I couldn't find any tutorial that i could understand about switching views but i found out that i can switch them by changing the window's rootViewController property.
The problem is my other view has 2 UITableViews in it, but they don't respond to swipes when the controller just became the rootViewController, but after i turn my ipad 90 degrees the view changes to landscape then it starts to work.
Can anyone tell me how to make them work when the view is loaded?
You can't change directly the windows rootViewController property and have it to work, because the system doesn't get notify that that change occurred. That is why the change took effect only when the system asked for that view again.
You need to use a method to change it. Depending on your architecture you may want to use a method from UIViewController
transitionFromViewController:toViewController:duration:options:animations:completion:
UINavigationController :
setViewControllers:animated:
UIView :
transitionFromView:toView:duration:options:completion:
Related
I'm a new iOS programming and I'm developing a simple iPhone game that needs to run in landscape only. I've ...
set supported orientations in the target settings
added the req. plist item (initial interface orientation)
overridden shouldAutorotateToInterfaceOrientation to return YES only for landscape modes
.. and the app "looks" correct, but there are a few odd things going on.
Issue 1 - I'm trying to manually position my views and not rely on autolayout. I've got a UIView in a NIB that I'm loading that needs to be positioned 150px from the right edge of the screen. I have to get the UIViewController's view's height (not width) to correctly position it - like it's not rotated to landscape at this point in the code.
Issue 2 - Implementing a UINavigationController to go from the title screen to the game interaction. When I'm pushing the interaction UIViewController to the stack, it slides in from the right like it's supposed to. When I go back to the title by popping the interaction, it slides UP to the title. It's seems like it's rotating back to portrait?
I think there is something very basic that I'm missing, but I can't find it in my app code. I've gone over the lists for a landscape app but they don't mention more than the list above.
Are there any other things/settings/methods to override that I should be on the look out for?
You need to set shouldAutorotateToInterfaceOrientation in your other viewControllers as well. Especially the ones displayed inside your UINavigationController.
Issue 2:
Don't use many UIViewController's. Use one view controller. Create one main UIViewController and for other UIViewController's just do:
[mainviewcontrl presentModalViewcontroller: child_viewcontrl animated: YES];
For delete a child view controller, use
[child_viewcontrl dismissModalViewControllerAnimated: YES];
here is my problem, I hope someone can help me.
My iPad app is made like this : I have several viewControllers added as tabs in a tabBarController added to window in my appDelegate. In each of these viewControllers I got two navigationControllers with one viewController in.
Appdelegate
TabBarController
viewController
navigationController
viewController
navigationController
viewController
viewController
navigationController
viewController
navigationController
viewController
Everything work fine in simulator but when I run it on device I got this warning :
Using two-stage rotation animation. To use the smoother single-stage animation, this application must remove two-stage method implementations.
It only happen when I run it on a device in landscape mode. The first navigationController of the default view shown by the tabBarController take all the screen width (not important here but it's to explain that this warning makes my layout going crazy). In portrait nothing is traced in the console.
I read many things about this message but I can't find any solution to make it go away.
I'm sure it's a story of shouldAutoRotate or something like this.
I also notice that if i remove the tabBarController and simply add my first viewController to window, the message is not shown.
Very strange... please help :)
I think you should rely on the standard UISplitViewController available under iPad. This controller is what is used under the Settings app and various other apps.
If you do not feel comfortable with such a tool, you can take a look at the APSplitViewController plugin developed by slatvick on GitHub. This could solve a lot of your problems, I hope.
Edit
Googling about this issue, I found out that this warning appears when you create a wrong hierarchy of view controllers. In this case, you are pushing two navigation controllers inside a view controller, even if a view controller is not meant to contain different navigation controller. Probably there could be a problem related on how you send up to the parent view controller methods like viewDidLoad or viewWillLoad: etc. You should try to understand if you are passing all these call correctly to the parent view controller from the inner navigation controllers.
If I want to replace one screen of an app with another, but I don't use a navbar/tabbar controller, then I could just remove oldViewController.view from window and add newViewController.view to it. That's all, now newViewController will get rotation events, etc.
