Change UIImage view between two View Controllers - iphone

Question

It's possible to change an image by clicking on a button inside an other View Controller?
I use this code in order to pass the data from the ViewController to the SecondViewController. I would want to add to the same button the commando to add an image to the SecondViewController... Excused my poor question...
ViewController.h
#import <UIKit/UIKit.h>
#import "SecondViewController.h"
#interface ViewController : UIViewController <SecondViewControllerDelegate> {
IBOutlet UITextField *userNameTextField;
}
#property (nonatomic, strong) UITextField *userNameTextField;
#end
ViewController.m
#import "ViewController.h"
#import "SecondViewController.h"
#interface ViewController ()
#end
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
if([segue.identifier isEqualToString:#"to2"]){
SecondViewController *viewController = segue.destinationViewController;
viewController.delegate = self;
}
}
- (void)done:(NSString *)name{
[self dismissViewControllerAnimated:YES completion:nil];
NSLog(#"Back in first ViewController, metod Done, with name=%#",name);
userNameTextField.text=name;
}
#end
SecondViewController.h
#import <UIKit/UIKit.h>
#protocol SecondViewControllerDelegate <NSObject>
-(void) done:(NSString*)someText;
#end
#interface SecondViewController : UIViewController {
IBOutlet UITextField *someText;
IBOutlet UIButton *returnButton;
id delegate;
}
#property (nonatomic, assign) id <SecondViewControllerDelegate> delegate;
#property (nonatomic, strong) UITextField *someText;
- (IBAction)returnButtonPressed:(id)sender;
#end
SecondViewController.m
#import "SecondViewController.h"
#interface SecondViewController ()
#end
#implementation SecondViewController
#synthesize someText;
#synthesize delegate = _delegate;
- (IBAction)returnButtonPressed:(id)sender {
[self.delegate done:someText.text];
}
#end

Answer 1

Here is one way that should work for you:
Just set up an NSNotification in your ViewController with the image. Trigger the notification in the other viewController when the button is pressed.
in your image's view controller:
//in ViewDidLoad:
[[NSNotificationCenter defaultCenter]addObserver:self selector:#selector(changeTheImage) name:#"CHANGE_THE_IMAGE" object:nil];
//then elsewhere in the class:
- (void)changeTheImage {
//change your image here
}
//and in your dealloc, make sure you add this, or it will keep "observing"
[[NSNotificationCenter defaultCenter] removeObserver:self];
Then in the button view controller:
//have this as your button action (or add the line to your button action)
- (IBAction)yourButtonWasPressed:(id)sender {
[[NSNotificationCenter defaultCenter]postNotificationName:#"CHANGE_THE_IMAGE" object:self];

Answer 2

What's the mean to change another UIViewController. because when you click on current UIViewController that's mean the current is on top and visible. what you called another can only be overlap inactive or it's does not exist right now.
So if you want somehow to change the UIImage from another UI, the simplest way is to hold the UIImage or image file name in a global store area such as your AppDelegate class, file. when click change the global area content. and in the ui for image show you can add some code in
- (void)viewWillAppear:(BOOL)animated {
//read and change UIImage content from global store
}
is it what you want ?