This seems to be quite trivial but somehow I can't get it to work. I have 2 Popover Controllers with a tableView as contents, and I have a UIViewController with some buttons.
I'm setting one of the button's title from the PopoverController's didSelectRoxAtIndexPath function. This works nicely. Now I would like to pass this button title to the second PopoverController but can't seem to get this to work; the string returns a NULL. Currently I'm using:
h file:
NSString *myString;
#property(nonatomic,retain)NSString *myString;
m file:
#synthesize myString;
in viewDidLoad:
MyAppViewController *appV = [[MyAppViewController alloc]initWithNibName:#"MyAppViewController" bundle:nil];
self.myString = appV.buttonOne.currenTitle;
Try setting setting this property before displaying the second UIPopoverController.
Related
how I can get the value of my UITextField ? When I declare my UITextField in the Storyboard, I know but like this, I don't know.
(sorry for my English, I'm French)
Thank you in advance for your answer.
//Ajout d'un Text Field
CGRect rectTF = CGRectMake(10,70,100,20); // Définition d'un rectangle
UITextField *articleSaisi = [[UITextField alloc] initWithFrame:rectTF];
articleSaisi.borderStyle = UITextBorderStyleLine;
articleSaisi.placeholder = #"Article";
[self.view addSubview: articleSaisi];
I am not quite sure whether you want to access the value or you want to associate your UI element to your code:
Try this if you are saying that you want to access the text value.
atricleSaisi.text
Try to control drag the UI element to either your corresponding .h or .m file so that it can create IBOutlet for you if you are saying that you want to connect your UI element to your code.
Highly recommend you go check the documentation.
if you want to know when the user pressed return, as per your comment, then you should create a UITextViewDelegate for your text view and define its textFieldShouldReturn method:
Discussion
The text field calls this method whenever the user taps the return button. You can use this method to implement any custom behavior when the button is tapped.
Also, give a look at textFieldDidEndEditing, which is called whenever there is a focus change and you should define to correctly handle user input.
Old answer:
If I do not understand you incorrectly, you want to create a UITextField programmatically (i.e., not through a Storyboard).
In this case, you should put you initialisation code inside the viewDidLoad method of your view controller and make sure that you define a property for the text field instead of a local variable:
#interface MyViewController : UIViewController
....
#property (nonatomic, strong) UITextField* articleSaisi;
...
#end
- (void)viewDidLoad {
CGRect rectTF = CGRectMake(10,70,100,20); // Définition d'un rectangle
self.articleSaisi = [[UITextField alloc] initWithFrame:rectTF];
self.articleSaisi.borderStyle = UITextBorderStyleLine;
self.articleSaisi.placeholder = #"Article";
[self.view addSubview:self.articleSaisi];
}
If you do so, you can access the text field value from any other method in the view controller through its text property:
self.articleSaisi.text
I have a table controller in which I use didSelectRowAtIndexPath to navigate from the pushed cell to another view. In it I initialize new view controller and push some data in it. After that I do pushViewController.
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
// Navigation logic may go here. Create and push another view controller.
ServicesModel *service = [services objectAtIndex:indexPath.row];
ServiceViewController *serviceViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"ServiceView"];
serviceViewController.serviceModel = service;
NSLog(#"Set model %#", service.title);
// Pass the selected object to the new view controller.
[self.serviceController pushViewController:serviceViewController animated:YES];
}
In my ServiceViewController I have a label serviceTitle and ServiceModel property for selected service
#property (weak, nonatomic) IBOutlet UILabel *serviceTitle;
#property (strong, nonatomic) ServiceModel *serviceModel;
Using viewDidLoad I'm trying to change text of the label
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
NSLog(#"viewDidLoad %#", self.serviceModel.title);
self.serviceTitle.text = self.serviceModel.title;
}
Also I'm trying to access model in viewDidAppear
- (void) viewDidAppear:(BOOL)animated
{
NSLog(#"viewDidAppear %#", self.serviceModel.title);
}
but when view opens, label is empty. Why? What am I doing wrong? The most strange is the log:
(-[ServiceViewController viewDidLoad]) (ServiceViewController.m:43) viewDidLoad (null)
(-[ServicesTableViewController tableView:didSelectRowAtIndexPath:]) (ServicesTableViewController.m:127) Set model Google.com
(-[ServiceViewController viewDidAppear:]) (ServiceViewController.m:36) viewDidAppear (null)
It shows that viewDidLoad fires before I assign the model property. And in viewDidAppear model property is still null. How it can be?
You have two problems. The first one, as 0x7fffffff mentioned, is that you're instantiating your controller incorrectly (it should be initWithNibName:bundle: if made in a xib, and like 0x7fffffff said if in a storyboard).
Second, you can't access the label in serviceViewController from didSelectRowAtIndexPath, because its view has not been loaded yet. So, instead of setting the label in didSelectRowAtIndexPath, you should have a string property in serviceViewController, and give it the value service.text. Then in viewDidLoad, you can populate your label with that string.
Is the label missing altogether, or do you see it and it just didn't receive updated text? If the label is missing, then it's probably a problem in how you're creating the view controller. If for example, you're using storyboards, you should be accessing the view controller like this:
ServiceViewController *controller = [self.storyboard instantiateViewControllerWithIdentifier:#"SomeStoryBoardID"];
Instead of this:
ServiceViewController *serviceViewController = [[ServiceViewController alloc] init];
If however, you can see the label, but it just hasn't updated it's text, the first thing you should to is examine the connections inspector in Interface Builder, and verify that the IBOutlet for the label is properly linked.
