I have a problem on how to properly do a certain kind of action.
The image below shows a UIViewController, but the second part of the view is a custom UIView (the one with the profile pic, name and Show View button).
The subclassed UIView is allocated using this code:
profileView = [[GPProfileView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 70)];
profileView.myTripGradientColor = YES;
[self.view addSubview:profileView];
The problem is of course, that the button on the UIView can't show any view, since it's only the UIViewController that can push another ViewController to the window(correct?).
The UIView is used in several places in the app and needs to be added easily and have the same behavior across the application.
This worked great until I added the button, and I'm starting to think I've made this wrong, and there has to be a better way to do it (maybe change the UIView to something else?).
I was thinking I should be able to call:
self.superview
And then somehow get the ViewController so I can push another ViewController into the view hierarchy, but nope.
Any suggestions and a tips on how to do this correctly?
UPDATE:
I have no idea on how to push another UIViewController from the button.
What should I do in this method when pressing the button in the UIView:
- (void) showViewButtonTouched:(UIButton*)sender {
GPProfileSocialFriendsViewController *friendsSettings = [[GPProfileSocialFriendsViewController alloc] init];
}
How do I push GPProfileSocialFriendsViewController?
Your - (void) showViewButtonTouched:(UIButton*)sender method should be in your controller and would probably be better named - (void) showView:(UIButton*)sender or - (void) showProfile:(UIButton*)sender so it clearly denotes what it does (not how you got there).
It's not the view's responsibility to manage transitions from a state to another. If you move your method to your controller, your problem is no more (you can easily access self.navigationController or push directly if you don't have an navigation controller like this:
[self presentViewController:vcThatNeedsToBePushed animated:YES completion:nil];
I think you can create weak reference in GPProfileView on UIViewController. Like this:
#property (weak, nonatomic) UIViewController *rootController;
when you create GPProfileView, assign rootController-property:
profileView = [[GPProfileView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 70)];
profileView.myTripGradientColor = YES;
profileView.rootController = self; // if view created in view controller
[self.view addSubview:profileView];
and in implementation of button selector:
self.rootController push... // or pop
May be this not correct, but you can try
You could let the view controller push the next view controller when the button is pushed. The view controller can add a target/action on the button, so that the action method in the view controller is called on the touch up inside event.
Related
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
I'm having trouble connecting the dots between code and .xib files.
If I want to add a series of UIButtons programmatically to my view controller, how would I go about doing this from a separate class?
For instance, if I have MainViewController.m, which is set as the root view controller in Xcode, how can I add a UIButton to that view controller from SecondViewController.m? Is this even possible?
I would essentially like to place all of my "user interface" code in a separate class.
Thanks
To do this, create a UIButton *myButton programmatically and then call [mainViewController addSubview:myButton];. This may mean you need to store a MainViewController * property in your SecondViewController class.
Important methods and properties for a UIButton instance (essentially, just take a look at the documentation, but here's a minimal set of stuff to get you started):
+[UIButton buttonWithType:buttonType] - Make sure if you're doing anything remotely custom to use UIButtonTypeCustom here (it doesn't give you any default background images or otherwise to have to nil out)
setFrame: - Position the button relative to its container and set the size, for usability reasons the width and height should be at least 44 pixels (as mentioned here).
setTitle:forState: - UIControlStateNormal will act as the default properties for other states too, so you may only need to set the text here
setBackgroundImage:forState: - use UIControlStateNormal and UIControlStateHighlighted/UIControlStateSelected primarily, UIControlStateDisabled if you wish to show it grayed out or inaccessible at any point.
setImage:forState: - Use for an icon next to the button text (like an arrow pointing down for Save or up for Load, etc)
setEnabled:, setHidden:, setSelected: - Transition between different button states. setHighlighted: happens automatically when you tap the button.
addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside - TouchUpInside is almost always what you want for a simple button press, I'm using a method named buttonClicked: here to handle my button press.
