CODEWITHSUNDEEP
objective-ciosuiviewcontrolleruilabeluitextview
d.altman
d.altman

Reputation: 455

Stuck trying to get the NSString from a UILabel in one Viewcontroller to place in a UITextView of another Viewcontroller

I have an app with two viewcontrollers and I want to show the text from a UILabel in VC1 in a UITextView inside of VC2.

I have been able to access the UILabel from VC1 in the viewDidLoad of VC2 but the actual text does not appear.

In VC2 I created a VC1 object and can access VC1. Here is the VC2 viewDidLoad:

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.textView.text = vc1Controller.label.text;
}

But when I run the app and the VC2 appears, nothing appears in the UITextView. I do have it wired and can show text by doing an NSLog(@”Yes”); for example in the above method.

When I do an NSLog(@”%@”, vc1Controller.label.text); I get NULL in the output.

Do I need to create a custom getter? Any advice appreciated. I’m relatively new to all programming.

Upvotes: 0

Views: 154

Answers (3)

FreeAppl3
FreeAppl3

Reputation: 858

This is how you pass a NSString from views:

First View:

@interface ViewController : UIViewController{
IBOutlet UILabel *firstLbl;
NSString *firstString;
}

-(IBAction)labelTouched:(id)sender;

@end

@implementation ViewController

- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.

firstString = @"I'm the first labels text";
firstLbl.text = firstString;

}


-(IBAction)labelTouched:(id)sender{

ViewController2 *view2 = [[ViewController2 alloc] init];
view2.selectedFirstLabelString = firstString;
[self presentModalViewController:view2 animated:YES];
[view2 release];
}

SecondView:

@interface ViewController2 : UIViewController{
IBOutlet UILabel *secondLbl;
}
@property (nonatomic, retain)NSString *selectedFirstLabelString;

-(IBAction)done:(id)sender;
@end



@implementation ViewController2
@synthesize selectedFirstLabelString;


- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.

secondLbl.text = selectedFirstLabelString;
}

Hope this helps.

Upvotes: 1

Nitin Alabur
Nitin Alabur

Reputation: 5812

When you create a VC1 object in VC2, you are obviously not referring to the VC1 that pushed VC2.

Your vc2 is trying to read a label value from the newly created vc1, while you actually want to read the value from the VC1 that pushed VC2.

There are a few ways you can get your code working:

1) accessing the parentViewController (if you are presenting vc2 as modal)

In VC2, you can refer to your parent controller:

VC1* vc = (VC1 *)self.parentViewController; VC2.textView.text = vc.label.text;

2) Accessing the vc1 from the navigationcontroller stack: How to access the stack in UINavigationController This post has it all

3) Use Delegate pattern. Custom delegate This one has it all!

Hope you find this useful.

Upvotes: 1

djweber
djweber

Reputation: 106

In the line:

self.textView.text = [vc1Controller self.label.text];

You are using the self keyword in [vc1Controller self.label.text], but that is going to reference a nonexistent UILabel in the current view controller (View Controller 2). Make the label in vc1Controller a property, and then use:

vc1Controller.label.text;

to access its text value.

Upvotes: 1

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