创建NSTextField“label”的示例代码?

In my desktop Mac OS X app, I'd like to programatically create a NSTextField "label" which has the same behavior and properties as a typical label created in Interface Builder.

在我的桌面Mac OS X应用程序中，我想程序化地创建一个NSTextField“label”，它的行为和属性与在Interface Builder中创建的典型标签相同。

I usually use (and very much like) IB, but in this case it must be done programatically.

我通常使用IB(非常类似)，但在这种情况下，它必须以编程方式完成。

Try as I might, I can't seem to find the combination of method calls that will programatically produce the same label-y behavior as a "Label" dragged from the IB View Library palette.

尽我所能，我似乎找不到方法调用的组合，它们会以编程方式产生与从IB视图库选项板中拖出的“Label”行为相同的标记-y行为。

Can anyone provide or point out some example code of how to do this programatically? Thx.

是否有人能提供或指出如何以编程方式执行此操作的示例代码?谢谢。

6 个解决方案

#1

A label is actually an instance of NSTextField, a subclass of NSView. So, since it is a NSView, it has to be added to another view.

标签实际上是NSTextField的实例，NSTextField是NSView的子类。因为它是NSView，它必须被添加到另一个视图中。

Here's a working code:

这里有一个工作代码:

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
    NSTextField *textField;

    textField = [[NSTextField alloc] initWithFrame:NSMakeRect(10, 10, 200, 17)];
    [textField setStringValue:@"My Label"];
    [textField setBezeled:NO];
    [textField setDrawsBackground:NO];
    [textField setEditable:NO];
    [textField setSelectable:NO];
    [view addSubview:textField];
}

#2

macOS 10.12 and Later

Starting with macOS 10.12 (Sierra), there are three new NSTextField constructors:

从macOS 10.12 (Sierra)开始，有三个新的NSTextField构造函数:

• NSTextField(labelWithString:), which the header file comment says “Creates a non-wrapping, non-editable, non-selectable text field that displays text in the default system font.”

  NSTextField(labelWithString:)，头文件注释说它“创建了一个非包装、不可编辑、不可选择的文本字段，以默认的系统字体显示文本”。

• NSTextField(wrappingLabelWithString:), which the header file comment says “Creates a wrapping, non-editable, selectable text field that displays text in the default system font.”

  NSTextField(wrappingLabelWithString:)，头文件注释说它“创建一个包装、不可编辑、可选择的文本字段，以默认的系统字体显示文本”。

• NSTextField(labelWithAttributedString:), which the header file comment says “Creates a non-editable, non-selectable text field that displays attributed text. The line break mode of this field is determined by the attributed string's NSParagraphStyle attribute.”

  NSTextField(labelWithAttributedString:)，头文件注释说它“创建一个不可编辑的、不可选择的文本字段，显示带属性的文本”。该字段的断行模式由带属性的字符串的NSParagraphStyle属性决定。

I tested the ones that take a plain (non-attributed string), and they create text fields that are similar to, but not precisely the same as, the text fields created in a storyboard or xib.

我测试了使用纯字符串(非带属性字符串)的文本字段，它们创建的文本字段与故事板或xib中创建的文本字段类似，但并不完全相同。

The important difference is that both constructors create a text field with textBackgroundColor (normally pure white) as its background color, while the storyboard text field uses controlColor (normally about 90% white).

重要的区别是，两个构造函数都使用textBackgroundColor(通常是纯白色)作为背景色创建文本字段，而故事板文本字段使用controlColor(通常为90%的白色)。

Unimportantly, both constructors also set their fonts by calling NSFont.systemFont(ofSize: 0) (which produces a different NSFont object than my code below, but they wrap the same underlying Core Text font).

