I have a view with a custom bar at the bottom of the screen. When a collection view cell is pressed, it loads a detail view, and I can go back.
This all works great; however, I have a plus button displayed on the custom bar, and I would like for the plus button to disappear only when the detail view shows up, and then come back when you hit the back button.
So far I have used the delegate method:
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
// Your code to update the parent view
}
The problem is this fires when the detail view is loaded and popped as well. Any idea on how to accomplish this? Thanks!
I assume mainView and detailView are viewControllers. In mainView's viewWillAppear method
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
//get reference of plus button here
btnPlus.hidden = NO;
}
In detailView's viewWillAppear method
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
//get reference of plus button here
btnPlus.hidden = YES;
}
Related
I'm navigating from a UITableView to a normal ViewController.
I'm displaying the navigationBar like this:
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
[self.navigationController setNavigationBarHidden:NO animated:NO];
}
The first time I hit a row in the UITableView, the navigationBar shows up, but the second time it remains hidden. This is not expected behavior, since viewWillAppear should work every time the view shows up.
Why is the navigationBar hidden when viewing the view for the second time?
This is because you are hiding navigation bar in viewWillAppear of table view. So it will hidden for other pushed view controllers. So in order to get rid of that you have to un hide navigation bar in view did disappear of table view.So it will work in desired manner.
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
self.navigationController.navigationBar.hidden = YES;
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
self.navigationController.navigationBar.hidden = NO;
}
I have implemented a custom version of a search form that behaves a lot like a UISearchBar with a scope bar (but is actually pieced together programatically for UI reasons). The screen loads with a TextField, you tap in the TextField and the navigation bar animates up off the screen, the text field moves up and a segmented control appears for filtering results.
Anyway, that all works, but when I tap on one of the search results my code pushes a new ViewController. The problem is that new controller gets pushed without a navigation bar (because I used [[self navigationController] setNavigationBarHidden:YES animated:YES] when switching to the search state).
I can show the navigation bar as the new ViewController gets pushed, or even animate it in as the transition to the new ViewController appears - but all those solutions look clunky. I want it to work as if you were using a UISearchBar (actually more like the email app) in that the restored navigation bar appears to just slide in from the right as if it's part of the child view controller.
I'm hoping there'll be a simple fix... thanks
For anyone that comes to this, the solution is to make your controller the delegate of the UINavigationController, then show or hide the nav bar in your delegate methods.
Your controller needs to implement the protocol:
#interface MYSearchController() <UINavigationControllerDelegate>
Then in -(void)viewDidLoad assign your controller as the delegate:
[self navigationController].delegate = self;
Finally, implement a method like this:
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
if(viewController == self)
{
if(_searchState && ![self navigationController].navigationBarHidden)
{
[[self navigationController] setNavigationBarHidden:YES animated:YES];
}
}
else
{
if([self navigationController].navigationBarHidden)
{
[[self navigationController] setNavigationBarHidden:NO animated:YES];
}
}
}
I am pushing self view to self.navigationcontroller by allocating. I have a tableView on that view so I am changing the content of tableview. But when I am pressing back button (that is automatically created), I am not able to show previous content. Its showing updated content.
Please suggest.
You set code in viewWillAppear method
- (void)viewWillAppear:(BOOL)animated
{
//code set here
}
If you fill the tableView's data in viewWillAppear: or viewDidAppear:, it will reload even if you only press the back button of your top viewController. If you do not want to have your content changed, you are supposed to use initWithNibName: or viewDidLoad: methoads. They are called only at creation time of the view.
Based on the comments on #Kirti's post, You can check if your viewcontroller is being popped by following method, and take some necessary actions for you controller holding table.
-(void) viewWillDisappear:(BOOL)animated
{
if(![self.navigationController.viewControllers containsObject:self])
{
YourControllerWithTable *instance = [self.navigationController.viewControllers objectAtIndex:self.navigationController.viewControllers.count - 1];
instance.loadOldContent = YES;
}
}
In viewWillAppear: of YourControllerWithTable, you can check:
-(void) viewWillAppear:(BOOL)animated
{
if(loadOldContent)
{
//Do your work here
}
}
You don't push UIView instances onto a UINavigationController instance, only instances of UIViewController.
