Question

我有一个多视图的应用程序。在视图上我创建了NSDate如下：

NSString *storeDate = [[NSDate date] description];

在视图2上，viewDidLoad:我想使用

将标签的值（创建和链接的插座等）设置为storeDate值

timeRecord.text = storeDate;

我已导入我的观点，但storeDate被标记为未声明。

知道如何才能让它发挥作用吗？

SOFViewController.h

#import <UIKit/UIKit.h>

@interface SOFViewController : UIViewController {

}
-(IBAction) storeDateBut: (id) sender;
-(IBAction) goToView2: (id) sender;
@property (nonatomic,retain) NSString *storeDate;

@end

SOFViewController.m

#import "SOFViewController.h"
#import "view2.h"

@implementation SOFViewController
@synthesize storeDate;

-(IBAction) storeDateBut: (id) sender{

    self.storeDate = [[NSDate date] description];

}

-(IBAction) goToView2: (id) sender{
    view2 *myview2 = [[view2 alloc] initWithNibName:@"view2" bundle:nil];
    [self.view addSubview:myview2.view];

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

}

- (void)viewDidUnload {

}

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

@end

view2.h

#import <UIKit/UIKit.h>


@interface view2 : UIViewController {
    IBOutlet UILabel *dateLabel;

}

-(IBAction) goToView1: (id) sender;
@property (nonatomic, retain) IBOutlet UILabel *dateLabel;

@end

view2.m

#import "view2.h"
#import "SOFViewController.h"


@implementation view2
@synthesize dateLabel;

-(IBAction) goToView1: (id) sender{

    SOFViewController *mySOFViewController = [[SOFViewController alloc] initWithNibName:@"view2" bundle:nil];
    [self.view addSubview:mySOFViewController.view];



}

- (void)viewDidLoad {

    dateLabel.text = SOFViewController.storeDate;
    [super viewDidLoad];
}




- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    }

    - (void)viewDidUnload {
        [super viewDidUnload];

    }


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


    @end

Answer 1

storeDate的范围仅限于view1的方法。因此，您无法访问其他视图甚至同一类的其他方法。你必须制作“storeDate”属性，然后你可以在任何地方访问它，如

@interface view1:UIView {} 
@property(nonatomic, retain) NSString *storeDate;
@end

在实施中使用

@synthesize storeDate;

现在将storeDate的值设置为

self.storeDate = [[NSDate date] description];

你可以在任何地方使用它。

Answer 2

我从您的问题中假设您的意思是您的应用中有多个视图控制器。

storeDate只是您声明的方法的本地化。我认为您需要阅读variable scope in Objective-c

Answer 3

使用此代码。

在视图2中。

#import "view2.h"
#import "SOFViewController.h"

@implementation view2
@synthesize dateLabel;

-(IBAction) goToView1: (id) sender{

  SOFViewController *mySOFViewController = [[SOFViewController alloc]                 initWithNibName:@"view2" bundle:nil];
  [self.view addSubview:mySOFViewController.view];
}

- (void)viewDidLoad {

   dateLabel.text = mySOFViewController.storeDate;
   [super viewDidLoad];
}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];
}

- (void)viewDidUnload {
    [super viewDidUnload];

}


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

@end

将另一个视图上的标签设置为存储的NSDate

3 个答案: