iPhone Navigation Back Button - iphone

I am having issues with the back button not showing up on the SettingsViewController. The navigation bar does show up when the view is pushed, but no back button.
I am creating this inside a view controller, which is not a navigation controller. Any ideas or suggestions on what is actually going on here.
- (void)viewDidLoad
{
self.title = #"Settings";
}
- (IBAction)showSettingsModal:(id)sender
{
SettingsViewController *settingsViewController = [[SettingsViewController alloc] initWithNibName:#"SettingsViewController" bundle:nil];
UINavigationController *navController = [[[UINavigationController alloc] initWithRootViewController:settingsViewController] autorelease];
[self presentModalViewController:navController animated:YES];
[settingsViewController release];
}

You are creating a new navigation stack. You will need to add your own Back button and set the action of that to a delegate method on the calling VC to dismiss it.
UPDATE:
There seems to be lots of confusion about where and how to dismiss ModalViewControllers. The wrong thing to do in most cases is to call the Dismiss method from the Modal VC itself if you are wanting the parent to act on that dismissal. Instead, use delegation. Here is a simple example:
ModalViewController.h:
#protocol ModalViewControllerDelegate
-(void)dismissMyModalVC;
#end
#interface ModalViewController : UIViewController {
id < ModalViewControllerDelegate > delegate;
}
#property (nonatomic, retain) id < ModalViewControllerDelegate > delegate;
// The rest of your class properties, methods here
ModalViewController.m
#synthesize delegate;
...
// Put in the Method you will be calling from that Back button you created
[delegate dismissMyModalVC];
CallingViewController.h:
#import "ModalViewController.h"
#interface CallingViewController : UIViewController
<ModalViewControllerDelegate>
// Rest of class here
CallingViewController.m:
ModalViewController *mvc = [[ModalViewController alloc] initWithNibName:#"ModalViewController" bundle:nil];
mvc.delegate = self
[self presentModalViewController:mvc animated:YES];
...
// The ModalViewController delegate method
-(void)dismissMyModalVC {
// Dismiss the ModalViewController that we instantiated earlier
[self dismissModalViewControllerAnimated:YES];
That way the VC gets dismissed properly from the controller that instantiated it. That delegate method can be modified to pass along objects as well (like when you are finished logging a user in, etc)

SettingsViewController does not have a back button because it is at the bottom of stack. If you want a button to dismiss the modal dialog, you will have to add it yourself.

you can try this
UIBarButtonItem * backButton = [[UIBarButtonItem alloc]initWithTitle:#"Back"style:UIBarButtonItemStylePlain target:self.navigationItem.backBarButtonItem action:#selector(dismissModalViewControllerAnimated:)];

You are presenting your new controller as modal view controller. Modal controller presents its topmost. You should:
[self.navigationController pushViewController:navController animated:YES];
to push view controller onto the stack, and then you will see Back button.
Read Apple documenation on presenting view controllers:
https://developer.apple.com/library/ios/#featuredarticles/ViewControllerPGforiPhoneOS/ModalViewControllers/ModalViewControllers.html
EDIT Didn't see that the calling view controller is not part of the navigation controller. In that case, you will have to create back button manually, and set it as a left bar navigation item.