Hi there, Now I'm trying to create a Pop-OverView using an Xcode
storyboard. Firstly, I have
rootViewController, UIViewController, and UITableViewController
I want the UIView to act as a page flip and the UITableView will show popOver under the navigationBar item controller.
For the UITableView, I want to make a Pop-Over under NavigationBar controller. The problem is, when I touch the Navigation item to show the UITableViewController, it shows correctly, but when I try to close the Pop-Over View, it won't close. And then, the navigation item doesn't work well. It shows multiple instances of popOverView when I touch it multiple times.
This doesn't seem to make sense to me. Can anyone help me out or tell me where to find documentation / tutorials on this?
UPDATE:
For the UIPopOverController, it seems to work well now, but it is still bugging me when I touch a Navigation Item multiple times. It will show multiple instances of PopOver. How can I handle it, so it will show only one instance?
I had the same problem and mostly found the solution here. Basically you change the action of the button each time it's pressed to either display or dismiss the popover. Here's the code I ended up with:
#interface FilterTableViewController : UITableViewController {
UIPopoverController *editPopover;
id saveEditSender;
id saveEditTarget;
SEL saveEditAction;
}
-(void)prepareForSegue:(UIStoryboardPopoverSegue *)segue sender:(id)sender{
if([[segue identifier] isEqualToString:#"EditFilterSegue"]){
// Save the edit button's info so we can restore it
saveEditAction = [sender action];
saveEditTarget = [sender target];
saveEditSender = sender;
// Change the edit button's target to us, and its action to dismiss the popover
[sender setAction:#selector(dismissPopover:)];
[sender setTarget:self];
// Save the popover controller and set ourselves as the its delegate so we can
// restore the button action when this popover is dismissed (this happens when the popover
// is dismissed by tapping outside the view, not by tapping the edit button again)
editPopover = [(UIStoryboardPopoverSegue *)segue popoverController];
editPopover.delegate = (id <UIPopoverControllerDelegate>)self;
}
}
-(void)dismissPopover:(id)sender
{
// Restore the buttons actions before we dismiss the popover
[saveEditSender setAction:saveEditAction];
[saveEditSender setTarget:saveEditTarget];
[editPopover dismissPopoverAnimated:YES];
}
-(BOOL)popoverControllerShouldDismissPopover:(UIPopoverController *)popoverController
{
// A tap occurred outside of the popover.
// Restore the button actions before its dismissed.
[saveEditSender setAction:saveEditAction];
[saveEditSender setTarget:saveEditTarget];
return YES;
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
// Before we navigate away from this view (the back button was pressed)
// remove the edit popover (if it exists).
[self dismissPopover:saveEditSender];
}
I have a tab bar controller with five buttons. That controller has a tab view controller.
The tab view controller should behave differently depending on the tab being pressed.
For example, if the tab is "location", then the displayed data should be sorted based on location. If the tab is "alphabet", then the view should be sorted based on the alphabet.
I have this code in the view controller
-(void)viewWillAppear:(BOOL)animated
{
[super viewDidLoad];
[BNUtilitiesQuick parseXMLFileAtURL:#"http://example.com/BusinessSerialized.xml"];
[BNUtilitiesQuick UtilitiesQuick].BizsToDisplay = [BNUtilitiesQuick searchObjectsInContext:#"Business" :nil :#"Title" :YES];
NSLog(#"%#",[self tabBarController]);
if ([[self tabBarController]selectedIndex]==0)
{
}
NSLog(#"%d",[[self tabBarController] selectedIndex]);
// Do any additional setup after loading the view from its nib.
}
That [[self tabBarController] selectedIndex] works, except for one problem. Rather than giving the current selected index, it's the previous index.
Say I am now selecting tab 0, and I click tab 4; that NSLog() will display 0.
How can I solve this? I want to know the tab being pressed.
By using this delegate method you will be getting your selected index:
# enter code here
- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController
{
NSLog(#"sff %d",tabBarController.selectedIndex);
}