Is it possible to view the viewcontroller behind the displayed one? I have a viewcontroller with a scrollview, which has imageviews added as subviews and would like the view that presented this viewcontroller to be visible behind the presented view controller.
I have set all the views, the viewcontroller view too to have a clear color background, but still there is a black background. when I dismiss the viewcontroller, I see 2 layers being dismissed. one has alpha dropped, the other not.
Is there an easy way to make this effect possible?
Its not possible. When a new view controller is pushed or presented as modal view, the previous view controller will be removed from the display(may be UINavigationController/iOS hides it). The rule is only one view controller would be visible at a time. So you will see the color of your window(the black color you've mentioned) in the background.
What you could do is make a screenshot before displaying the other controller. and send this image to new controller to be displayed as background.
This will only work for static content, but you could do something like the curl display.
You can do this but the truth is what EmptyStack says.
You can use setFrame of the subView and add it on the viewController. Also use below method to set the index of the added View. By default currentView has Index 0.
[self.view insertSubview:myView atIndex:0];
or you can try below methods as per your logic
insertSubview:aboveSubview:
insertSubview:atIndex:
insertSubview:belowSubview:
addSubViews:
bringSubviewToFront:
removeFromSuperview:
Related
Is there a way to use UINavigationController with a background image that remains still and does not animate when the view controllers are pushed or popped?
Same effect can be achieved by having a paged UIScrollView and a UIImageView underneath it but I would like to use UINavigationController so methods like viewWillAppear, viewDidDisappear are called, and I can use UINavigationController's logic for popping and pushing view controllers.
Yes it is quite easy. Add an image to the window (or whatever is at the back of your view heirachy), then make the uiviewcontroller main views have transaparent backgrounds. This works on iOS 4 and above.
Im writing an application which the main view controller is a UIViewController. It has some icons in a grid and I want to dismiss (sliding down) this grid when one of the icons is clicked. This I've done already. The problem is: when the grid is dismisseed I want another View to come from the top of the screen. This view is in this same root view controller. But I want to display the content of other view controllers in this view. For example: I want this view to show a UINavigationController with a UITableView inside it, so the user can navigate through TableViews.
I'm doing this:
HorariosViewController *horarios = [[HorariosViewController alloc] init];
[vuashView addSubview:horarios.view];
HorariosViewController is a UINavigationViewController. It shows me only a blue NavigationBar and changes like self.navigationItem.title = #"Title" won't work.
Thanks!
You can show another view controller's views as subviews but their outlets and actions remain linked to their original view controller unless you write code to make new connections, so self.whatever shouldn't be expected to affect the other view controller's properties.
(Also, if HorariosViewController is a UINavigationController, it shouldn't be created as a UIViewController.)
One approach is to have the navigation controller already there, with the icon grid presented modally on top of it. (you can set the view up this way without animations, so the user doesn't see the navigation controller underneath).
Then, when it's time for the grid to go away, it can call dismissModalViewController on itself with animation.
So before I push a new viewController onto the stack in a certain view, I set the navigationBar to hidden I notice that it disappears before the next screen gets pushed and the slide animation happens (because I need a UIToolbar at the top).
So question #1: is there a way to push a new view controller and setting the navigationbar to hidden, and not getting the hide animation until after the new view controller is on screen. it looks funny that the navigation bar hides then pushes the new view controller.
Once the new view controller is present, when I pop it off, I set the navigation bar back
[self.navigationController.navigationBar setHidden:NO];
But when it is popped, the navigationbar is not back any more. Is it because this navigationBar is for the current navigationController and not the new one that is being presented after the pop? (question #2)
Question 3: Realizing it isn't showing my navigationBar, in the viewController that gets presented after the pop, in its viewDidAppear, I added
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
[self.navigationController.navigationBar setHidden:NO];
}
which shows the navigationBar, but the view size is incorrect since it seems like once the navigation bar was hidden, the rest of the view took up the empty space, and then the navigationBar is on top of the content. Is there anything I can do about this? Or am I approaching it incorrectly with push and pop?(question #3).
Thanks!
I was running into the very same problem (only in reverse: I was starting from a NavigationBar being hidden and pushing a view where I wanted the NavigationBar visible), and there's actually an extremely easy fix.
