Rotation affecting Navigation Bar unpredictably - iphone

Here is my setup: one navigation controller, two views
The first view, the rootview, displays the statusbar and navigation bar (portrait view).
When the rootviewController senses rotation, it hides the nav bar and status bar and then it pushes view 2 onto the navigation controller (in landscape now).
This part works as expected.
When View2 viewcontroller senses rotation (back to portrait), it pops itself of the navigation controller, revealing view 1. View 1 then unhides the status bar and nav bar.
From here, it gets weird. Depending on when I unhide the navigation bar, I get strange results. As you can see below (The beaker photo should be just below the navbar at the top of the screen).
I have tried unhiding the navigation bar in:
viewWillRotate/viewDidRotate of view 2
viewWillAppear/viewDidAppear of view 1
poptoRootView in the navigation controller (I subclassed just to try)
Nothing works. Any Idea what is going on? This should be simple, but maybe I am doing things in the wrong places.

Check your autoresizing mask on all views in your nib and make sure its all set properly. If you have anything the way its not supposed to be it will freak out on rotation.

Not sure why it's necessary, but when you're swaping views, you must apply a transformation to your view (with only 1 view the iPhone does this for you), and you must set the bounds of it.
Here is the code that should work for you (on the willAnimateFirstHalfOfRotationToInterfaceOrientation):
#define degreesToRadians(x) (M_PI * (x) / 180.0)
if (UIInterfaceOrientationIsLandscape(toInterfaceOrientation)) {
self.view = landscapeView;
self.view.transform = CGAffineTransformIdentity;
self.view.transform = CGAffineTransformMakeRotation(degreesToRadians(90));
self.view.bounds = CGRectMake(0.0, 0.0, 480.0, 320);
} else {
self.view = portraitView;
self.view.transform = CGAffineTransformIdentity;
self.view.transform = CGAffineTransformMakeRotation(degreesToRadians(0));
self.view.bounds = CGRectMake(0.0, 0.0, 300, 480);
}

In the end, I reworked my app. (to use a modal view controller)
But I came into similar issues, instead white space where the status bar was located.
I think both problems can be attributed to not talking to the Navigation Controller when rotating/resizing views (instead I was talking to the ViewController.
For details of how I solved the problem:
iPhone + CGAffineTransFormRotate(pi/2) + statusBarHidden:YES + presentModalViewController = 20 pixels of white space

Related

How to have tabBar animate in after the view is fully pushed into view?

I am trying to emulate the way TweetBot/NetBot animates the tabBar in after a push from the tableView of Accounts action. When the view is fully pushed, only then does the taBar animate in from the bottom. I have tried all sorts of hide/show methods and all seem to fail when it comes to the "show" part.
Does anyone have a suggestion as to how this can be done?
First of all, I presume you are not using a UITabViewController since it cannot be pushed into a UINavigationController stack, so I think you are using a standalone UITabBar embedded in a UIViewController. Is this assumption right?
Try with this code (I didn't try it).
- (void)viewDidAppear {
[super viewDidAppear];
// Calls showTabBar method after SOME_DELAY. You can also call directly [self showTabBar] if you want zero delay.
[self performSelector:#selector(showTabBar) afterDelay:SOME_DELAY];
}
- (void)showTabBar {
// Before the animation begins, your UITabBar must be outside the view controller's view frame.
CGRect tabBarFrame = CGRectMake(0,
CGRectGetHeight(self.view.bounds),
CGRectGetWidth(self.view.bounds),
CGRectGetHeight(self.tabBar.frame);
self.tabBar.frame = tabBarFrame;
// Let's start with the animation, setting a new frame for tab bar inside an animation block
[UIView animateWithDuration:ANIMATION_DURATION animations:^{
// Change origin Y. It assumes that the height of self.tabBar is right, otherwise put the height you want instead of CGRectGetHeight(self.tabBar.frame).
tabBarFrame.origin.y = CGRectGetHeight(self.view.bounds) - CGRectGetHeight(self.tabBar.frame);
self.tabBar.frame = tabBarFrame;
}];
}