I was wondering how I could access data from another class using Xcode 4.2 and Storyboard?
Say for instance how would I access the text of a text field from another class?
Google hasn't helped and the lesson on MyCodeTeacher.com about this is outdated and doesn't work anymore...
Thanks for bearing with me!
-Shredder2794
Not sure if this is the only or best way, but you can create a property in the destination view's .h file and set it to a value before the segue is performed
in the destination view controller's .h file:
#interface YourDestinationViewController : UIViewController
{
NSString* _stringToDisplay;
//...
}
#property (nonatomic, retain) NSString* stringToDisplay;
//...
and in the presenting view's .m file
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
YourDestinationViewController*viewController = segue.destinationViewController;
viewController.delegate = self;
viewController.stringToDisplay = #"this is the string";
}
Then you can do what you want with the property in whichever of the viewWillAppear/viewDidLoad/viewDidAppear/etc. methods best suits your purpose in the destination view's .m file
And then to check if it works, in the destination view controller's .m file:
-(void)viewWillAppear:(BOOL)animated
{
NSLog(#"self.stringToDisplay = %#", self.stringToDisplay);
...
//and if a label was defined as a property already you could set the
//label.text value here
}
Edit: Added more code, and made it less generic
This isn't specific to Storyboard. There are several ways to do what you are trying to do. You could declare a variable in your AppDelegate (an NSString) and set that in your first class. Then in your second class access the AppDelegate variable and use that to set your label. The code to do this is:
AppDelegate *appDelegate = (AppDelegate*)[[UIApplication sharedApplication] delegate];
label.text = appDelegate.myString;
Another way to do it (probably the easiest) is to declare an NSString in your second class. Then in your first class, before you push the second view set that string variable. Something like this:
MyViewController *vc = [[MyViewController alloc] initWithNibName:#"" bundle:nil];
vc.myString = #"";
The third way to do this is using delegates. This is the most 'complicated' way but is the best. You would create a delegate which gets called when your second view appears. The delegate could then return the value from the first class to you.
You may also be able to use the new completion handler block on the iOS 5 pushViewController: method.
Edit:
Custom init method:
- (void)initWithNibName:(NSString *)nibName bundle:(NSString *)bundle string:(NSString *)myString
And then when you are pushing the view just class this method and set the string through it.
So I'm attempting to deal with uitabbarcontroller and wanted to have a default tab be selected when the view loads.
I have tried setting the
#property (nonatomic) int selectedIndex;
however this just sets which viewcontroller is being shown, not the actual tabbar being selected
I also tried this line
[self tabBar].selectedItem = [[[self tabBar] items] objectAtIndex:0];
but it crashes as you are not allowed to mutate the tabbar of a tabbarcontroller
Any help with this?
Thanks
So, as discussed in the comments, following code should do what you want:
[self.tabBarController setSelectedIndex:desiredIndex];
Alternatively, you can use:
[self.tabBarController setSelectedViewController:desiredViewController];
I have trouble changing the text in a label programmatically.
When I run the following code, NSLog does display "Setting myLabel to = Hello World!", but the label on the screen is not changed.
UIViewOverlay *overlayWindow;
overlayWindow = [[[NSBundle mainBundle] loadNibNamed:#"UIViewOverlay" owner:self options:nil] objectAtIndex:0];
[self addSubview:overlayWindow];
[overlayWindow setMyLabel:#"Hello World!"];
My NIB file has a 300x300 window with some labels and buttons.
There is a label, which is connected to myLabel in the outlet. The UIView does display, just that the text cannot be changed programmatically.
UIViewOverlay.h
#import <UIKit/UIKit.h>
#interface UIViewOverlay : UIView {
IBOutlet UILabel *myLabel;
}
- (void)setMyLabel:(NSString *) label;
#end
UIViewOverlay.m
#import "UIViewOverlay.h"
#implementation UIViewOverlay
- (void)setMyLabel:(NSString *) label {
myLabel.text = label; // THIS LINE IS NOT WORKING! :-(
NSLog(#"Setting myLabel to = %#", label); // This line is working.
}
#end
Thanks in advance..
You are using an incorrect accessor name for your method to set the label string.
In cocoa, setFoo is the method by which an instance variable called foo is assigned. This isn't just a convention, many areas of functionality depend on it, for example the use of properties, key value coding etc.
In your code, your label is called myLabel. Your method to set the text of that label is called setMyLabel. Either this is causing your outlet to not be connected when the nib is loaded, as the runtime may be trying to use that method to assign the label to your instance variable in the first place, or all of the above has no effect and you have just not connected your outlet.
Make sure you have an object in your code for the label, like this example:
IBOutlet UILabel* aLabel;
And in interface builder (you may have already done this): Connect the aLabel (or whatever name you use) outlet to the actual label. This can be done by control clicking and dragging from the File’s Owner object, in the document window, to the label, in the view. A small, gray window will appear with at least two options, one will be the aLabel defined earlier, and the other will be the view (this is a default outlet required for viewcontrollers, it will have a dash to indicate it is already connected to something). Click on the aLabel option to select it. (I'll be honest, without my mac in front of me I copied most of this paragraph's instructions from this link.)
You have an object called aLabel that you can now treat like any other variable. If you want to change the text value, try this:
aLable.text = #"some text";
Maybe you did not make the connection. Can you try the following?
#import "UIViewOverlay.h"
#implementation UIViewOverlay
- (void)showMyLabel:(NSString *) label {
NSLog(#"My current label contents (myLabel) = %#", myLabel.text); // ** changed to myLabel.text
}
#end
If you aren't able to print the original value, then you aren't connected.
I hope that helps.