Related

Use modal view as "normal" view

I want to use a modal view (UIViewController) as a "normal" view, which can be pushed on the navigation controller stack. Normally, a modal view is presented like this:
LoginViewController *myView = [[MyViewController alloc] init];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:myView];
[self.navigationController presentModalViewController:navController animated:YES];
[myView release];
myView = nil;
[navController release];
navController = nil;
But I want to do something like this:
[[self navigationController] pushViewController:myView animated:YES];
The problem is that my modal view has a right and a left button. So I would have to check how the view is loaded and present the buttons in another way. The idea behind this is to have the back button. So I can use the same modal view a few times.
Edit:
#petert:
Now I followed your example. My issue is that I'm using a UINavigationBar for the modal view. To get this UINavigationBar I create a navigation controller. I'm using the navigation bar because I have my buttons in it. So checking if parentViewController is of type UINavigationController does not work for me. I'm always getting a modal view. Here is how I do it:
// load modal view
MyViewController *myView = [[MyViewController alloc] init];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:myView];
[[self navigationController] presentModalViewController:navController animated:YES];
[navController release];
navController = nil;
[myView release];
myView = nil;
// load as normal view
MyViewController *myView = [[MyViewController alloc] init];
[[self navigationController] pushViewController:myView animated:YES];
Good tips in this StackOverflow answer.
I prefer to use UIViewController's property:
#property(nonatomic, readonly) UIViewController *parentViewController
in a view controller's subclass:
Look at the value of the controller's parentViewController property. If it's an instance of UINavigationController, then you're in the navigation stack. If you're being displayed modally, it'll be an instance of your last view controller.
So in -viewDidLoad for example:
- (void)viewDidLoad
{
if ([self.parentViewController isKindOfClass:[UINavigationController class]])
{
// navigation controller
self.title = #"...";
}
else
{
// modal
self.title = #"Modal";
// add cancel and done buttons now...
}
}
Or, a pretty simple solution would be to customize your init method to your MyViewController class to encode your intent for the view controller.
Add the following to the MyViewController header:
#interface MyViewController : UIViewController
{
BOOL modal;
}
- (id)initForModal:(BOOL)isModal;
#end
Now in the implementation file:
#interface MyViewController ()
#property (nonatomic) BOOL modal;
#end
#implementation MyViewController
#synthesize modal;
- (id)initForModal:(BOOL)isModal;
{
if (self = [super initWithNibName:#"MyViewController" bundle:nil])
{
self.modal = isModal;
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
if (self.modal)
{
// add cancel and done buttons …
}
else
{
// assuming we're presented from a navigation view …
}
}
Now to use this modally:
// load modal view
MyViewController *myView = [[MyViewController alloc] initForModal:YES];
Or not modally:
// load as normal view
MyViewController *myView = [[MyViewController alloc] initForModal:NO];
I'm assuming you're creating the view controller(s) from NIBs, but as always see the View Controller Progamming Guide for iOS and especially the section titled "Defining a Custom View Controller Class".
For clarification: myView isn't modal. You just present it as a modal one.
If you just push it into a UINavigationController hierarchy it will behave like a "normal" one.
You can't push the same view controller onto the navigation stack several times. Just once.
Also see this for how to customize the view:
SO modal question

Having a UITabBar AND a UINavigationController in an app?

Hey everyone, I am new to iPhone development and I'm not understanding the whole UINavigationController and UITabBarController idea. Is one a substitute for the other - how do apps such as Tweetie combine both?
I'd like to have my app have a persistent Tab Bar # the bottom (which seems to be working), but also a Navigation bar at the top which can push/pop views onto the screen without removing the tab bar.
How can I accomplish this?
What should the hierarchy look like in IB as far as my MainWindow.xib with regards to all of these controllers?
What is best practice here?
Thanks very much,
Just wrap the view controller inside the UINavigationController and Place the UINavigationController inside the UITabBar.
This will work fine for you…
Example:
NSMutableArray *tabBarViewControllers = [[NSMutableArray alloc] initWithCapacity:2];
tabBarController = [[UITabBarController alloc] init];
[tabBarController setDelegate:self];
UINavigationController *navigationController = nil;
navigationController = [[UINavigationController alloc] initWithRootViewController:<Your View controller1>];
[tabBarViewControllers addObject:navigationController];
[navigationController release];
navigationController = nil;
navigationController = [[UINavigationController alloc] initWithRootViewController:<Your View controller2>];
[tabBarViewControllers addObject:navigationController];
[navigationController release];
navigationController = nil;
tabBarController = tabBarViewControllers;
[tabBarViewControllers release];
tabBarViewControllers = nil;
Use the wizard for a Tab Bar Application, and set it up as normal. In any tab where you want to add a navigation controller, create it in the XIB using the library. My XIB has:
- File's Owner DescriptiveNameNavViewController
- First Responder
- View UIVIew
- Navigation Controller UINavigationController
- Navigation Bar UINavigationBar
Note that there isn't anything in the view. See viewDidLoad below for where the UINavigationController gets attached to the UIView.
In the header file for the Tab's ViewController (which I've here called DescriptiveNameNavViewController -- there isn't a particular standard for this, but I use [Something]NavViewController to remind me that this ViewController contains a navigation controller with the navigation stack. This is the controller name that I set in the MainWindow.xib that the wizard generates) Set up a UINavigationController * IBOutlet that has the navigation controller in the XIB attached to it:
#interface DescriptiveNameNavViewController : UIViewController {
UINavigationController *navigationController;
}
#property (nonatomic, retain) IBOutlet UINavigationController *navigationController;
#end
In the controller for the DescriptiveNameNavViewController , do something like this:
- (void)viewDidLoad {
[super viewDidLoad];
[[self view] addSubview:[navigationController view]];
DescriptiveNameController *aController = [[[DescriptiveNameController alloc ] initWithNibName:#"DescriptiveNameController" bundle:nil ] autorelease];
aController.title = #"Descriptive Title";
//
// app stuff goes here.
//
[self.navigationController pushViewController:aController animated:YES];
[self.navigationController setDelegate:self];
}
Setting the delegate in the DescriptiveNameNavViewController is super-important, because otherwise you won't get the methods called that you expect in DescriptiveNameViewController instances and anything else you push into the navigation controller's stack.
In DescriptiveNameNavViewController, implement the UINavigationControllerDelegate methods like this:
- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
if ([viewController respondsToSelector:#selector(viewDidAppear:)]) {
[viewController viewDidAppear:animated];
}
}
And that will cause messages to get propagated to controllers inside the UINavigationController like you expect. It seems like many problems that people encounter are because the viewDidAppear: or other methods aren't getting called on the ViewControllers pushed into the NavigationController.
Anyway, let me know if more detail would help.

