I am trying (from my 3rd child in the heirachy) to load the root view with the following. This does not work and I get the following error when the below code is run.
-[DetailViewController clickButton:]: unrecognized selector sent to instance 0x1161e00'
Code:
MapViewController *dvController = [[MapViewController alloc] initWithNibName:#"MapView" bundle:[NSBundle mainBundle]];
[self.navigationController pushViewController:dvController animated:YES];
[dvController release];
dvController = nil;
This exact same code works on other views, any idea how to debug this.
The code you wrote to create the MapViewController and push it onto the view controller stack is correct.
The unrecognized selector error is telling you that you are sending are attempting to call a method (named clickButton:) that does not exist.
I would suspect a spelling error. I take it that you most likely have a button defined that calls the code to create the new view. The method should look like this:
-(void) clickButton: (id) sender {
MapViewController *dvController = [[MapViewController alloc] initWithNibName:#"MapView" bundle:[NSBundle mainBundle]];
[self.navigationController pushViewController:dvController animated:YES];
[dvController release];
dvController = nil;
}
I would check that you have the ":(id) sender" part. I have made the mistake before of implementing a -(void) clickButton {} method, but had the message actually sending a parameter as well.
If you have created the button programatically and set the target as clickButton, make sure the clickButton method is present
The clickButton method (according to the error) should take in an argument. So the definition of the method will be
(IBAction)clickButton:(id)sender;
If you have mapped the IBAction to an event in IB, you can omit the :(id)sender part
To load the root view controller from any view in a navigation-based application, use
[[self navigationController:popToRootViewControllerAnimated:YES];
Related
I would like to know a method for navigating from one page to another page onclick .I
have tried
[self.navigationController
pushViewController:self
.objectNewlist
animated:YES];
but it is showing the error
Incompatible pointer types sending 'newlistplist *' to parameter of type 'UIViewController *'
my main class file is a subclass of UIViewController
and the second class is a subclass of UITableViewController
can any one help me out with this problem?
You can use
UIViewController *yourViewController = [[YourViewControllerClass alloc] initWithNibName:#"<name of xib>" bundle:nil];
[self presentModalViewController:yourViewController animated:YES];
[yourViewController release];
In case the new view is also to be created programmatically, you can do that in the viewDidLoad method of YourViewControllerClass and change the initialization to
UIViewController *yourViewController = [[YourViewControllerClass alloc] init];
In YourViewController when you wish to come back to previous view on some button action you can use
[self dismissModalViewControllerAnimated:YES];
Another way that you can do is
UIViewController *yourViewController = [[YourViewControllerClass alloc] init];
[self addSubview:[yourViewController view]];
and to remove the view you can use
[self.view removeFromSuperview];
-(void)onClickButton
{
ViewControllerClass *objViewControllerClass = [ViewControllerClass alloc] init] ;
[self presentModalViewController:objViewControllerClass animated:YES];
[objViewControllerClass release];
}
objViewControllerClass (object of another class)
I founded that the problem is the place where I'm calling the showNextView. I have another interface webService where i communicate with server and parse xml. When the parsing is finished with method parserDidEndDocument I'm calling the delegate method where is changed the view and show modal view. But when i call all that methods it will return to endDocument and xmlParseChunk and so on. It looks like the parserDidEndDocument is not realy the last method and somehow it mess with navigationcontroler. When i call the method for showig nextView with button it works.
The code which is working on button. In delegate method called from parserDidEndDocument is not working correct.
-(void)showNextView
{
UIViewController *nextView = [self.storyboard instantiateViewControllerWithIdentifier:#"vcTrabantInfo"];
[[nextView navigationController] setNavigationBarHidden:NO animated:NO];
[[self navigationController] pushViewController:nextView animated:YES];
UIViewController *picker = [[UIViewController alloc] init];
[picker setModalPresentationStyle:UIModalPresentationFormSheet];
[[self navigationController] presentModalViewController:picker animated:YES];
}
As usualy the problem was between keyboard and seat. The problem was that my modal views haven't been dismissed before i call another modal view :). So keep in mind that all is done in viewDidDisappear.
So I want a RootViewController that can handle a different view controller for each cell (Okay, I have my reasons not to reuse nibs here).
I can list them all up in the didSelectRowAtIndexPath like this:
if(condition){
DetailViewController *dvController = [[DetailViewController alloc] initWithNibName:#"DetailViewController"
bundle:[NSBundle mainBundle]];
dvController.selectedCountry = selectedCountry;
[self.navigationController pushViewController:dvController animated:YES];
[dvController release];
}
else if (condition2){
DetailViewController2 *dvController2 = [[DetailViewController2 alloc] initWithNibName:#"DetailViewController2"
bundle:[NSBundle mainBundle]];
dvController2.selectedCountry = selectedCountry;
[self.navigationController pushViewController:dvController2 animated:YES];
[dvController2 release];
dvController2 = nil;
}
but that can be quite long and I don't know any other way to do it. Are there some sort of "special controllers" or classes that I can use to address this? I am new to iOS development so I know just a little of it.