UINavigationController and Alternate Landscape

In my application I use an Alternate Landscape Interface strategy (present your landscape view as a modal). I also use a navigation controller for transitioning and this causes the following problem: I dunno how to push/pop correctly from landscape orientation.
I came up with the following solution, but someone may know a better one. Suppose one has to deal with only two views. Let's call them AP, AL, BP, BL, where the second letter stands for orientation. We start with a navigation controller with AP inside. To go between AP and BP we just push/pop. To go from AP to AL we present a modal navigation controller with AL inside. To go between AL and BL we push/pop inside the second navigation controller. Now to go from BP to BL we pop w/o animation and present a modal navigation controller with BL sitting on top of AL. To go from BL to BP we dismiss the modal navigation controller and push BP w/o animation.
Seems to be a bit ugly, but not so bad. Can anyone think of something better?
Thanks in advance!
Is there some reason you need to present your landscape orientation as modal in a separate controller? When I have two entirely different views for my portrait and landscape orientations I fade between them as they stretch during the rotation.
This allows for vastly different content in both orientations, a nice transition between them, and shared code under one controller.
Here is some code. Our UIViewController will switch between portraitView and landscapeView when we change orientation.
portraitView and landscapeView are both children of the UIViewController's view. The hierarchy looks as follows:
UIViewController
|
- view
|
|- portraitView
|
|- landscapeView
Both have their autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight to ensure that they stretch as the view controller rotates.
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
if( orientation == UIInterfaceOrientationLandscapeLeft || orientation == UIInterfaceOrientationLandscapeRight )
{
[UIView animateWithDuration:duration
animations:^
{
//Fade the landscape view over the top of the
//portrait view as during rotation
landscapeView.alpha = 1.0f;
}
completion:^(BOOL finished)
{
//Hide the portrait view when landscape is fully
//visible
portraitView.alpha = 0.0f
}];
}
else
{
//Show the portrait view (underneath the landscape view)
portraitView.alpha = 1.0f;
[UIView animateWithDuration:duration
animations:^
{
//Fade out the landscape view to reveal the portrait view
landscapeView.alpha = 0.0f;
}];
}
}
Your controls and subviews will fade and deactivate along with the appropriate views, allowing you to have completely different content. I used this recently to fade between two different background images when changing orientation. The effect is very smooth.
You can now create your two view controllers, A and B which each manage two views as described above. You can then simply push the view controllers as normal and not have to worry about managing the UINavigationController's view controller stack during rotation.

Rotating view leaves 20 pixel gap on one side

I have a child view controller that needs to be always shown in landscape mode regardless of which mode the parent view is in. I'm adding it onto the parent's view stack with
[[self navigationController] pushViewController:controller animated:NO];
I am trying to force the view to rotate and be displayed as if the device is held in Landscape orientation even though it's still held in Portrait orientation.
The only problem is that no matter what size and coordinates I set the view frame to, I see a 20 pixel gap on the right side of the screen where the StatusBar used to be during Portrait Mode.
What can I adjust to ensure that this gap is gone?
Here's how I'm doing the transformation (as recommended by this SO article)
- (void)changeOrientationToLandscape
{
UIApplication *myApp = [UIApplication sharedApplication];
CGAffineTransform landscapeTransform = CGAffineTransformMakeRotation( degreesToRadian(90) );
landscapeTransform = CGAffineTransformTranslate(landscapeTransform, +90.0, +90.0 );
[self.view setTransform:landscapeTransform];
// Change the status bar orientation so it's shown as if we're in landscape
myApp.statusBarOrientation = UIInterfaceOrientationLandscapeLeft;
// Manually force view frame - this doesn't seem to fix the 20 pixel gap
self.view.frame = CGRectMake(0, 0, 480, 320);
}
The only time I see the view taking up the entire screen and without the 20 pixel gap is if I hide the status bar all together, something I cannot do for this app.
Here's how the screen looks (it's held in Portrait orientation with the home button on the bottom). Notice how the status bar ends doesn't have the same purple background - I was hoping I could shift the view over so the white gap is no longer present.
I also printed out the view and navigationController's view frames and they both report
x and y location at 0,0. The navigation view frame's reported dimension is 320x480 while view's frame is 480x320.
What about disabling the status bar when child is pushed and enabling when it's "popped"?
You can hide status bar for your child view controller only.
If you're pushing your child view controller via self.navigationController, simply override shouldAutorotateToInterfaceOrientation in child view controller and put this ...
return UIInterfaceOrientationIsLandscape( interfaceOrientation );
... to body of this method to make it landscape only.

iPhone's UITabBar as part of application window; problems when rotating device

I have an iPhone application that's using Navigation Controller to display the top bar (with title and back button, and such...).
I added a UITabBar to the application window, that enables to switch between the parts of it. Instead of adding the tab bar to each of ViewController's view I added the bar to app window.
(When I had it in the ViewController, switching between controllers made the tab bar to swipe left/right, when animated pop/push occured, together with whole view).
So, I added the UITabBar to the MainWindow.xib, and tied it to the app delegate's variable. In my didFinishLaunchingWithOptions method, I added the following code:
[self.window addSubview:navigationController.view];
CGRect frame = navigationController.view.frame;
frame.size.height -= tabbar.frame.size.height;
navigationController.view.frame = frame;
tabbar.selectedItem = [tabbar.items objectAtIndex:0];
to resize the main (navigationController's) view, in order to make the TabBar visible.
The problem shows up when I rotate the device -- my view gets stretched to full window and I loose the ability to show the TabBar.
I added a - (void) didRotateFromInterfaceOrientation:(UIInterfaceOrientation) fromInterfaceOrientation method to my ViewController, with the following code:
- (void) didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation {
CGRect frame = self.view.frame;
frame.size.height -= [AppState shared].tabBar.frame.size.height;
//frame.origin.y = [AppState shared].tabBar.frame.size.height;
//frame.origin.x = 100;
self.view.frame = frame;
frame = [AppState shared].tabBar.frame;
frame.origin.y = [UIScreen mainScreen].bounds.size.height - frame.origin.y - frame.size.height;
[AppState shared].tabBar.frame = frame;
}
It resizes the view, and moves the tab bar to up/down part of the view (I allow only Portrait/Portrait upside down orientations here). The problem is, my TabBar is turned upside down as well, and also, it's no longer clickable.
It looks like the image below:
Anyone knows how to handle this kind of situation? Or, how to make the tab bar not tied to view controller, but also able to handle interface's rotation smoothly?
You are using the tabbar in an unintended way. You seem to be using the UITabBarView as an uncontrolled element of other views. That is not it's function.
The UITabBarView should be controlled directly by a UITabBarController which in turn should be controlling all the view controllers for the views displayed in the tabbar i.e. the tabbar controller is a type of navigation controller that controls subcontrollers.
Suppose you have three tabs and the third one is a navigation controller. Your controller hierarchy would look like this:
TabbarController:
-->tab1ViewController
-->tab2ViewController
-->tab3ViewController(UINavigationController):
-->rootViewController-->secondViewController
You are trying to move and manage the tabbar view without its controller and the proper controller hierarchy. That isn't going to work.