Setting up a Navigation Controller with a Map View in Interface Builder

I'm trying to create a modal view which pops up when the user presses a button. The modal view has a navigation bar with a map view as the main view. I'm having trouble setting this up in Interface Builder. When I set the view outlet for my File's Owner's view to the view inside the Navigation Controller, the only thing that show up is the map view, with a grey space at the top and bottom. The navigation bar never appears. Here's a screenshop of how it looks, with an image of my IB window.
How can I get the navigation bar to show up properly? Thanks
alt text http://img.skitch.com/20100126-d5u4yuufpe77xdkuw2k1h9uahf.jpg
http://img.skitch.com/20100126-xrw6qd5jajytkq5u7x3kdk168s.jpg http://img.skitch.com/20100126-xrw6qd5jajytkq5u7x3kdk168s.jpg
Just in case, here's the MapViewController declaration:
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
#interface MapViewController : UIViewController
{}
#end
And the code to push the modal view controller:
MapViewController *mapVC = [[MapViewController alloc] init];
self.mapViewController = mapVC;
[mapVC release];
[self presentModalViewController:mapViewController animated:YES];
You are going about this the wrong way in your NIB file.
Add the MKMapView to the view of the UIViewController. You could add a navigation bar here instead of a controller if you don't wish this view to go anywhere else.
However, having the navigation controller is very handy. So, ensure that there is no navigation controller in the NIB file for your MapViewController class and then edit your code to look like this:
MapViewController *mapVC = [[MapViewController alloc] init];
self.mapViewController = mapVC;
[mapVC release];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:mapViewController];
[self presentModalViewController:navController animated:YES];
[navController release];
Then you can access this controller from within your MapViewController.m file by using:
self.navigationController

How to switch to next view when button is pressed iPhone?

here is a iPhone programming beginner's question:
How do I get to another view by pressing a button in my main view?
I have the following function which is executed when I press a button, and debugging it, he passes there, but my "Warning" view does not show up:
-(IBAction) showWarningView:(id)sender
{
if(self.showWarning == nil){
WarningViewController *nextView = [[WarningViewController alloc] initWithNibName:#"Warning" bundle:[NSBundle mainBundle]];
self.showWarning = nextView;
[nextView release];
}
[self.navigationController pushViewController:self.showWarning animated:YES];
}
My main RootViewController looks like this:
#import <UIKit/UIKit.h>
#import "WarningViewController.h"
#interface RootViewController : UIViewController {
IBOutlet UIButton *button1;
WarningViewController *showWarning;
}
#property(nonatomic,retain) WarningViewController *showWarning;
-(IBAction) showWarningView:(id)sender;
#end
I am using the navigation control of a UITableViewController but what do I have to use to just simply show my other view when I press a button in a view-based application?
Thanks a lot!
edited
if you're using the navigation control of a UITableViewController, you probably have to push the view in you tableviewcontrollers navigation controller
this means you have pass the navigation controller of your tableviewcontroller on to your viewcontroller, then you just push it
e.g.
[self.tableViewControllersNavigationController pushViewController:self.showWarning animated:YES];
(for passing the tableViewController's navigationController on, you might have to create a delegate pattern)
Does the title in your navigation bar change? Maybe you don't have a UIView associated with your UIViewController inside your Interface Builder file.

