使用推视控制器时如何将Uiimage从一个视图控制器传递到其他视图控制器？

Question

I Have three View controllers.

First UIViewController contain one UIImage , when I click "crop" button, go to second view controller I pass the image by push view controller, here I'am cropping my UIImage . In second UIViewController which is inherited from image editor Viewcontroller after cropping my image, clicking "done" button.

I need to pass the cropped image to another view controller where i am having share button to share the post.

Problem is when I am puishing the editted image to another view controller in which share button is present,image is not passing.

Answer 1

You are saving the image in the Detail Controller before you make the push?

DetailController *detailVC=[[DetailController alloc]
                          initWithNibName:@"DetailController"
                          bundle:nil];

detailVC.image = self.image;

[self.navigationController pushViewController:detailVC animated:YES];

Answer 2

Delegation

You implement the protocol on your View Controller

In Controller.h :

@class Controller;

@protocol ControllerDelegate <NSObject>

- (void)sendFrom:(Controller *)controller
                   image:(UIImage *)image;

@end

@interface Controller : UIViewController

@property (weak, nonatomic) NSObject <ControllerDelegate> * delegate;

@end

In Controller.m when you want send the image:

[self.delegate sendFrom:self
         image: self.image];

After on your Detail View Controller , don't forget to assign it as delegate of the Controller . And to implement the ControllerDelegate protocol. To do that:

In your DetailController.h implement the protocol. You can do that on your .m as well.

#import "Controller.h"

@interface DetailController : UIViewController <ControllerDelegate>

You keep a reference of the Controller in The Detail Controller

@property (nonatomic, strong) ViewController *controller;

And assign its delegate in the viewDidLoad of the Detail Controller . For example:

-(void)viewDidLoad:(BOOL)animated{

      [super viewDidLoad:animated];

      self.controller.delegate = self;
   }

Don't forget to implement the protocol method in your Detail View. Here you receive the image you passed from Controller and you save it in your Detail Controller UIImage property:

- (void)sendFrom:(Controller *)controller
                       image:(UIImage *)image{

   self.image = image;
}

Answer 3

You can implement storyboard segue to your detail controller and use following sample code.

- (void)cropButtonClick:(id)sender
{
    [self performSegueWithIdentifier: @"MySegue" sender:sender];
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.identifier isEqualToString:@"MySegue"]) {
        DetailController *detailVC = segue.destinationViewController;
        [detailVC setImage:self.image];
    }
}