But UIView does not reference "its" controller, so how is this possible, how iOS know it should make newViewController an active one? Does iOS do some magic, it internally references controller from view or what?
UPDATE:
I think I was misunderstood: I don't ask how to make some view controller an active one - I know that. I'm just curious, how is it possible that I pass some view to UIWindow object ([window addSubview:view]) and it somehow finds view controller although view doesn't know its controller.
yeh I had the same question like you. and I figured it out.
UIView is derived from UIResponder. and UIView must subclass UIResponder::nextResponder.
Its default implementation is returning a view controller of the view (if it hadn't, it would be super view)
So, consequently view can see its controller. that means window know the topmost view and also
its controller.
good luck.
Unfortunately, iOS only send events to the first ViewController of the stack. You can try and present a new one on the top of others with video for example, it will never rotate.
If you don't use navbar/tabbar controller you will have to add and remove everytime from the Window to keep only one at the time if you wand to have events.
The main UIWindow class for your application will have a view controller set in its rootViewController property. That controller's view is the "main" view for the app. This is usually setup in the main .xib for the project. That view controller will receive the usual events like "viewDidAppear" or "willRotateToInterfaceOrientation". You can put up your own view over top of it if you want to, but you will need to manage those events yourself. Usually you don't do that though. You just use a UINavigationController or UITabBarController as your rootViewController and allow them to manage getting the events to new "pushed" view controllers, or you popup view controllers with "presentModalViewController".
I have application with multiple UIViewControllers using navigation controller. UIViewController contains tableView, searchbar (that I can show/hide) and toolbar. All of this is added as subviews to its view. All this subviews are created after UIViewController is initialized and their content depend on UIVievController's content.
It works fine expect one problem. When I play with my app a little, move back and forth, open some modal views etc sometimes after navigating back to my root VC all it's subviews dissapear and all I get is white screen.
I double checked all my code and I can't find source of problem (I certainly don't remove them myself). I wasn't able to find exact patern how to reproduce this, it seems random. Any idea why iphone would remove my subviews from VC? I would post some code, but I don't want to put it all here and I am not sure which part is important, so if you wish to see some, let me know
Add your views in loadView or viewDidLoad: when viewDidUnload is called, the view is released, so they need to be created again when the view is shown again.
I'm doing an iPad tech demo and I'm running into a serious technical problem.
I have an app concept that leverages UISplitViewController, but NOT as the primary controller for the entire app.
The app flow could be described roughly as this:
Home screen (UIViewController)
List->Detail "Catalog" (UISplitViewController)
Super Detail Screen (UIViewController but could conceivable also be a child of SplitView).
The problem is in the flow between Home and Catalog. Once a UISplitViewController view is added to the UIWindow, it starts to throw hissy fits.
The problem can be summarized at this:
When a UISplitView generates a popover view, it appears to then be latched to its parent view. Upon removing the UISplitView from the UIWindow subviews, you will get a CoreGraphics exception and the view will fail to be removed.
When adding other views (presumably in this case, the home screen to which you are returning), they do not autorotate, instead, the UISplitView, which has failed to be removed due to a CG exception, continues to respond to the rotation instead, causing horrible rendering bugs that can't be just "dealt with". At this point, adding any views, even re-adding the SplitView, causes a cascade of render bugs.
I then tried simply to leave the SplitView ever present as the "bottom" view, and keeping adding and removing the Home Screen from on top of it, but this fails as SplitView dominates the Orientation change calls, and Home Screen will not rotate, even if you call [homeScreen becomeFirstResponder]
You can't put SplitView into a hierarchy like UINavigationController, you will get an outright runtime error, so that option is off the table. Modals just look bad and are discourages anyway.
My presumption at this moment is that the only proper way to deal with this problem is so somehow "disarm" UISplitViewController so that it can be removed from its parent view without throwing an unhandled exception, but I have no idea how.
If you want to see an app that does exactly what I need to do, check out GILT Groupe in the iPad app store. They pulled it off, but they seem to have programmed an entire custom view transition set.
Help would be greatly appreciated.