iOS -- how do you control the size of a modal view controller?

I am presenting a modal view controller. If it matters, it is scrolling up from the bottom. How can I control what portion of the screen it occupies?
EDIT: I have the following in the modal view controller. It's not helping.
- (void)viewDidLoad {
TestResultView *trv = [[TestResultView alloc]initWithTest: [Model m].currentTest];
self.view = trv;
trv.frame = CGRectMake(0, 320, 320, 160);
[trv release];
[super viewDidLoad];
}
You can modify the frame of the view controller, but if you're using UIViewController's -presentModalViewController:animated: method, the view behind will be unloaded once your modal view is finished animating onto the screen (This assumes you're on an iPhone) and you'll see a white screen where your background view should be. iOS assumes that your modal view controller will be a full-screen view controller, and dumps the other view to save memory.
If you really want to show a view over part of the screen, you should instead add the UIView (no UIViewController) to your current UIViewController's view as a subview, and then animate it onscreen yourself. I think something like this would work in your UIViewController class that will present the view:
// Add the view as a subview and position it offscreen just below the current view
UIView *myHalfView = [[UIView alloc] initWithFrame:someAppropriateFrame];
[self.view addSubview:myHalfView];
CGRect offScreenFrame = myHalfView.bounds;
offScreenFrame.origin = CGPointMake(0.0, CGRectGetMaxY(self.view.frame));
// Now animate the view upwards
[UIView beginAnimations:nil context:nil];
// Move the view upwards the height of your sliding view so it's entirely onscreen
myHalfView.center = CGPointMake(myHalfView.center.x, myHalfView.center.y - myHalfView.bounds.size.height);
[UIView commitAnimations];
[myHalfView release];
For bonus points, you could fade the view in by setting
myHalfView.alpha = 0.0;
before the UIView animation block, and setting
myHalfView.alpha = 1.0;
inside the block after animating the center property.
When you're done, you can do something similar but in reverse to slide the view offscreen. You can add an animationDidStop selector to the UIView animation block to be notified when the view has slid off screen so that you can remove it from the view hierarchy.
From an aesthetic point of view, you should also be careful how you do this since having a view slide up is a standard behavior, and if your view looks like a normal view but stops halfway, users may feel (even briefly) that the app has frozen. They'll figure it out, but it will leave a bad feeling about your app if not handled carefully. Mainly, I would avoid using standard full-screen cues like including a UINavigationController at the top of your view to help users understand what's going on. Half-sheets tend to be UIActionSheets on the iPhone, so think in that direction.
That is nice, the above accepted answer explains a nice hack to present subViews which feel like ModalViews, but what if it is an iPad, and i can indeed give it a modalViewController which doesnt cover the entire screen.
In case of iPads, I dont think the underneath view will be unloaded. ( because there are options where we can present the modalView on iPads, which dont cover the entire screen )
ModalViewController in the end is a controller itself, and like any other controller has a root view, whose properties can be editted, if we can get hold of it.
Here is what will give you a custom frame of the ModalView :
MyViewController *viewController = [[MyViewController alloc] init];
viewConroller.modalPresentationStyle = UIModalPresentationFormSheet;
[self presentModalViewController:viewController animated:YES];
//superView of viewController's view is modalViewController's view, which we were after
viewController.view.superview.frame = CGRectMake(x,y,w,h);
//x y w h - can have desired values.
I would add to #dsaw's answer that the superview of the modal view does not seem to rotate its coordinate system in landscape mode. Here is the code that I used in my own app:
MyViewController* modalVC = [[MyViewController alloc] init];
modalVC.modalPresentationStyle = UIModalPresentationFormSheet;
[self presentModalViewController:modalVC animated:NO];
CGRect r = CGRectMake(self.view.bounds.size.width/2 - 236,
self.view.bounds.size.height/2 - 130,
472, 260);
r = [self.view convertRect:r toView:modalVC.view.superview.superview];
modalVC.view.superview.frame = r;
While the superview may not rotate itself with the iPad, it does seem to do the right thing and keep the modal view centered if I rotate the iPad after showing the modal view.