How to pass a value to anotherviewcontroller? - iphone

Question

Hello everybody, I have a UITableView in a UIViewController. When a row in the table is tapped I am collecting the cell's text value and putting it in a string called localstringGValue.
I want to pass this string and display it in another, viewController, but without using -pushViewController: I want this value to be stored somewhere like NSUserDefaults or NSDictonary and then, on viewWillapper of the other view controller I want this stored value to be displayed in a label.
in my .h:
NSString *localStringGValue;
in my .m:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:YES];
localStringGValue = [tableView cellForRowAtIndexPath:indexPath].textLabel.text;
}
in my other view controller:
-(void)viewWillAppear
{
label.text=localStringGValue;
}
Thanks in advance.

Answer 1

save to nsuserdefaults:
[[NSUserDefaults standardUserDefaults] setObject:localstringGValue forKey:#"localstringGValue"];
[[NSUserDefaults standardUserDefaults] synchronize];
retrieve from nsuserdefaults:
NString *localstringGValue = [[NSUserDefaults standardUserDefaults] objectForKey:#"localstringGValue"];

Answer 2

Just use delegate. Before you push the 'UploadViewController' instance, you need set it's delegate as self(in GoogleDocMainPageController.m). Everytime, the tabel cell is selected, it'll set value for self.delegate(Here is GoogleDocMainPageController instance) by dispatching self.delegate's method, which is implemented by GoogleDocMainPageController:
[self.delegate setDataAfterSelectedTabelCell:[NSString stringWithFormat:#"TalbeCell %d selected", [indexPath row]]];
The main code is shown below:
UploadViewController.h:
#import <UIKit/UIKit.h>
#class UploadViewController;
#protocol UploadViewControllerDelegate <NSObject>
- (void)setDataAfterSelectedTabelCell:(NSString *)stringValueInCell;
#end
#interface UploadViewController : UITableViewController
#property (nonatomic, retain) id <UploadViewControllerDelegate> delegate;
#end
UploadViewController.m:
//...
#synthesize delegate = _delegate;
//...
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[self.delegate setDataAfterSelectedTabelCell:[NSString stringWithFormat:#"TalbeCell %d selected", [indexPath row]]];
}
GoogleDocMainPageController.h:
#import <UIKit/UIKit.h>
#import "UploadViewController.h"
#class UploadViewController;
#interface GoogleDocMainPageController : UIViewController <UploadViewControllerDelegate>
- (void)loadUploadViewController;
#property (nonatomic, retain) UILabel * glLabel;
#property (nonatomic, retain) UploadViewController * uploadViewController;
#end
GoogleDocMainPageController.m:
//...
#synthesize glLabel = _glLabel;
#synthesize uploadViewController = _uploadViewController;
//...
- (void)viewDidLoad
{
[super viewDidLoad];
UIButton * uploadButton = [[UIButton alloc] initWithFrame:CGRectMake(10.0f, 160.0f, 300.0f, 35.0f)];
[uploadButton setBackgroundColor:[UIColor blackColor]];
[uploadButton setTitle:#"Upload Button" forState:UIControlStateNormal];
[uploadButton addTarget:self action:#selector(loadUploadViewController) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:uploadButton];
[uploadButton release];
self.glLabel = [[UILabel alloc] initWithFrame:CGRectMake(10.0f, 200.0f, 300.0f, 35.0f)];
[self.glLabel setBackgroundColor:[UIColor blackColor]];
[self.glLabel setTextColor:[UIColor whiteColor]];
[self.glLabel setTextAlignment:UITextAlignmentCenter];
[self.glLabel setText:#"Default"];
[self.view addSubview:self.glLabel];
self.uploadViewController = [[UploadViewController alloc] initWithStyle:UITableViewStylePlain];
}
//...
#pragma mark -
- (void)loadUploadViewController
{
[self.uploadViewController setDelegate:self];
[self.navigationController pushViewController:self.uploadViewController animated:YES];
}
#pragma mark - UploadViewControllerDelegate
- (void)setDataAfterSelectedTabelCell:(NSString *)stringValueInCell
{
[self.glLabel setText:stringValueInCell];
}

Answer 3

Why don't you declare some #property(nonatomic,retain) and #synthesize it ? Then the getters/setters will be automatically created. Otherwise, define some getter/setters yourself.

Answer 4

Go through Following Steps-
In First ViewController -
Create Object of second ViewController
like SecondViewController *sec= [[SecondViewController alloc]init];
sec.myLable=#"My Lable String";
In Second ViewController -
In .h file
UILable *myLable;
#property(nonautomic,retain)IBOutlet UILable *myLable;
2.In .m file
#synthesize myLable;