Objective-c 悬停时为 NSTextField 标签下划线

Question

所以这个问题实际上涉及到2个问题。

• 首先，我以编程方式创建了大约 5 个 NSTextField 标签，我想知道当我悬停标签时如何为它们添加下划线，相应的标签也会下划线？我一直被这个问题困扰，所以我不知道如何去做。我知道大多数人会认为我问下一个问题是疯了，但我这样做确实有我的理由。

• 第二，如何将点击附加到 NSTextField 标签？我不想使用按钮，因为我不希望单击它时背景颜色可见，即使我隐藏边框，单击时仍然可见背景颜色。我环顾四周(stackoverflow.com 和 google)，似乎没有人能回答这两个问题。您可能需要我如何绘制 NSTextField 标签的代码，所以在这里。

  NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:[NSFont fontWithName:@"Helvetica" size:14], NSFontAttributeName,[NSColor lightGrayColor], NSForegroundColorAttributeName, nil];
  NSAttributedString * trashText=[[NSAttributedString alloc] initWithString: @"Trash" attributes: attributes];
  [trashText drawAtPoint:NSMakePoint(20, 500)];
  

更新

添加了更多 Objective-c。

MainWindowController.h

#import <Cocoa/Cocoa.h>

@interface MainWindowController : NSWindowController {
    @private

}
@end

@interface EmailContents : NSView {
    @private
}

@end

@interface SideBar : NSView {
    @private
}

@end

@interface ClickableTextField : NSTextField
@end

MainWindowController.m

#import "MainWindowController.h"
#import "NSAttributedString+Hyperlink.h"

int currentView = 1;

@implementation NSAttributedString (Hyperlink)
+(id)fakeHyperlinkFromString:(NSString*)inString withColor:(NSColor*)color {
    NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString: inString];
    NSRange range = NSMakeRange(0, [attrString length]);
    [attrString beginEditing];
    // make the text appear in color
    [attrString addAttribute:NSForegroundColorAttributeName value:color range:range];
    // make the text appear with an underline
    [attrString addAttribute: NSUnderlineStyleAttributeName value:[NSNumber numberWithInt:NSSingleUnderlineStyle] range:range];
    [attrString endEditing];
    return [attrString autorelease];
}
@end

@implementation SideBar
- (void)drawRect:(NSRect)HTMLContent {
    int height = [[NSScreen mainScreen] frame].size.height;
    if (currentView == 1) {
        NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:[NSFont fontWithName:@"AvenirNext-Regular" size:16], NSFontAttributeName,[NSColor whiteColor], NSForegroundColorAttributeName, nil];
        NSAttributedString * text_one=[[NSAttributedString alloc] initWithString: @"text_one" attributes: attributes];
        //[text_one setAttributedStringValue:[NSAttributedString fakeHyperlinkFromString:@"text_one" withColor:[NSColor whiteColor]]];
        [text_one drawAtPoint:NSMakePoint(20, 600)];
    } else {
        NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:[NSFont fontWithName:@"AvenirNext-UltraLight" size:14], NSFontAttributeName,[NSColor darkGrayColor], NSForegroundColorAttributeName, nil];
        NSAttributedString * text_one=[[NSAttributedString alloc] initWithString: @"text_one" attributes: attributes];   
        [text_one drawAtPoint:NSMakePoint(20, 600)];
    }
    if (currentView == 2) {
        NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:[NSFont fontWithName:@"AvenirNext-Regular" size:16], NSFontAttributeName,[NSColor whiteColor], NSForegroundColorAttributeName, nil];
        NSAttributedString * text_two=[[NSAttributedString alloc] initWithString: @"text_two" attributes: attributes];
        [text_two drawAtPoint:NSMakePoint(20, 575)];
    } else {
        NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:[NSFont fontWithName:@"AvenirNext-UltraLight" size:14], NSFontAttributeName,[NSColor darkGrayColor], NSForegroundColorAttributeName, nil];
        NSAttributedString * text_two=[[NSAttributedString alloc] initWithString: @"text_two" attributes: attributes];
        [text_two drawAtPoint:NSMakePoint(20, 575)];
    }
    ...
}
@end

Answer 1

您可能应该子类化 NSTextField 来实现您想要的。我做到了。

1。下划线

我对 NSAttributedString (NSAttributedString+Hyperlink.m) 做了一个扩展函数

+(id)fakeHyperlinkFromString:(NSString*)inString withColor:(NSColor*)color {

    NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString: inString];
    NSRange range = NSMakeRange(0, [attrString length]);

    [attrString beginEditing];

    // make the text appear in color
    [attrString addAttribute:NSForegroundColorAttributeName value:color range:range];

    // make the text appear with an underline
    [attrString addAttribute: NSUnderlineStyleAttributeName value:[NSNumber numberWithInt:NSSingleUnderlineStyle] range:range];

    [attrString endEditing];

    return [attrString autorelease];
}

然后您可以将标题分配给 NSTextField(标签)，如下所示:

[myTextField setAttributedStringValue:[NSAttributedString fakeHyperlinkFromString:@"Hello world!" withColor:[NSColor blueColor]]];

2。单击 NSTextField -> 发送操作

这里可以使用delegate来执行Selector。在 NSTextField 子类的 h 文件中声明委托(delegate):

@property (assign) IBOutlet id delegate;

与m文件中相应的@synthesize。现在您可以在 IntefaceBuilder(xib 文件)中连接(分配)委托(delegate)。

之后您可以实现 NSTextField 子类的 mouseUp(或 mouseDown)方法:

- (void)mouseUp:(NSEvent *)theEvent {

    [super mouseUp:theEvent];

    // call delegate
    if (delegate != nil && [delegate respondsToSelector:@selector(textFieldWasClicked)] {

        [delegate performSelector:@selector(textFieldWasClicked) withObject:nil];
    }
}

这对我有用。现在你试试。

<小时/>

更新

您应该将 fakeHyperlinkFromString 放入 NSAttributedString+Hyperlink.m 作为 NSAttributedString 的类别。

H 文件:

#import <Foundation/Foundation.h>

@interface NSAttributedString (Hyperlink)

+(id)fakeHyperlinkFromString:(NSString*)inString withColor:(NSColor*)color;

@end

M 文件:

#import "NSAttributedString+Hyperlink.h"

@implementation NSAttributedString (Hyperlink)

+(id)fakeHyperlinkFromString:(NSString*)inString withColor:(NSColor*)color {

    NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString: inString];
    NSRange range = NSMakeRange(0, [attrString length]);

    [attrString beginEditing];

    // make the text appear in color
    [attrString addAttribute:NSForegroundColorAttributeName value:color range:range];

    // make the text appear with an underline
    [attrString addAttribute: NSUnderlineStyleAttributeName value:[NSNumber numberWithInt:NSSingleUnderlineStyle] range:range];

    [attrString endEditing];

    return [attrString autorelease];
}

@end

然后只需在使用 fakeHyperlinkFromString 的地方包含此 NSAttributedString+Hyperlink.h 即可。它通常是一个 Controller (窗口 Controller )。

在此 Controller 中，您应该有一个指向 textField 对象(如果您创建了子类)的指针。这可以通过使用 (assign) 和 IBOutlet 声明 @property、合成它并在 InterfaceBuilder 中连接来完成。