1

经过几次尝试，我无法理解错误是错误以及为什么图像没有出现......这是我的代码。

我的协议.h

#import <Foundation/Foundation.h>

@protocol myProtocol <NSObject>

-(UIImage *)transferImage;

@end

视图控制器.h

#import "SecondViewController.h"

@interface ViewController : UIViewController<myProtocol, UINavigationControllerDelegate>
{
    UIView *view;
} 

@property (nonatomic,retain) UIImageView *imageView;

- (IBAction)sendImage:(id)sender; 

@end

视图控制器.m

#import "ViewController.h" 
#import "SecondViewController.h" 
#import "myProtocol.h"

@interface ViewController () 
@end 

@implementation ViewController

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    _imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"VoodooVibeThumb@2x.png"]];
    [view addSubview:_imageView];
    NSLog(@"VoodooVibeThumb@2x.png");
}

-(UIImage *)transferImage
{
    NSLog(@"VoodooVibeThumb@2x.png"); 
    return _imageView.image;
} 

- (IBAction)sendImage:(id)sender 
{    
    SecondViewController *secClass = [[SecondViewController alloc] init];
    [secClass setImageName:@"VoodooVibeThumb@2x.png"];
    [self.navigationController pushViewController:secClass animated:YES];
}

- (void)didReceiveMemoryWarning 
{
    [super didReceiveMemoryWarning];
} 

@end

SecondViewController.h

#import <UIKit/UIKit.h> 
#import "myProtocol.h" 
#import "ViewController.h"

@interface SecondViewController: UIViewController <myProtocol, UINavigationControllerDelegate>
{
    UIView *secondView;
    IBOutlet UIImageView *myImage;
    id <myProtocol> myDelegate;
}

@property (nonatomic,retain) UIImageView *myImage;
@property (nonatomic,retain) UIImage *transferImage;
@property(nonatomic,assign) id delegate;
@property (strong, nonatomic)NSString *imageName;

-(void)callTransfer;

@end

第二视图控制器.m

#import "SecondViewController.h"
#import "ViewController.h"
#import "myProtocol.h" 

@interface SecondViewController ()
@end 

@implementation SecondViewController

@synthesize delegate, myImage, transferImage;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
    // Custom initialization
}
return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
}

- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[myImage setImage:[UIImage imageNamed:_imageName]];
UIImageView * myImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:_imageName]];
[secondView addSubview:myImage];
}

-(void)callTransfer
{
    myImage.image=[delegate performSelector:@selector(transferImage)];
    myImage.image=[UIImage imageNamed:@"VoodooVibeThumb@2x.png"];
    NSLog(@"%@",myImage.image);
    NSLog(@"I am in call transfer");
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

@end
4

3 回答 3

1

用这个：

-(void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    myImage = [[UIImageView alloc] initWithImage[UIImage imageNamed:_imageName]];
    [secondView addSubview:myImage];
}

我假设您的界面（在 .h 或 .m 中）中有一个名为 myImage 的变量，因此当您创建 myImage 的本地实例（UIImageView *myImage）时，XCode 会感到困惑。由于它是最新声明的（没有引用，抱歉），它使用本地声明，但它知道有一个无法访问的使用相同名称的实例变量。UIImageView *相反，您希望通过从方法中删除直接保存到实例变量

希望这是有道理的！

马特

于 2013-10-18T15:42:22.863 回答
1

在将 myImage 子视图添加到 SecondViewController 的 viewDidLoad 方法之前，您似乎没有对其进行初始化。

尝试删除：

[secondView addSubview:myImage];

从 viewDidLoad 中，并将以下内容添加到 viewWillAppear：

UIImageView * myImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:_imageName]];

就在之前：

[secondView addSubview:myImage];

可能有更好的方法来做到这一点，但这可能会让你朝着正确的方向前进。

于 2013-10-15T23:48:52.097 回答
0

[secondView addSubview:myImage];

错误：“myImage”隐藏电阻变量的本地声明。

在此处输入图像描述

于 2013-10-18T15:31:58.690 回答