[英]Show image in SecondViewController when button is clicked in FirstViewController
[英]How to show image in SecondViewController when button is clicked in FirstViewController
经过几次尝试后,我未能成功理解是错误以及为什么没有出现图像...这是我的代码。
myProtocol.h
#import <Foundation/Foundation.h>
@protocol myProtocol <NSObject>
-(UIImage *)transferImage;
@end
ViewController.h
#import "SecondViewController.h"
@interface ViewController : UIViewController<myProtocol, UINavigationControllerDelegate>
{
UIView *view;
}
@property (nonatomic,retain) UIImageView *imageView;
- (IBAction)sendImage:(id)sender;
@end
ViewController.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
SecondViewController.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
看来您没有在将myImage子视图添加到SecondViewController的viewDidLoad方法之前对其进行初始化。
尝试删除:
[secondView addSubview:myImage];
从viewDidLoad中添加以下内容到viewWillAppear中:
UIImageView * myImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:_imageName]];
之前:
[secondView addSubview:myImage];
这样做可能会有更好的方法,但是这可能使您朝正确的方向前进。
用这个:
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
myImage = [[UIImageView alloc] initWithImage[UIImage imageNamed:_imageName]];
[secondView addSubview:myImage];
}
我假设您的界面中有一个名为myImage的变量(无论是.h还是.m),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(无引用,对不起),它使用的是本地声明,但是它知道存在一个使用相同名称的实例变量,该实例变量无法访问。 相反,您想通过从方法中删除UIImageView *
直接保存到实例变量
希望这有道理!
马特
[secondView addSubview:myImage];
错误:“ myImage”隐藏阻力变量的本地声明。
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