I have a navigation based app. The first view (rootcontroller) starts with three large buttons only. No navigationbar. From there, everything else is tableviews and have navigation bars. I'm doing this to show/hide the navigation bar:
MyAppAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
appDelegate.navigationController.navigationBar.hidden = NO;
Once I leave the root controller, the navigation bar will jerk into place and lay on top of the tableview, rather than pushing it down. It clips the top part of the tableview. Going back to the root controller isn't smooth in how the navigation bar disappears. Is there a smoother/better way to do accomplish hiding the navigation bar for the root controller only?
You can use [navigationController setNavigationBarHidden:YES animated:YES] to hide the bar smoothly.
Reference
This nifty bit of code animates the navigation bar hiding with no UI issues:
[navigationController setNavigationBarHidden: YES animated:YES]
But...
Use the self.navigationController.navigationBarHidden property for checks in the code instead of the self.navigationController.navigationBar.hidden property. This will save you a lot of pain from unexpected UI positioning problems.
Take care to place this method in - (void)viewWillAppear:(BOOL)animated or later in the view lifecycle. This is recommended because if you do it in - (void)viewDidLoad for instance, you will get an ugly black rectangular view during animations from a view which displays its navigation bar to a view which doesn't!
For example, if your home view has its navigation bar hidden but all its children have the navigation bar shown, when you pop to home view, the animation will show a black bar in place of the navigation bar until the animation completes
You can customize the navigation bar animation and duration by the following methods. It will provide you callback once animation will be completed.
// pass a param to describe the state change, an animated flag and a completion block matching UIView animations completion
- (void)setNavigationBarVisible:(BOOL)visible animated:(BOOL)animated completion:(void (^)(BOOL))completion {
// fail if the current state matches the desired state
if ([self navigationBarIsVisible] == visible) return completion(YES);
// get a frame calculation ready
CGFloat nheight = self.navigationController.navigationBar.frame.size.height;
CGFloat noffsetY = (visible)? -nheight : nheight;
// zero duration means no animation
CGFloat duration = (animated)? 0.3 : 0.0;
[UIView animateWithDuration:duration animations:^{
CGRect nframe = self.navigationController.navigationBar.frame;
self.navigationController.navigationBar.frame = CGRectOffset(nframe, 0, noffsetY);
} completion:completion];
}
// know the current state of the navigation bar
- (BOOL)navigationBarIsVisible {
return self.navigationController.navigationBar.frame.origin.y < CGRectGetMinY(self.view.frame);
}
// Show or Hide navigation bar
[self setNavigationBarVisible:![self navigationBarIsVisible] animated:YES completion:^(BOOL finished) {
NSLog(#"navigation bar finished");
}];
Before hide a Navigation bar:
After hide a Navigation bar:
Related
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;
}];
}
I want a global navigation stack. When the user changes tabs or navigates to a new view in the same tab, I want to push the new view onto the global navigation stack. I want the back button in the navigation bar to go back to the previous view, which is sometimes a different tab, and sometimes a different view in the same tab.
To achieve this effect, you could ditch the UITabBarController - and emulate the bar by using a custom view or customizing the standard UIToolbar.
Have one navigation controller with, with your customized toolbar always visible, and when buttons are tapped on it, just push the views you want onto the navstack.
You want all the UIViewController's in the UITabBarController to be loaded into the same UINavigationController?
So something like this:
___ RootViewController ___
| |
UINavigationController UITabBarViewController
instead of
RootViewController
|
_________ UITabbarViewController _____________________
| | |
UINavigationController UINavigationController UINavigationController
You should try "experimenting" with your own custom UITabBar
I suggest you to create a global array (NSMutableArray) that will hold NSInvocation objects. So every time you push view controller you need to create NSInvocation with navigation controller as target and popViewConrollerAnimated: as selector. If you're tapping the tab bar item you need to set tab bar controller as target and setSelectedViewController: as selector. You should also specify current view controller as parameter using
- (void)setArgument:(void *)buffer atIndex:(NSInteger)index
Then every time you pop your global stack you need just call [myLastInvocation invoke];
I Had similar issue. I did it like this :
To change the tab, use : say, you want to go at tab 2 and its 3rd view controller
self.tabBarController.selectedIndex = 2;
[self.tabBarController.delegate tabBarController:self.tabBarController didSelectViewController:
[[[self.tabBarController.viewControllers objectAtIndex:2] viewControllers] objectAtIndex:3]];
you could achieve the same by setting the left bar button of your UINavigationController as the button of your choice, Handle the action method and invoke the appropriate tabbar button on click event.