Thanks in advance!
I think you can use a Factory Method returning an object of UIViewController as that is the argument type of pushViewController (as you can see in the API docs for UINavigationController). Basically you create a method expecting an int,String,Enum to tell what kind of DetailView you want to create, then it creates an object of the given DetailView implementation and returns it. Then you can push that new controller using pushViewController.
I have a simple app with only location services and 3 (almost empty) different views, and from some reason I can't get from view 1 to view 2 - app crashes and I get an exception. View 1 is the original .xib file, the two others are just views that I added later. It's weird cause I can switch between all of them (1->3, 2->1, 2->3, etc..) just not from 1->2.
I use this code in #1 view controller m. file:
- (IBAction) switchToMaps : (id)sender //this is the one that doesnt work
{
MyMap *mapsView = [[MyMap alloc] initWithNibName:nil bundle:nil];
[self presentModalViewController:mapsView animated:YES];
}
- (IBAction) switchToThird : (id)sender
{
ThirdView *third = [[ThirdView alloc] initWithNibName:nil bundle:nil];
[self presentModalViewController:third animated:YES];
}
and as another example, here is the code from the 2nd view controller (MyMaps.m):
- (IBAction) switchBack : (id)sender
{
LastLocationViewController *firstView = [[LastLocationViewController alloc] initWithNibName:nil bundle:nil];
[self presentModalViewController:firstView animated:YES];
}
- (IBAction) switchFront : (id)sender
{
ThirdView *lastView = [[ThirdView alloc] initWithNibName:nil bundle:nil];
[self presentModalViewController:lastView animated:YES];
}
I know it's super vague, but any ideas what can cause this? I have no idea how to debug this...I even put breakpoints at the beginning of each IBAction method, and when it crashes, it doesnt even stop there....before I added this code, this app (which has only location) worked totally fine.
Any ideas?? Thanks!!
if your view does not load from any nib file then you should do like
MyMap *mapsView = [[MyMap alloc] init];
and
ThirdView *lastView = [[ThirdView alloc] init];
and in your back method
- (IBAction) switchBack : (id)sender
{
// LastLocationViewController *firstView = [[LastLocationViewController alloc] initWithNibName:nil bundle:nil]; // because you are allocating new memory to your last view
// [self presentModalViewController:firstView animated:YES];
[self dismissModalViewControllerAnimated:YES];
}
- (IBAction) switchFront : (id)sender
{
// ThirdView *lastView = [[ThirdView alloc] initWithNibName:nil bundle:nil];
// [self presentModalViewController:lastView animated:YES];
[self dismissModalViewControllerAnimated:YES];
}
My hunch is that you're throwing an exception because
MyMap *mapsView = [[MyMap alloc] initWithNibName:nil bundle:nil];
is failing to load a nib. Without seeing your console output it's impossible to say for sure. So a few things to try:
Comment out [self presentModalViewController:mapsView animated:YES];, see if it still crashes.
Explicitly name the nib you expect to load. The nib loader assumes the nib is named exactly the same as the view controller if you pass in nil. So if you don't have a match, you'll end up with an exception (Like this [[MyMap alloc] initWithNibName:#"NibNameWithoutExtension" bundle:nil];)
Set a breakpoint at [self present... and then hover your mouse over "mapsView" after execution pauses. If the popup thing shows you mapsView is nil, you know your trouble is trying to pass a nil object to -presentModalViewController:animated:. If your breakpoint never hits because you throw an exception first, well, there you go, the trouble is a line above.
edit:
One more thing. If your nib has a button that's wired to an action that no longer exists, that would definitely get you in trouble. Inspect each button and make sure no actions are labeled in yellow, indicating a mismatch between the button's target and the actions it's reporting to IB. This would definitely account for the breakpoint behavior you described.
I am just starting with iPhone programming. I used the utility application project template. A button on the main view of the utility application calls another view which shows some data. At the end of the presentation of the data a "end" view is shown. The "end" view contains a button to return to the main view. This all works great, however once you return to the mainview and try either to click the info button or click the button to call the data view the application terminates with the following error:
-[TheEVController startS]: unrecognized selector sent to instance 0x3933d90
EVController.m
- (IBAction)done {
EVController *controller = [[EV alloc] initWithNibName:#"MainView" bundle:nil]; //controller.delegate = self;
controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:controller animated:YES];
[controller release];
}
MainViewController.m
- (IBAction)startS {
SVController *controller = [[SVController alloc] initWithNibName:#"SView" bundle:nil]; controller.delegate = self;
controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:controller animated:YES];
[controller release];
}
Any suggestions?
If you want to call startS, which is a method on a MainViewController object, you can't call it on an EVController object.
[TheEVController startS];
tells the Objective-C runtime that you want to invoke the startS method in the TheEVController's class (or one of its parent classes).
It's not entirely clear from the code you posted (you didn't actually show us the section of code that is causing the exception) but from your description it sounds like you're overwriting a UIView variable that initially points to your MainViewController with a pointer to an EVController, and not resetting that variable when you show your MainViewController again.