The issue that I'm having is that I have My start page, then the user can select a button from there to open a settings page (Modal View). From the settings page the user selects the switch to turn on the PIN code page (another Modal View). I have been killing myself trying to implement this simple process. The app has a Nav&Tab Bar framework. I seem to can not get this right. The code Im using is as follows:
#import "SwitchResponderViewController.h"
#implementation SwitchResponderViewController
- (void)viewDidLoad {
[super viewDidLoad];
[sw addTarget:self action:#selector(switched) forControlEvents:UIControlEventValueChanged];
}
- (void)dealloc {
[secondController release], secondController = nil;
[super dealloc];
}
- (void)switched;
{
if ([sw isOn])
{
NSLog(#"On");
if (!secondController)
secondController = [[SecondViewController alloc] init];
[self presentModalViewController:secondController animated:YES];
}
else
{
NSLog(#"Off");
}
}
#end
I then create an IBOutlet UISwitch called sw in my view controller and hook it up in IB. However I cant get it to compile and work. Any ideas?
Let me get this straight. You're using a UISwitch to go to a new view when it's toggled? Maybe that's not what's going on, but it looks like it to me, and that's a bad way to do things.
Also, you've got an extra semicolon after -(void)switched
Related
i'm trying to build a quiz that sets the value of a UILabel dynamically through code.
i've done this successfully before, but for some reason it's not working this time. i suspect it's because the structure of this app is different. i've tried different fixes but haven't been able to get it to work.
the way my app is set up, i have a view controller with a view that has a segmented control. when you press one of the switches on the segmented control, it inserts a subview like this:
menuTable.hidden = YES;
additionPracticeController *additionPractice = [[additionPracticeController alloc]
initWithNibName:#"additionPractice"
bundle:nil];
self.addPracticeController = additionPractice;
[self.view insertSubview:additionPractice.view atIndex:0];
[additionPractice release];
the view controller for that subview displays its view like this:
- (void)viewWillAppear:(BOOL)animated{
firstNumberString = [NSString stringWithFormat:#"%d",arc4random() % 10];
firstNumberLabel.text = firstNumberString;
secondNumberLabel.text = secondNumberString;
[super viewWillAppear:animated]}
my outlets are connected and i can get the values to appear by setting them statically from the nib (even though that's not what i want). i've tried to set firstNumberString equal to all sorts of values, but nothing shows up when i set the values through code.
i'd really appreciate it if someone could help me solve this problem.
It sounds like you have the label connected in Interface Builder. I would need to see more code to know exactly what you are doing wrong. Make sure you are using a property for your label. The below code is a simple example of how this works.
ViewController.h
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController
{
IBOutlet UILabel *_displayMessage;
}
#property (nonatomic, retain) UILabel *displayMessage;
#end
ViewController.m
#import "ViewController.h"
#implementation ViewController
#synthesize displayMessage = _displayMessage;
- (void)viewDidLoad
{
[super viewDidLoad];
self.displayMessage.text = #"Text Changed!";
}
- (void)viewDidUnload
{
self.displayMessage = nil;
[super viewDidUnload];
}
- (void)dealloc
{
[_displayMessage release];
[super dealloc];
}
#end
Instead of making your class a subclass of UIControl just implement this method below. When the user hits done or return the keypad will resign
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
return YES;
}
To make the text field dismiss when the user taps outside of the text field.
Place this in ViewDidLoad:
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(dismissKeyboard)];
[self.view addGestureRecognizer:tap];
Place this method within the class:
-(void)dismissKeyboard
{
[aTextField resignFirstResponder];
}
Also if you want to dismiss the text field from another button spefically and not just a screen tap. Then just call this from within the button.
[your_textfield_name resignFirstResponder];
I've been trying to learn the new Storyboard feature in Xcode and I've run into a problem with trying to set a UITableView to edit mode.
So far my storyboard looks like this:
NavigationController -> UIViewController (subclass with tableview property)
I added a Navigation Item and a Bar Button item to the view controller scene, so I do see an edit button. It didn't do anything automagically, so I tried linking it's selector to the setEditing method of the tableview delegate. This did put it into editing mode. However, the edit button did not change to a "Done" button and so there is no way to get out of editing mode.
Do I have to create another Navigation item for the Done button? How do I connect it so that it appears at the right time and works correctly?