重要的是，两个构造函数都通过调用NSFont来设置字体。systemFont(ofSize: 0)(生成与下面代码不同的NSFont对象，但它们封装了相同的底层核心文本字体)。

The wrappingLabelWithString: constructor sets the field's isSelectable to true. (This is documented in the header file.)

wrappingLabelWithString:构造函数将字段的isselecttrue设置为true。(这在头文件中有记录。)

---

macOS 10.11 and Earlier

I compared four NSTextField instances: one created by dragging a “Label” to a storyboard, another created by dragging a “Wrapping Label” to a storyboard, and two in code. Then I carefully modified properties of the code-created labels until all their properties were exactly the same as the storyboard-created labels. These two methods are the result:

我比较了四个NSTextField实例:一个是通过将“Label”拖拽到故事板中创建的，另一个是通过将“包装标签”拖到故事板中创建的，还有两个是通过代码创建的。然后我仔细地修改了代码创建标签的属性，直到它们的所有属性都与故事板创建的标签完全相同。这两种方法是结果:

extension NSTextField {

    /// Return an `NSTextField` configured exactly like one created by dragging a “Label” into a storyboard.
    class func newLabel() -> NSTextField {
        let label = NSTextField()
        label.isEditable = false
        label.isSelectable = false
        label.textColor = .labelColor
        label.backgroundColor = .controlColor
        label.drawsBackground = false
        label.isBezeled = false
        label.alignment = .natural
        label.font = NSFont.systemFont(ofSize: NSFont.systemFontSize(for: label.controlSize))
        label.lineBreakMode = .byClipping
        label.cell?.isScrollable = true
        label.cell?.wraps = false
        return label
    }

    /// Return an `NSTextField` configured exactly like one created by dragging a “Wrapping Label” into a storyboard.
    class func newWrappingLabel() -> NSTextField {
        let label = newLabel()
        label.lineBreakMode = .byWordWrapping
        label.cell?.isScrollable = false
        label.cell?.wraps = true
        return label
    }

}

If you use one of these methods, don't forget to set your field's frame, or turn off its translatesAutoresizingMaskIntoConstraints and add constraints.

如果您使用其中的一种方法，不要忘记设置字段的框架，或者关闭其translatesautoresizingmaskintoconstraint并添加约束。

---

Here is the code I used to compare the different text fields, in case you want to check:

这里是我用来比较不同文本字段的代码，如果你想检查的话:

import Cocoa

class ViewController: NSViewController {

    @IBOutlet var label: NSTextField!
    @IBOutlet var multilineLabel: NSTextField!

    override func loadView() {
        super.loadView()
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        let codeLabel = NSTextField.newLabel()
        let codeMultilineLabel = NSTextField.newWrappingLabel()

        let labels = [label!, codeLabel, multilineLabel!, codeMultilineLabel]

        for keyPath in [
            "editable",
            "selectable",
            "allowsEditingTextAttributes",
            "importsGraphics",
            "textColor",
            "preferredMaxLayoutWidth",
            "backgroundColor",
            "drawsBackground",
            "bezeled",
            "bezelStyle",
            "bordered",
            "enabled",
            "alignment",
            "font",
            "lineBreakMode",
            "usesSingleLineMode",
            "formatter",
            "baseWritingDirection",
            "allowsExpansionToolTips",
            "controlSize",
            "highlighted",
            "continuous",
            "cell.opaque",
            "cell.controlTint",
            "cell.backgroundStyle",
            "cell.interiorBackgroundStyle",
            "cell.scrollable",
            "cell.truncatesLastVisibleLine",
            "cell.wraps",
            "cell.userInterfaceLayoutDirection"
        ] {
            Swift.print(keyPath + " " + labels.map({ ($0.value(forKeyPath: keyPath) as? NSObject)?.description ?? "nil" }).joined(separator: " "))
        }
    }
}

#3

This can be tricky to get right. I don't have the recipe for an exact replica handy, but when I've been stuck in a similar situation, here's what I do:

这是很难做到的。我手头没有精确复制的配方，但当我陷入类似的情况时，我要做的是:

