使用代理更改标签文本颜色

Z时代
2024-01-10
分类：问答

我有两个视图控制器，ParentViewController的标签使用SecondViewController更新。现在我想更改ParentViewController的标签文本颜色从ChildViewController，因为我使用协议和委托，但它显示错误。使用代理更改标签文本颜色

我的代码是这样的：

ChildViewController.h

@protocol ViewControllerDelegate 
-(void) updateLabel; 
@end 
@interface ChildViewController : UIViewController<UITextFieldDelegate,UITextViewDelegate> 
{ 
    id <ViewControllerDelegate> delegate; 
} 
@property (assign) id <ViewControllerDelegate> delegate; 
@end

ChildViewController.m

@implementation childViewController 
@synthesize delegate; 
- (IBAction)backBtn:(id)sender { 
    [delegate updateLabel]; 
} 
@end

ParentViewController.h

#import <UIKit/UIKit.h> 
#import "childViewController.h" 
@interface ParentViewController : UIViewController<UserResizableViewDelegate,ViewControllerDelegate> 
@end

ParentViewController.m

@implementation ParentViewController 
- (void)viewDidLoad 
{ 
    ChildViewController.delegate=self; //here it show error that ChildViewController does not have property delegate 
} 
- (void)updateLabel 
{ 
    alabel.textColor = [UIColor blueColor]; 
} 
@end

UPDATE

我这是怎么创建标签

ParentViewController.m

- (void)viewDidLoad 
{ 
CGRect imageFrame = CGRectMake(10, 10, 150, 80); 
    labelResizableView = [[UserResizableView alloc] initWithFrame:imageFrame]; 
    alabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 100, 100)]; 
    alabel.text = @"Drag me!"; 
    //alabel.text = self.newsAsset.title; 
    alabel.adjustsFontSizeToFitWidth = NO; 
    alabel.autoresizingMask = UIViewAutoresizingFlexibleWidth; 
    alabel.font = [UIFont boldSystemFontOfSize:18.0]; 
    //alabel.textColor = [UIColor blueColor];  
    // alabel.shadowColor = [UIColor whiteColor]; 
    // alabel.shadowOffset = CGSizeMake(0, 1); 
    alabel.backgroundColor = [UIColor clearColor]; 
    alabel.lineBreakMode = UILineBreakModeWordWrap; 
    alabel.numberOfLines = 10; 
    alabel.minimumFontSize = 8.; 
    alabel.adjustsFontSizeToFitWidth = YES; 
    [alabel sizeToFit]; 
    labelResizableView.autoresizingMask = UIViewAutoresizingFlexibleWidth; 
    // enable touch delivery 
    alabel.userInteractionEnabled = YES; 
    UITapGestureRecognizer *doubleTap =[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(labelTap:)]; 
    doubleTap.numberOfTapsRequired = 2; 
    [self.view addGestureRecognizer:doubleTap]; 
    //Calculate the expected size based on the font and linebreak mode of your label 
    CGSize maximumLabelSize = CGSizeMake(296,9999); 
    CGSize expectedLabelSize = [myString sizeWithFont:alabel.font 
            constrainedToSize:maximumLabelSize 
             lineBreakMode:alabel.lineBreakMode]; 
    //adjust the label the the new height. 
    CGRect newFrame = alabel.frame; 
    newFrame.size.height = expectedLabelSize.height+40; 
    newFrame.size.width = expectedLabelSize.width+40; 
    alabel.frame = newFrame; 
    labelResizableView.frame = newFrame; 
    labelResizableView.contentView = alabel; 
    labelResizableView.delegate = self; 
    [self.view addSubview:labelResizableView]; 
}

当用户水龙头标签然后

- (void)labelTap:(UITapGestureRecognizer *)tapGesture { 
    ChildViewController *childViewController = [[ChildViewController alloc] initWithNibName:@"ChildViewController" bundle:[NSBundle mainBundle]]; 
    [self presentModalViewController:childViewController animated:NO]; 
}

和ChildViewCoontroller当用户点击完成按钮，然后

-(IBAction)doneBtn:(id)sender 
{ 
    [adelegate updateLabel]; 
    [self dismissModalViewControllerAnimated:NO]; 
}

回答：

#import <UIKit/UIKit.h> 
#import "childViewController.h" 
@interface ParentViewController : UIViewController<UserResizableViewDelegate,ViewControllerDelegate> 
@property (span, nonatomic) ChildViewController *childViewController; 
@end 
@implementation ParentViewController 
- (void)viewDidLoad 
{ 
    self.childViewController = [[ChildViewController alloc] init]; 
    childViewController.delegate=self; //here it show error that ChildViewController does not have property delegate 
} 
@end