You need to do all that in your root view controller ...
ADDED:
You could not get the back button on the root view controllers (Navigation controllers;s root view associated with your tabbar instance) just by pressing the tabbar button.
you need to find the way to achieve this as you are not getting this from iOS So The movement you press the tabbar button your need to have the variable that store the previous selected index and a method that give the information for any tabbar by just passing the index ... So by using these two you could set the title of your left bar button of navigation bar and return to the previous tab by assigning the appropriate action method to the left bar button ...
I got it working. In my experience I was needed to have mainTabBarController and detailedNavigationController as two root controllers.
Those two methods of UIApplicationDelegate class work perfect:
- (void) showDetailedTab
{
CGRect normalRect = self.window.bounds;
CGRect rightRect = CGRectOffset(normalRect, normalRect.size.width, 0);
CGRect leftRect = CGRectOffset(normalRect, -normalRect.size.width, 0);
detailedNavigationController.view.frame = rightRect;
mainTabBarController.view.frame = normalRect;
[self.window addSubview:mainTabBarController.view];
[self.window addSubview:detailedNavigationController.view];
[UIView animateWithDuration:0.35 delay:0.0 options:UIViewAnimationCurveEaseOut
animations: ^{
detailedNavigationController.view.frame = normalRect;
mainTabBarController.view.frame = leftRect;
}
completion: ^(BOOL finished){
[mainTabBarController.view removeFromSuperview];
}];
}
- (void) showMainTabBar
{
CGRect normalRect = self.window.bounds;
CGRect rightRect = CGRectOffset(normalRect, normalRect.size.width, 0);
CGRect leftRect = CGRectOffset(normalRect, -normalRect.size.width, 0);
mainTabBarController.view.frame = leftRect;
detailedNavigationController.view.frame = normalRect;
[self.window addSubview:mainTabBarController.view];
[self.window addSubview:detailedNavigationController.view];
[UIView animateWithDuration:0.35 delay:0.0 options:UIViewAnimationCurveEaseOut
animations: ^{
mainTabBarController.view.frame = normalRect;
detailedNavigationController.view.frame = rightRect;
}
completion: ^(BOOL finished){
[detailedNavigationController.view removeFromSuperview];
}];
}
I think this solution is better then emulating of tab bar, since it doesn't break UIViewContoller's life cycle.
I just want to enable/disable the status bar per view controller (some view full screen, some not)
I've been several times through all the post related to the status bar 20 pixels issue, but still have the problem, especially on iOS5.0 (some trick worked on older iOS version):
Here is the problem definition:
I use [[UIApplication sharedApplication] setStatusBarHidden:YES] to hide the status bar
I always have the 20 pixel height white empty area if I do this
I've try to enable/disable the navigation bar to force a layout, this does not works on iOS 5:
[self.navigationController setNavigationBarHidden:NO animated:NO];
[self.navigationController setNavigationBarHidden:YES animated:NO];
I've try to manually reset the view frame size, no change
self.view.frame=CGRectMake(0, 0, 320, 480);
I've tried to change manually the navigation container view:
self.navigationController.frame=CGRectMake(0, 0, 320, 480);
All the view are of course 480 pixels height
Use the following method in viewWillAppear of view controller to which you would like to display StatusBar.
[[UIApplication sharedApplication]setStatusBarHidden:YES];
Declare one BOOL variable to indicate whether status bar is hidden or not while view is loaded in view controller which you would like to hide status bar and set its value to NO.
BOOL statusBarHidden = NO;
Then add the following code in viewWillAppear of view controller(Status Bar is hidden in this view)
[[UIApplication sharedApplication] setStatusBarHidden:YES];
if(statusBarHidden == NO)
{
self.navigationController.navigationBar.frame = CGRectOffset(self.navigationController.navigationBar.frame, 0.0, -20.0);
statusBarHidden = YES;
}
I think, You want to hide Status Bar andSet the ViewControllers In Full Screen With Navigation Bar then use
[self.navigationController.view setNeedsLayout];
other method use in you want to hide status Bar....
[[UIApplication sharedApplication]setStatusBarHidden:YES withAnimation:NO];
[self wantsFullScreenLayout];
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.
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.