overlap, considering amount of real estate you have on your iPhone, it make sense to not allow a tabViewController inside another
First, you need to allocate your view controller with your nib:
TabBarViewController *controller = [[TabBarViewController alloc] initWithNibName:#"YourNibName" bundle:nil];
Secondly, in IB, click the UITabBarController and go to the identity inspector and make sure you select your custom class. That said, unless you are overriding or adding some functionality you probably don't need the custom class at all, simply use a UITabBarController directly:
UITabBarController *controller = [[UITabBarController alloc] initWithNibName:#"YourNibName" bundle:nil];