How to addsubview to a view on class1 from class2? - objective-c

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

Related

How to create simple table view controller in code only

I need the same type of table view controllers in my app many times and would like to create a more generic table view controller which I can use over and over again.
These table view controllers are quite simple and show only the contents of an array, put a check mark to the selected table view cell and return the index of the selected table view cell to the calling view controller after the Done button in the toolbar has been tapped.
Currently I create each one of these table view controllers directly in Storyboard and instantiate them by using segues.
Would it be possible to do this in code only (without using Storyboard or xibs)?
What would be the best way to instantiate and push them onto the navigation controller stack (each one will be shown in a view controller).
It's trivial to do this in code. You create your view controller class just like you normally would (extend UITableViewController). Implement all of the same table view data source and delegate methods. All of that is the same.
When you want to use the table view controller you just do:
MyTableViewController *vc = [[MyTableViewController alloc] init];
[self.navigationController pushViewController:vc animated:YES];
I would define your MyTableViewController init method like this:
- (id)init {
if ((self = [super initWithStyle:UITableViewStyleGrouped])) {
// any other initialization
}
return self;
}
BTW - I have an app with over 100 view controllers in it and I've never used Interface builder or storyboards. It's all code.
Would it be possible to do this in code only (without using Storyboard or xibs)?
Yes. Anything you can do in a storyboard or .xib file, you can do in code:
MyViewController *vc = [[MyViewController alloc] initWithNibName:nil bundle:nil];
Note: the default behavior for a view controller is to load its view from a .xib with the same name as the view controller's class when you pass nil for the .xib name, e.g. MyViewController.xib for the example above. So the line above creates the view controller in code, but will still load the view from the .xib. If you want the view created programmatically as well, override -loadView.

Parameter passing between two views

I use a first view (a class) where there is a button that shows me one second view (another class).
display looks like this:
listContactsViewController viewController * = [[listContactsViewController alloc] init];
UINavigationController * vc = [[UINavigationController alloc] initWithRootViewController: viewController];
[self presentModalViewController: vc animated: YES];
Then in the second view, I select the rows and then I have an "add" button that to display the first view as this:
[self dismissModalViewControllerAnimated: YES];
My problem is that in the second view I have an NSMutableArray that I would like to send to the first view.
If you have an idea.
Thank you.
There are many way to solve this.
Quick: in your second view controller
listContactsViewController
define a delegate property which holds a reference to the presenting controller (the one where you would like to use the NSArray created in listContactsViewController. Then, before dismissing the view controller, call a method in the delegate interface so that your presenting controller can get a copy of the array.
This is just a quick solution to your problem, though, not the best one.
A more correct solution would be to create a "model" object that is accessible from any controller in your app (a singleton would do) that holds the relevant data: listContactsViewController stores the array into the model; the presenting controller gets it from there.
Use Delegates and Protocol.
Refer this tutorial : Passing data between views tutorial – using a protocol & delegate in your iPhone app.

Switch views - UIViewController to UITabBarController

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];

UIViewController and UIImagePickerController: Unable to create and managing views as expected