I think that also with Storyboard, the only way (for sure, the easiest one) to implement a working edit/done button, is to use the following code:
- (void)viewDidLoad
{
[super viewDidLoad];
...
//set the edit button
self.navigationItem.leftBarButtonItem = self.editButtonItem;
...
This is the solution that Apple itself implements if you select a "Master-Detail Application" template for your project.
Probably Storyboard is still not perfect, and hopefully it will be improved from Apple in next releases...
I just started using Storyboards, so I also wanted to use the Storyboard to add my Edit button. It is annoying to have taken the time to learn how to use a new tool but find you need a roll of duct tape to patch up the holes.
You can get it to work, but need to add a Custom button. In the Attributes inspector make sure the Identifier is Custom and the title is Edit.
Then add something like this in your .m
- (IBAction)setEditMode:(UIBarButtonItem *)sender {
if (self.editing) {
sender.title = #"Edit";
[super setEditing:NO animated:YES];
} else {
sender.title = #"Done";
[super setEditing:YES animated:YES];
}
}
Have your Custom Edit button call the setEditMode method.
Can only hope they will fix the implementation of the Edit button in the Storyboard editor in the future.
To summarize:
The Button, returned by UIViewController.editButtonItem is a special toggling button with special behavior that calls - (void)setEditing:(BOOL)editing animated:(BOOL)animated if pressed.
The Button, returned by UINavigationController.editButtonItem is a simple Button, just labeled with "Edit".
The Storyboard allows to select the latter one.
If you are using the navigation controller to push to the view controller, simply set self.navigationItem.rightBarButtonItem = self.editButtonItem;, which will put the default Edit button in the right. If the navigation bar is not visible, call self.navigationController.navigationBarHidden = NO;. Those would be called in the viewDidLoad method, or something similar. Then in order to get the tableView to respond to the edit call, use the following method:
- (void)setEditing:(BOOL)editing animated:(BOOL)animated {
[super setEditing:editing animated:animated];
[tableView setEditing:editing animated:animated];
}
That should do what you want it to do. If you have any issues, just say so and we can narrow down the details
To add to #Graham answer, you might also want to change the style so you can have the "Done" button style (the blue color). Something like this:
- (IBAction)setEditMode:(UIBarButtonItem *)sender {
if (self.editing) {
sender.title = #"Edit";
sender.style = UIBarButtonItemStylePlain;
[super setEditing:NO animated:YES];
} else {
sender.title = #"Done";
sender.style = UIBarButtonItemStyleDone;
[super setEditing:YES animated:YES];
}
}
one can use the dumb, not working Edit button from the Storyboard editor and then programmatically replace it with the UIViewController.editButtonItem.
in viewDidLoad:
NSMutableArray *toolbarItems = [NSMutableArray arrayWithArray:self.toolbarItems];
[toolbarItems replaceObjectAtIndex:0 withObject:self.editButtonItem];
[self setToolbarItems:toolbarItems];
this code assumes one has added the dumb Edit button as the leftmost item on the toolbar in the Storyboard.
In case that you have UIViewController and inside this you added a UITableVIew.
If you want to add an edit UIBarButton in order to interact with UITableView, try:
Add this line...
- (void)viewDidLoad
{
[super viewDidLoad];
...
self.navigationItem.leftBarButtonItem = self.editButtonItem;
...
}
and this method
- (void)setEditing:(BOOL)editing animated:(BOOL)animated {
[super setEditing:editing animated:animated];
[self.myListTableView setEditing:editing animated:animated];
if(self.myListTableView.editing) {
NSLog(#"editMode on");
} else {
NSLog(#"editMode off");
}
}
where
#property (weak, nonatomic) IBOutlet UITableView *myListTableView;
In the app im creating there are many pages that look mostly the same with some part which is different. To handle this kind of situation i created a container controller that contains a subview. I want this subview to be filled by the contents of another controller (and its associated nib) which i will created dynamically as needed based on context.
I have the following method somewhere
- (void) someAction {
UIViewController* contentController = [[MyContentController alloc] init];
UIViewController* containerController = [[MyContainerController alloc] initWithContentController:contentController];
[navigationController pushViewController:pageController animated:YES];
[contentController release];
[containerController release];
}
In MyContainerController.m i retain the controller in a property
- (id)initWithContentController:(UIViewController *)aContentController {
if ((self = [super initWithNibName:#"MyContainerController" bundle:nil])) {
contentController = aContentController;
}
return self;
}
Later in viewDidLoad i do the following
- (void)viewDidLoad {
[super viewDidLoad];
[contentViewContainer addSubview:contentController.view];
}
contentViewContainer is the view that's supposed to hold the page specific info.