Oh, and if you use [[UIButton alloc] initWith...] don't forget to [myButton release] once it's added to the mainViewController :)
use this
#import "MainViewController.h"
#interface SecondViewController
{
MainViewController *mainView;
}
#property(nonatomic, retain) MainViewController *mainView;
-(void)addButtons;
In your implementation
#synthesize mainView;
-(void)addButtons
{
UIButton *add = [UIButton alloc] init];
//do necessary stuff on button here
[self.mainView addSubview:add];
[add release];
}
In your MainViewcontroller.m
#import "SecondViewController.h"
-(void)viewDidLoad
{
[self superViewDidLoad];
SecondViewController *second = [SecondViewController alloc] init];
second.mainView = self;
[second addButton];
[second release];
}
I have subclassed UIViewController like so:
#interface MyClass : UIViewController
I dont have a xib file for the controller, instead I would just like to use a blank UIView and I will layout elements programmatically on that. The problem arrises when I try and push this view controller.
MyClass * thing = [[ImageGallery alloc] init];
[self.navigationController pushViewController:thing animated:YES];
A new title bar is animated in, but there is no view, its see through, so I end up seeing a static background I set on my main "window/view". How should I properly subclass a UIViewController without a xib?
What you have described is correct behaviour so far.
You will want to override the -(void)loadView method, and after the [super loadView]; call, you can set your background colour and begin to place the objects in programatically, that you desire.
I'm attempting to create a subview inside a regular view. When a button is clicked that is contained in this subview, it will flip over and show a new subview. This will is meant to simulate a card flipping over on a table. I have a DetailViewController that is an empty xib, but when it's loaded it loads another controller called CardFrontViewController that actually contains the subview (front of the card) all contained in a xib. Once the button inside the subview, it should load the subview that is contained inside the CardBackViewController xib.
Inside DetailViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
if (!self.cardFrontViewController)
{
self.cardFrontViewController = [[CardFrontViewController alloc] initWithNibName: #"CardFrontViewController" bundle: nil];
[self.view addSubview: self.cardFrontViewController.view];
}
[self configureView];
}
Inside CardFrontViewController
- (IBAction)flipToAnswerCard:(id)sender
{
if (!self.cardBackViewController)
{
self.cardBackViewController = [[CardBackViewController alloc] initWithNibName: #"CardBackViewController" bundle: nil];
}
[UIView transitionWithView: self.cardFrontContainerView
duration: 1.0
options: UIViewAnimationOptionTransitionFlipFromTop
animations: ^{ [self.cardFrontSubView removeFromSuperview];
[self.cardFrontContainerView addSubview: self.cardBackViewController.cardBackSubView]; }
completion: nil];
}
When I click the button to flip over the card, the card flips, but the view that is displayed is empty, meaning that the self.cardBackViewController.cardBackSubView is not loaded inside.
If I do [self.cardFrontContainerView addSubview: self.cardBackViewController.view] inside the flip card method it loads the entire xib inside, but I really just want a view inside. I'm not sure what to do here.
You don't need a UIViewController if all you want is just to load a view, with some IBOutlets.
Just use [[NSBundle mainBundle] loadNibNamed:#"myViewNib" owner:self options:nil] from your DetailViewController, and if IBOutlets corresponding to ne 'card' NIB exist, they will automatically be linked (to the owner).
If you really want a different class to handle this 'card' (and 'own' the IBOutlets) does it necessarily need to inherit from UIViewController? NSObject can sometimes be a good candidate too.
Finally, If you really really want to nest UIViewControllers, this will only work in iOS5.
To support previous iOS versions, you would eventually have to manually call some UIViewController's life-cycle methods (willAppear, didAppear...), pass certain events from you master UIViewController to its detailViewController (like willAnimateToRotation), and maybe some other tricks.