I have a UIViewController subclass that contains an instance of UIImagePickerController. Let's call this controller CameraController. Among other things, the CameraController manages the UIImagePickerController instance's overlayView, and other views, buttons, labels etc. that are displayed when the UIImagePickerController, let's call this instance photoPicker, is displayed as the modal controller.
The photoPicker's camera overlay and the elemets that are part of the CameraController view hierarchy display and function as expected. The problem I'm having is that I cannot use UIViewController's default initializer to create the CameraController's view heirarchy.
I am initializing CameraController from within another UIViewController. Let's call this controller the WebViewController. When the user clicks on a button in a view managed by WebViewController, the launchCamera method is called. It currently looks like this:
- (void) launchCamera{
if (!cameraController) {
cameraController = [[CameraController alloc] init];
// cameraController = [[CameraController alloc] initWithNibName:#"CameraController"
// bundle:[NSBundle mainBundle]];
cameraController.delegate = self;
}
[self presentModalViewController:cameraController.photoPicker animated:NO];
}
I want to be able to create CameraController by calling initWithNibName:bundle: but it's not working
as I'll explain.
CameraController's init method looks like this:
- (id) init {
if (self == [super init]) {
// Create and configure the image picker here...
// Load the UI elements for the camera overlay.
nibContents = [[NSBundle mainBundle] loadNibNamed:#"CameraController" owner:self options:nil];
[nibContents retain];
photoPicker.cameraOverlayView = overlay;
// More initialization code here...
}
return self;
}
The only way I can get the elements to load from the CameraController.xib file is to call loadNibNamed:owner:options:. Otherwise the camera takes over but no overlay nor other view components are displayed. It appears that a side-effect of this problem is that none of the view management methods on CameraController are ever called, like viewDidLoad, viewDidAppear etc.
However, all outlets defined in the nib seem to be working. For example, when the camera loads a view is displayed with some instructions for the user. On this view is a button to dismiss it. The button is declared in CameraController along with the method that is called that dismisses this instructions view. It is all wired together through the nib and works great. Furthermore, the button to take a picture is on the view that servers as photoPicker's overlay. This button and the method that is called when it's pressed is managed by CameraController and all wired up in the nib. It works fine too.
So what am I missing? Why can't I use UIViewController's default initializer to create the CameraController instance. And, why are none of CameraController's view mangement methods ever called.
Thanks.
Your problem is easy but need some steps.
Well... First, if overlay is an IBOutlet, it can not be loaded at init time. So move picker and co in viewDidLoad. Place also here all other items that your say that they are not loaded. They should be loaded there (viewDIDLoad). Check that outlets are connected.
Second, call
cameraController = [[CameraController alloc] initWithNibName:#"CameraController"
bundle:nil];
and ensure that CameraController contains (just) a view, and CameraController inherits UIViewController. Check also file's owner.
And at some time, you may consider that calling :
[self presentModalViewController:cameraController.photoPicker animated:NO];
does not make the CameraController control your picker. Does that make sense to you ?
What does that do regarding your problem ?
It seems you are confusing some things. I try to explain in another way :
The one that controls the picker is the one that is its delegate. Your may consider creating in a MAIN view.
The controller of the overlay (added as subview) is the one that own its view in File's Owner. That may be created from the MAIN view, adding its view as subview of the controller. Basically, it is loaded just to get the overlay, but viewDidLoad, ... won't be called.
That's all and I belive those steps are not ok in your code.
That should give something like :
MainController
Loadcamera {
self.picker = [UIImagePicker alloc] init.....];
self.picker.delegate = self;
SecondController* scnd = [[SecondController alloc] initWithNibName:#"SecondController" bundle:nil];
[self.picker addOverlay:scnd.view];
[self presentModalViewController:self.picker animated:NO];
}
/// And here manage your picker delegate methods
SecondController
// Here manage your IBActions and whatever you want for the overlay

Design an NSView subclass in Interface Builder and then instantiate it?

So I have an NSTabView that I'm dynamically resizing and populating with NSView subclasses. I would like to design the pages in IB and then instantiate them and add them to the NSTabView. I got the programmatic adding of NSView subclasses down, but I'm not sure how to design them in IB and then instantiate them.
I think I got it. Let me know if this is not a good thing to do.
I made a new xib file, set its File's Owner to be an NSViewController and set its "view" to the custom view I designed in the xib.
Then you just need:
NSViewController *viewController = [[NSViewController alloc] initWithNibName:#"MyViewXib" bundle:nil];
NSView *myView = [viewController view];
#toastie had a really good answer. Mine is similar, but requires a bit more explanation.
Let's say you've already got a controller object and you don't want to instantiate a new controller object just to get at a view, and let's say that you're going to need multiple copies of this view (for example, you've designed a custom UITableViewCell in IB and you want to instantiate it again and again from your UITableViewController). Here's how you would do that:
Add a new IBOutlet to your existing class called "specialView" (or something like that). It may also be helpful to declare it as a (nonatomic, retain) property.
Create a new view xib called "SpecialView", and build the view however you like.
Set the File's Owner of the view to be your controller object.
Set the specialView outlet of File's Owner to be the new view.
Whenever you need a new copy of the view in your code, you can simply do the following.
(gratuitous text to get formatting working properly)
NSNib * viewNib = [[NSNib alloc] initWithNibNamed:#"SpecialView" bundle:nil];
[viewNib instantiateNibWithOwner:self topLevelObjects:nil];
[viewNib release];
NSView * myInstantiatedSpecialView = [[[self specialView] retain] autorelease];
[self setSpecialView:nil];
Yes, it's a bit more code than other ways, but I prefer this method simply because the view shows up in the designated IBOutlet. I retain and autorelease the view, because I like to reset the outlet to nil once I have the view, so it can be immediately ready to load a new copy of the view. I'll also point out that the code for this is even shorter on the iPhone, which requires one line to load the view, and not 3 (as it does on the Mac). That line is simply:
[[NSBundle mainBundle] loadNibNamed:#"SpecialView" owner:self options:nil];
HTH!