Unfortunatly this fails with EXC_BAD_ACCESS.
The funny thing is that if i alloc and init the content controller from within viewDidLoad everything works. It seems that i cant pass a contoller i allocated from another place.
Can anyone assist.
Since you are releasing contentController in the actionMethod
you have to retain contentController in you init method
- (id)initWithContentController:(UIViewController *)aContentController {
if ((self = [super initWithNibName:#"MyContainerController" bundle:nil])) {
contentController = [aContentController retain];
}
return self;
}
But, why do you need this? Controllers are supposed to control views and no other controllers. If you think you really need that then you want to use UINavigationController or UITabBarController maybe.
You can also load views without a controller (see here)
I personally think that having UIViewControllers inside of simple UIViewController is not a preferable approach
Hope it helps
I need help figuring out how to change out the view in my application. I have a wonderfully working view that I have finished and now I'd like to be able to switch the view to a brand new, blank white screen to display.
I have these files:
HelloAppDelegate.h,
HelloAppDelegate.m,
HelloViewController.h, and
HelloViewController.m
Then, I added a new View Controller so now I have two more files:
SecondViewController.h and
SecondViewController.m
In my first view (HelloViewController), I have a button. When the user presses this button, I'd like SecondViewController to show up. So, in my HelloViewController.m, I have an action method
-(IBAction)switchToSecondView:(id)sender {
}
In this method, how can I go about initializing my second view and displaying it?
Thanks in advance!
If you want to do something like flipping view, making it modal and then returning back to the main view do following:
Define a delegate to indicate that secondary view finished its work
#protocol FlipsideViewControllerDelegate
- (void)flipsideViewControllerDidFinish;
#end
In main view do following:
- (void)flipsideViewControllerDidFinish {
[self dismissModalViewControllerAnimated:YES];
}
- (IBAction)showInfo {
FlipsideViewController *controller = [[FlipsideViewController alloc] initWithNibName:#"FlipsideView" bundle:nil];
controller.delegate = self;
controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:controller animated:YES];
[controller release];
}
In secondary view do following:
- (IBAction)done {
[self.delegate flipsideViewControllerDidFinish];
}
I am trying to release the label text each time the person click on a book title from the table view, it should change the detailViewController label (titleLabel) however it keeps showing the same book title.
Wondering If i have done something wrong - well I know I have but wondering how I fix it...
//
// BookDetailViewController.m
#import "BookDetailViewController.h"
#import "Book.h"
#implementation BookDetailViewController
#synthesize aBook, titleLabel;
// Implement viewDidLoad to do additional setup after loading the view.
- (void)viewDidLoad {
[super viewDidLoad];
[self bookDes];
self.title = #"Book Detail";
}
-(void)bookDes {
[self.titleLabel setText:nil];
[self.titleLabel setText:aBook.title];
}
- (void)dealloc {
[aBook release];
[titleLabel release];
[super dealloc];
}
#end
You are calling [self bookDes] from viewDidLoad... This method is called after a view controller has loaded its associated views into memory. How are you creating the BookDetailViewController? If you only create it once and then reuse the controller each time a user presses a book title, the viewDidLoad method will also only be called once.
If you already have the book title in your parent controller, why don't you just set the property from there when you push the child onto the navigation controller?
bookDetailsController.titleLabel.text = selectedBook.title;
EDIT FROM COMMENT:
Yes, the BookDetailsViewController is created once, then saved... so the viewDidLoad is only called once.
One thing you could try is setting the label in the parent's didSelectRowAtIndexPath method:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// Navigation logic -- create and push a new view controller
if(bdvController == nil)
bdvController = [[BookDetailViewController alloc] initWithNibName:#"BookDetailView" bundle:[NSBundle mainBundle]];
Book *aBook = [appDelegate.books objectAtIndex:indexPath.row];
bdvController.aBook = aBook;
bdvController.titleLabel.text = aBook.title;
[self.navigationController pushViewController:bdvController animated:YES];
}
there are better ways to do this like overriding the setter on the details controller and setting the label... but you should keep it simple and get it working first.
Hope this helps