Transitioning between subviews in a navigationController?

In my app I have a drill-down type interface as follows:
My root view, which has a list of items and an "Add" button.
Selecting an item pushes the "Detail" view on the navigationController.
Selecting the "Add" button pushes an "Add" view.
How would I transition between the Add view to the Detail view?
I'm thinking of doing an unanimated "pop" on the Add view and push the Detail controller on, but how do I make the second part animated, so the detail view would either slide in vertically or fade in from the Add view?
Thanks,
Kelso
Based on Ramin's reply, you can try this way, which is used by Apple in several samples:
MyListViewController.h
#import "MyAddViewController.h"
#interface MyListViewController : UITableViewController <MyAddViewControllerDelegate> {
}
- (IBAction)add:(id)sender;
#end
MyListViewController.m
// Action for bring up add view controller
- (IBAction)add:(id)sender {
MyAddViewController *addViewController = [[MyAddViewController alloc] initWithStyle:UITableViewStyleGrouped];
addViewController.delegate = self;
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:addViewController];
[self presentModalViewController:navigationController animated:YES];
[navigationController release];
[addViewController release];
}
// MyAddViewController's delegate method, dismiss the add view controller in here
- (void)addViewController:(MyAddViewController *)addViewController didAddData:(MyData *)data{
if (data) {
MyDetailViewController *detailViewController = [[MyDetailViewController alloc] initWithStyle:UITableViewStylePlain];
detailViewController.data = data;
[self.navigationController pushViewController:detailViewController animated:YES];
[detailViewController release];
}
[self dismissModalViewControllerAnimated:YES];
}
MyAddViewController.h
#protocol MyAddViewControllerDelegate;
#class MyData;
#interface MCCourseAddTableViewController : UITableViewController {
#private
MyData *data;
id <MCCourseAddDelegate> delegate;
}
// MyData could be NSManagedObject if you want to use Core Data
#property(nonatomic, retain) MyData *data;
#property(nonatomic, assign) id <MyAddViewControllerDelegate> delegate;
- (void)save;
- (void)cancel;
#end
#protocol MyAddViewControllerDelegate <NSObject>
#optional
- (void)addViewController:(MyAddViewController *)addViewController didAddData:(MyData *)data;;
#end
MyAddViewController.m
- (void)save {
if (self.delegate != nil) {
if ([self.delegate conformsToProtocol:#protocol(MyAddViewControllerDelegate)]){
if ([self.delegate respondsToSelector:#selector(addViewController:didAddData:)]){
// Send data back to List View, to bring up detail view controller and dismiss add view controller
[self.delegate addViewController:self didAddData:self.data];
}
}
}
}
- (void)cancel {
if (self.delegate != nil) {
if ([self.delegate conformsToProtocol:#protocol(MyAddViewControllerDelegate)]){
if ([self.delegate respondsToSelector:#selector(addViewController:didAddData:)]){
// Send nil back to ListView, to dismiss the add view controller only
[self.delegate addViewController:self didAddData:nil];
}
}
}
}
You could push the Add View onto the Details view and set a variable to remember that.
When the user try to pop the Add View, you check the previous variable and, if set, you pop directly to the root controller(that should pop the Details view automatically).
Marco
Make the add view a modal and in there provide a "Done" (or "Save") and a "Cancel" button. If the user hits cancel, you just close the modal. If they hit Done you save the new record to the table model, then do a table reload on the root view before returning. To be nice, you can flash the newly added item.
A clean way to set this up is to make the modal controller implement a delegate that expects a 'Done' protocol method and have the root controller implement it and set itself as the delegate.
This way, the root controller is notified when the user hits 'Done' so it can encapsulate all that needs to happen. If you want to go directly from add to detail view the delegate method can do a 'push' for the newly added record and you'll get a nice transition from modal sliding down to detail view.