Apple states:
The split view controller’s view
should always be installed as the root
view of your application window. You
should never present a split view
inside of a navigation or tab bar
interface.
This does mean it should be root view and not subview of another view. Even though they add:
You should never present a split view inside of a navigation or tab bar interface
That does not mean you can add it as a subview of any other controller either. (sorry)
I have a feeling that what you are experiencing is the byproduct of trying to do so. I am actually surprised that GILT Groupe's app did not get rejected. Apple has a tendency to enforce these HIG guidelines rather strictly lately. They (as you found out already) cause a rather nasty runtime error when you attempt to add them to a NavigationController.
I've solved this for myself... actually worked around... by presenting all other possible full screen views as modals of the SplitView...
This is an unsavory way of doing things in my book, but Apple leaves you little choice if you want to leverage a SplitView only "sometimes" within an app.
I had some success by creating a second UIWindow. I associate the UISplitViewController with that, and switch it out with the main window when I want to show the splitview. It seems to work they way I wanted, except for a slight delay in rotations and a log message about "wait_fences".
Unless your developing for jail-broken devices then bending apples rules/wishes isn't a good idea. Like Jann and Jasconius state above this means keeping a splitView controller view root, not over-using modals (vague) and not using multiple windows.
Also, the Gilt app is only available in the US
I'v been trying to find a solution too and have ended up programatically removing views from the window like Tuannd talks about but the landscape rendering bug is unforgivable.
#Jasconius, What is the max number of modals are you are presenting at any time?
I am struggling with this same issue. I've been trying various things poking at the UISplitViewController as a black box and see how it reacts.
I seem to have come up with a solution to my case which seems to be working satisfactorily.
The key appears to be that the first view added to the UIWindow is the only view properly initialized. All the problems I've had tend to stem from incorrect notification of the orientation of the device. The first view added, apparently has this correctly configured.
In my case I didn't want the UISplitView as the first view. The following is working for me.
The app delegate application:didFinishLaunching method is special. Adding the view to the UIWindow must occur here. If it is done elsewhere it does not get configured properly.
Essentially the magic sauce, is have the split view be the first view added to the window. Its then ok to remove it as long as you retain the UISplitViewController. From then on you can swap other views in and out, including the UISplitView and most things seem to be ok.
I've still run into a few issues. Popovers on views other than the split view are confused on the views frames and location of toolbar buttons and will display in the wrong location. I place then in a specific location and that seems to handle that case.
If a popover on the split view is still displayed, and you try to view another view, the orientation of the second view is confused and shows up sideways. If that view is accessed before the popup is displayed, all is well. I've fixed this my manually dismissing the popover before switching to any other view.
Here's the code if it helps. All the controllers are instance variables of appDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// This also seems to work as good magic. Seems to set orientation and size properties that persist.
[window addSubview:splitViewController.view];
[splitViewController.view removeFromSuperview];
[self switchToNewViewController:firstController];
[window makeKeyAndVisible];
return TRUE;
}
- (void)switchToNewViewController:(UIViewController *)newViewController {
[popoverController dismissPopoverAnimated:FALSE];
if (newViewController != currentViewController) {
[currentViewController removeFromSuperview];
currentViewController = newViewController;
[window addSubView:newViewController.view];
}
}
Just wanted to say that I was running into these same issues, found this forum topic, and followed the advice from g051051 above. This is working perfectly for me. I am not seeing any glitch, and no messages about wait_fences in the console of the device.
I simply used IB to create two UIWindow objects in the main XIB, created as normal the UISplitViewController and then also an instance of my other controller derived from UIViewController (which I am using for full screen display). I have simply hooked them up by attaching the rootViewController for each UIWindow to its appropriate controller.
In application:didLaunch...: method I can decide which window to send the makeKeyAndVisible method and which to set to hidden. When the user want to switch back and forth I simply have to send makeKeyAndVisible to one and set the hidden property on the other, that's all there is to it.
As indicated all of the rotation related messages are sent to each controller appropriately, regardless of which one is associated with the currently visible window.
Anyway, works great for me, and actually quite easy to set up.