Simply replace your calls:
[self.navigationController.navigationBar setHidden:NO];
with
[[self navigationController] setNavigationBarHidden:NO animated:YES];
In my code, I call these statements in the - (void)viewWillAppear:(BOOL)animated methods of each respective View Controller.
I just tried this solution in the order you are using (visible, then hidden), and it seems to work just as well.
Interesting issue. You could try changing the hidden property in viewWillAppear and viewWillDisappear, but it seems like that might not give the desired results either.
Can you present the view controller modally instead of making the navigation bar disappear? If it's the last view controller on the stack, that would be possible. It might also make more sense to the user to see a view controller presented differently. This might indicate to the user that navigating away from this view controller is no longer done with the Back Button. It could be more reasonable than having the navigation bar just disappear.
If you still wanted the view controller to slide in from the right, I don't think it can be done with a modal view controller. But, you could do that by animating a view that fills the screen. (You just add the view with a frame that has origin.x equal to the width of the screen. Then, in the animation, you change origin.x to 0.0. Let me know if you need more detail on this.)
However, I would recommend presenting the view controller in a different manner from the way a view is generally presented by a navigation controller. Because, essentially, you are no longer letting the user navigate away from this view as he/she generally would from within a navigation controller. (So, my response to question #3 would be 'yes'.)
i need to shrink the height of a UINavigationBar (attached to the UINavigationController)
i've done this via the UINavigationControllerDelegate's navigationController:didShowViewController method, and it's working fine.
the problem is the visible viewcontroller that's in the main view. it wasn't resizing itself to reflect the new navbar height. thus, the didShowViewController method also resizes the viewcontroller's view frame, which works fine.
however, when i go to push on a new ViewController, or pop, i always see the view shift down to the original position during the animated transition to the next view. then, due to the code i have in the didShowViewController in the NavControllerDelegate, it shifts it back up.
i'm curious as to the best way to ensure that the shift down never happens.
i tried placing the code that resizes the frame into the willShowViewController, but that doesn't do anything.
i've also made sure that the UIView's frame that is the view of the UIViewController that's being popped, is also of the proper/shifted dimensions. no go there.
it's like i need to intercept the drawing actions after the pushViewController is invoked, and before the UINavigationController's didShowViewController is called.
i've been staring at my code for hours & hours... not getting anywhere. hopefully this makes sense to someone out there.
thanks!!!
Another option I think would be to set the NavigationControllers navigationBarHidden equal to YES. This will hide the nav bar completely and then you can then draw whatever view you want in the place the bar would have resided. Just put controls on the view that wrap the navigation methods (push, pop, etc...). It might be a challenge to get it to have the same style as a nav bar though.
I've been working pretty extensively the last couple months with UIImagePickerController, particularly with the new capabilities in OS3.1 and newer to overlay views on-top of the camera view. This has worked just fine.
However, I am currently working on a project where I'd like to be able to display the camera view of the UIImagePickerController within an existing view. Essentially, the exact opposite of what I've currently been doing.
An example would be a View Controller with navigation components (Think top and bottom horizontal bars with gradients), and upon tapping a button on one of these bars, then content area displays the camera view. The shutter animation would should up, and the top and bottom navigation bars would remain always on-top.
I've had success adding the UIImagePickerController to the window view, as well as presenting it modally, but haven't had any luck adding it as a subView.
ex:
[window addSubview:camera.view];
[self presentModalViewController:camera animated:YES];
All you need to do is call viewWillAppear and viewDidAppear.
Here is an example where _pickerController is an instance of UIImagePickerController:
[self.view addSubview:_pickerController.view];
[_pickerController viewWillAppear:YES];
[_pickerController viewDidAppear:YES];
Call viewWillAppear:YES on the image picker controller after adding its view to your view. Skip the modal view controller business.
I don't think the API provides direct access to the actual view of the UIImagePickerController. The class is actually a subclass of UINavigationController so I don't think it has an actual view itself but rather manages the calling of its subcontrollers and their views.
When you call the UIImagePickerController modally, its doesn't add the views it controls as subviews to the window (or any other view). That is what a modal view means. It presents the view off to the "side" of the view hierarchy.
Even if you could hack this together, I think Apple would reject it as not being part of the API and for violating the HIG.