Question

我创建了两个视图，每个视图有四个文本字段。我有一个开关，允许我在这两个视图之间来回切换。当激活/取消激活开关时，它会将当前文本字段数据传递到目标ViewController，反之亦然。

以下代码最初工作正常。如果我在三个文本字段中输入数据，比如说，在FirstViewController中，我按下了开关，数据出现在SecondViewController的相应三个文本字段中。如果我再次按下开关，来自相同三个文本字段的数据将填充FirstViewController中的相应文本字段。

添加了一些与这些特定文本字段和切换无关的视图，标签，按钮等，现在代码不再有效，我无法弄清楚原因。只有最后输入的文本字段数据才会传递到目标，因此如果我在三个文本字段中输入数据，则只传递最后输入的数据。如果我再次切换开关，现在没有数据传递。

任何人都可以帮我指出正确的方向，为什么这段代码最初有效，但现在不行？谢谢。

FirstViewController.h

import <UIKit/UIKit.h>

@interface FirstViewController : UIViewController

//Defines input value for each of the four textfields
@property (weak, nonatomic) IBOutlet UITextField *textFieldA;
@property (weak, nonatomic) IBOutlet UITextField *textFieldB;
@property (weak, nonatomic) IBOutlet UITextField *textFieldC;
@property (weak, nonatomic) IBOutlet UITextField *textFieldD;

@property (weak, nonatomic) NSString *textFieldAContent;
@property (weak, nonatomic) NSString *textFieldBContent;
@property (weak, nonatomic) NSString *textFieldCContent;
@property (weak, nonatomic) NSString *textFieldDContent;

@end

FirstViewController.m

#import "FirstViewController.h"
#import "SecondViewController.h"

@interface FirstViewController ()
@end

@implementation FirstViewController

@synthesize textFieldA;
@synthesize textFieldB;
@synthesize textFieldC;
@synthesize textFieldD;
@synthesize textFieldAContent;
@synthesize textFieldBContent;
@synthesize textFieldCContent;
@synthesize textFieldDContent;

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.textFieldA.text = self.textFieldAContent;
    self.textFieldB.text = self.textFieldBContent;
    self.textFieldC.text = self.textFieldCContent;
    self.textFieldD.text = self.textFieldDContent;
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.identifier isEqualToString:@"FirstToSecondView"])
    {
        SecondViewController *controller = (SecondViewController *)segue.destinationViewController;
        controller.textFieldAContent = self.textFieldA.text;
        controller.textFieldBContent = self.textFieldB.text;
        controller.textFieldCContent = self.textFieldC.text;
        controller.textFieldDContent = self.textFieldD.text;
    }
}
@end

SecondViewController.h

import <UIKit/UIKit.h>

@interface SecondViewController : UIViewController

//Defines input value for each of the four textfields
@property (weak, nonatomic) IBOutlet UITextField *textFieldA;
@property (weak, nonatomic) IBOutlet UITextField *textFieldB;
@property (weak, nonatomic) IBOutlet UITextField *textFieldC;
@property (weak, nonatomic) IBOutlet UITextField *textFieldD;

@property (weak, nonatomic) NSString *textFieldAContent;
@property (weak, nonatomic) NSString *textFieldBContent;
@property (weak, nonatomic) NSString *textFieldCContent;
@property (weak, nonatomic) NSString *textFieldDContent;

@end

SecondViewController.m

#import "SecondViewController.h"
#import "FirstViewController.h"

@interface SecondViewController ()
@end

@implementation SecondViewController

@synthesize textFieldA;
@synthesize textFieldB;
@synthesize textFieldC;
@synthesize textFieldD;
@synthesize textFieldAContent;
@synthesize textFieldBContent;
@synthesize textFieldCContent;
@synthesize textFieldDContent;

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.textFieldA.text = self.textFieldAContent;
    self.textFieldB.text = self.textFieldBContent;
    self.textFieldC.text = self.textFieldCContent;
    self.textFieldD.text = self.textFieldDContent;
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.identifier isEqualToString:@"SecondToFirstView"])
    {
        FirstViewController *controller = (FirstViewController *)segue.destinationViewController;
        controller.textFieldAContent = self.textFieldA.text;
        controller.textFieldBContent = self.textFieldB.text;
        controller.textFieldCContent = self.textFieldC.text;
        controller.textFieldDContent = self.textFieldD.text;
    }
}
@end

Answer 1

跟进我的问题。我从来没有弄清楚问题是什么，但是当用户redelmar评论到原始帖子时，我不应该使用segue来回（每次我转换视图时内存使用率都会上升）。相反，我在一个ViewController上做了我打算做的所有事情。谢谢你的帮助！

在视图之间传递文本字段数据

1 个答案: