将信息从视图控制器发送到另一个

Posted 2023-03-21

【中文标题】将信息从视图控制器发送到另一个

【英文标题】：Sending information from a view controller to another

【发布时间】：2013-03-08 16:23:16

【问题描述】：

问题是，我在视图控制器 (ViewController) 上有 9 个按钮，并且我有一个插座集合用于存储所有这些按钮插座。

然后我有一个动作方法来处理这些按钮的点击事件。

我想要的是发送 CLICKED 按钮的按钮图像背景（作为 UIImage * img），segue 到另一个视图控制器（vc2），

这是我的代码：

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *cardBtns;


- (IBAction)cardAction:(id)sender;

@end




#import "ViewController.h"
#import "ResultViewController.h"

@interface ViewController ()
@property(strong,nonatomic)UIImage *image;
@end

@implementation ViewController

- (void)viewDidLoad

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


- (void)didReceiveMemoryWarning

[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.


- (IBAction)cardAction:(id)sender 
for(UIButton *cardButton in self.cardBtns)
    self.image = [cardButton currentBackgroundImage];

[self performSegueWithIdentifier:@"cardSegue" sender:self.image];


- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
//UIImage * img = [UIImage imageNamed:@"f1"];
UIImage * img = (UIImage *)sender;

ResultViewController *viewcontroller = [segue destinationViewController];
viewcontroller.img = img;


@end

在vc2中，我这里有另一个按钮，我希望用刚刚从vc1 segue发送的img来绘制这个按钮背景img。

@interface ResultViewController : UIViewController
@property (weak, nonatomic) IBOutlet UIButton *cardBtn;
@property(strong,nonatomic)UIImage *img;

- (IBAction)cardDismiss:(id)sender;

@end



#import "ResultViewController.h"

@interface ResultViewController ()

@end

@implementation ResultViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil

self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) 
    // Custom initialization

return self;


- (void)viewDidLoad

[super viewDidLoad];
[self.cardBtn setImage:self.img forState:UIControlStateNormal];


- (void)didReceiveMemoryWarning

[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.



- (IBAction)cardDismiss:(id)sender 
[self dismissViewControllerAnimated:NO completion:nil];

@end

假设我的按钮是 1,2,3,4,5,6,7,8,9

现在，无论我在 vc1 中单击什么按钮，它在 vc2 中始终显示为“6”... 有什么建议么？谢谢

【问题讨论】：

为什么for 循环会覆盖self.image？

【参考方案1】：

问题是这样的：

- (IBAction)cardAction:(id)sender 
for(UIButton *cardButton in self.cardBtns)
    self.image = [cardButton currentBackgroundImage];

[self performSegueWithIdentifier:@"cardSegue" sender:self.image];

这会将 self.image 设置为 self.cardBtns 中的最后一项。您想将 self.image 设置为 sender.currentBackgroundImage （并将参数类型中的 id 更改为 UIButton *），然后消除循环。