悬停时的Objective-c下划线NSTextField标签

Question

所以这个问题实际上涉及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给它们加下划线，相应的标签会加下划线吗？我对此感到困惑，所以我什至不知道如何去做。我知道大多数人会认为我连问下一个问题都疯了，但我确实有这样做的理由。

• 其次，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，即使我隐藏了边框，单击时仍然可以看到背景颜色。我环顾四周（stackoverflow.com 和谷歌），似乎没有人回答这些问题。你可能需要我如何绘制 NSTextField 标签的代码，所以你去吧。

  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

添加了更多的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

你可能应该继承 NSTextField 来实现你想要的。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];
}

然后您可以像这样将标题分配给 NSTextField（标签）：

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

2。点击 NSTextField -> 发送操作

这里你可以使用delegate对其执行Selector。 在 NSTextField 子类的 h 文件中声明委托：

@property (assign) IBOutlet id delegate;

在 m 文件中有对应的 @synthesize。 现在您可以在 IntefaceBuilder（xib 文件）中连接（分配）委托。

之后就可以实现NSTextField子类的mouseUp（或mouseDown）方法了：

- (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。

---

更新

你应该把fakeHyperlinkFromString 放到NSAttributedString+Hyperlink.m 作为NSAttributedString 的一个类别。

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

然后在你使用fakeHyperlinkFromString 的地方包含这个 NSAttributedString+Hyperlink.h。 它通常是一个控制器（窗口控制器）。

在这个控制器中，你应该有一个指向你的 textField 对象的指针（如果你创建了一个子类）。这可以通过将@property 与(assign) 和IBOutlet 一起声明，合成并在InterfaceBuilder 中连接来完成。