If you just want to flip subviews within a main view, the answer that worked for me was found here: https://stackoverflow.com/a/9028156/1319615
I am trying to work my way through basic iPhone programming and I have a good basic understanding of how Interface Builder works, so I decided to try my hand at doing the views programmatically. I have gone through the ViewController Apple guide and searched everywhere and I cannot seem to find a solution to my problem. This leads me to believe it is a very simple solution, but I am just really banging my head against the wall. Basically all I am trying to do is create a view that gets main window as a subview. I know that if self.view is not defined then the loadView method is supposed to be called, and everything is supposed to be set up there. Here is the current state of my code:
The delegate:
- (void)applicationDidFinishLaunching:(UIApplication *)application {
StartMenuViewController *aViewController = [[StartMenuViewController alloc] init];
self.myViewController = aViewController;
[aViewController release];
UIView *controllersView = [myViewController view];
window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
[window setBackgroundColor:[UIColor redColor]];
[window addSubview:controllersView];
[window makeKeyAndVisible];
}
The view controller:
- (id)init {
if (self = [super init]) {
self.title = #"Start Menu";
}
return self;
}
// Implement loadView to create a view hierarchy programmatically, without using a nib.
- (void)loadView {
UIView *startView = [[UIView alloc] initWithFrame:[UIScreen mainScreen].applicationFrame];
[startView setAutoresizingMask:UIViewAutoresizingFlexibleHeight|UIViewAutoresizingFlexibleWidth];
[startView setBackgroundColor:[UIColor greenColor]];
self.view = startView;
[startView release];
}
Thanks for the help in advance!
Are you sure that you're inheriting from UIViewController and not overriding the implementation of - (UIView*)view?
EDIT: More info:
UIViewController has a special implementation of the "-(UIView*) view" message so that when it's called, the loadView method is called if the view member variable is not set. So, if you provide an implementation of "- (id)view" in your subclass, (or a property named view) it will break the auto-calling of "- loadView".
Just to document a "loadView is not called" case:
I wrote a 2 UITableViewController(s) to handle detail data for a master ViewController. Since the devil was in #2, I made a simple UITableViewController for #1, and referenced it in the XIB for the "master" ViewController.
When I was done with #2, I could simply copy the code to #1, remove the complicated code, and go on with life.
But to my dismay and several days work, no matter what I did, viewLoad was not being called for my simple #1 UITableViewController.
Today I finally realised that I was referencing the UITableViewController in the XIB to the master ViewController program. - and of course, loadView was never being called.
Just to help some other dork that makes the same mistake....
Best Regards,
Charles
viewDidLoad only if the view is unarchived from a nib, method is invoked after view is set.
loadView only invoked when the view proberty is nil. use when creating views programmatically. default: create a UIView object with no subviews.
(void)loadView {
UIView *view = [[UIView alloc] initWithFrame:[UIScreen
mainScreen].applicationFrame];
[view setBackgroundColor:_color];
self.view = view;
[view release];
}
By implementing the loadView method, you hook into the default memory management behavior. If memory is low, a view controller may receive the didReceiveMemoryWarning message. The default implementation checks to see if the view is in use. If its view is not in the view hierarchy and the view controller implements the loadView method, its view is released. Later when the view is needed, the loadView method is invoked
again to create the view.
I would strongly recommend you use interface builder for at least your initial Window/View.
If you create a new project in XCode you should be able to select from one of many pre-defined iPhone templates that come with everything setup.
Unless I am reading this wrong, you did not associate any view with the the controller's view property like this
myViewController.view = controllersView;
So as far as Cocoa is concerned the view you are setting in the window has no controller to call loadView on. loadView is a View controller, not view, method. The view you assign to the window is not associated with any view controller. So your view controller loadView method is never called. Get it? The view you are trying to display, has no view controller associated with it.
When you use interface builder to create views you can link the UIView object you created in IB to the view property in the controller in IB which the framework automatically
But if not done in IB you have to set it