Displaying Underlined Text in a Button for iPhone

Introduction

In this article, we will explore how to display underlined text in a button on an iPhone. This can be achieved by using a combination of UILabel and UITapGestureRecognizer. We will also discuss how to call the Mail Composer view when the button is clicked.

Understanding Underline Text

Underline text refers to the visual representation of a word or phrase that is connected by a line at its base. In iOS development, underlined text can be achieved using UILabel with a specific font attribute.

Creating an Underlined Label

To create an underlined label, we need to set the attributedText property of the label to include an underline style. We can do this by creating a custom UITextAttribute subclass and setting its name to NSUnderlineStyle.

#import <UIKit/UIKit.h>

@interface MYLabel : UILabel

- (void)setUnderlinedText:(NSString *)text;

@end

@implementation MYLabel

- (void)setUnderlinedText:(NSString *)text {
    NSDictionary *attributedTextDict = @{
        NSForegroundColorAttributeName: [UIColor blackColor],
        @"NSParagraphStyleAttributeName": [UIFont paragraphStyle],
        NSUnderlineStyleAttributeName: [NSUnderlineStyle singleLine]
    };
    
    self.attributedText = [self.text attributedStringWithAttributes:attributedTextDict];
}

@end

In the above code, we create a custom label class MYLabel and override its setUnderlinedText: method to set the underline style.

Adding Tap Gesture Recognizer

To handle tap gestures on our underlined label, we need to add a UITapGestureRecognizer to the label.

#import <UIKit/UIKit.h>

@interface MYButton : UIButton

- (void)setTapGestureRecognizer:(id<UIGestureRecognizer>)recognizer;

@end

@implementation MYButton

- (void)setTapGestureRecognizer:(id<UIGestureRecognizer>)recognizer {
    self.addGestureRecognizer(recognizer);
}

@end

In the above code, we create a custom button class MYButton and override its setTapGestureRecognizer: method to add the tap gesture recognizer.

Creating Mail Composer View

To call the Mail Composer view when the button is clicked, we can use the following code:

#import <UIKit/UIKit.h>

@interface MYView : UIView

- (void)openMailComposer;

@end

@implementation MYView

- (void)openMailComposer {
    MFMailComposeViewController *mailComposer = [[MFMailComposeViewController alloc] init];
    mailComposer.mailComposeDelegate = self;
    
    [self presentViewController:mailComposer animated:YES completion:nil];
}

@end

In the above code, we create a custom view class MYView and override its openMailComposer: method to present the Mail Composer view.

Conclusion

Displaying underlined text in a button on an iPhone can be achieved using a combination of UILabel, UITapGestureRecognizer, and custom code. In this article, we explored how to create an underlined label and add tap gesture recognizer to it. We also discussed how to call the Mail Composer view when the button is clicked.

Additional Resources

• TTTAttributedLabel: A subclass of UILabel that supports attributed text, including underlined text.
• MFMailComposeViewController Class Reference: The class reference for the Mail Composer view controller.

Troubleshooting

• If you are experiencing issues with displaying underlined text in your button, ensure that the attributedText property is set correctly.
• If you are experiencing issues with tap gesture recognition, ensure that the UITapGestureRecognizer is added correctly to the label.

Last modified on 2024-03-03