1. Create a UI element in IB.
2. 在IB中创建一个UI元素。
3. Add an outlet to it from my controller class.
4. 从我的controller类向它添加一个outlet。
5. Break in gdb in awakeFromNib or whatever.
6. 在awakeFromNib或其他地方中断gdb。
7. From the gdb prompt, "p *whateverOutlet" ... this will show you the C struct contents of the label NSTextField that IB set up.
8. 从gdb提示符“p *whateverOutlet”…这将向您显示IB设置的标签NSTextField的C struct内容。

By looking at all the myriad values in there, you can get a lot of guesses about what you're neglecting to set. Usually it ends up being some magic combination of bezel and border settings, that gets you where you want to be.

通过查看里面的无数值，你可以得到很多关于你忽略了什么设置的猜测。

#4

You could try using nib2objc to get all the properties that IB sets

您可以尝试使用nib2objc获取IB设置的所有属性

#5

Specifically, you will want to setBordered:NO, and set the bezel style to whatever that bezel style is which I forgot. Also setEditable:NO, and optionally setSelectable:NO. That should suffice.

具体来说，你需要设置边框样式:不，设置边框样式到我忘记的边框样式。也可以是setEditable:NO，以及可选的setoptions:NO。这应该足够了。

#6

Disassembled AppKit in Objective-C:

拆卸AppKit在objective - c中:

BOOL TMPSierraOrLater() {
    static BOOL result = NO;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        result = [NSProcessInfo.processInfo isOperatingSystemAtLeastVersion:(NSOperatingSystemVersion){ 10, 12, 0 }];
    });
    return result;
}

@implementation NSTextField (TMP)

+ (instancetype)TMP_labelWithString:(NSString *)stringValue {
    if (TMPSierraOrLater()) {
        return [self labelWithString:stringValue];
    }
    NSParameterAssert(stringValue);
    NSTextField *label = [NSTextField TMP_newBaseLabelWithoutTitle];
    label.lineBreakMode = NSLineBreakByClipping;
    label.selectable = NO;
    [label setContentHuggingPriority:(NSLayoutPriorityDefaultLow + 1) forOrientation:NSLayoutConstraintOrientationHorizontal];
    [label setContentHuggingPriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];
    [label setContentCompressionResistancePriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationHorizontal];
    [label setContentCompressionResistancePriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];
    label.stringValue = stringValue;
    [label sizeToFit];
    return label;
}

+ (instancetype)TMP_wrappingLabelWithString:(NSString *)stringValue {
    if (TMPSierraOrLater()) {
        return [self wrappingLabelWithString:stringValue];
    }
    NSParameterAssert(stringValue);
    NSTextField *label = [NSTextField TMP_newBaseLabelWithoutTitle];
    label.lineBreakMode = NSLineBreakByWordWrapping;
    label.selectable = YES;
    [label setContentHuggingPriority:NSLayoutPriorityDefaultLow forOrientation:NSLayoutConstraintOrientationHorizontal];
    [label setContentHuggingPriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];
    [label setContentCompressionResistancePriority:NSLayoutPriorityDefaultLow forOrientation:NSLayoutConstraintOrientationHorizontal];
    [label setContentCompressionResistancePriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];
    label.stringValue = stringValue;
    label.preferredMaxLayoutWidth = 0;
    [label sizeToFit];
    return label;
}

+ (instancetype)TMP_labelWithAttributedString:(NSAttributedString *)attributedStringValue {
    if (CRKSierraOrLater()) {
        return [self labelWithAttributedString:attributedStringValue];
    }
    NSParameterAssert(attributedStringValue);
    NSTextField *label = [NSTextField TMP_newBaseLabelWithoutTitle];
    [label setContentHuggingPriority:NSLayoutPriorityDefaultLow forOrientation:NSLayoutConstraintOrientationHorizontal];
    [label setContentHuggingPriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];
    [label setContentCompressionResistancePriority:NSLayoutPriorityDefaultLow forOrientation:NSLayoutConstraintOrientationHorizontal];
    [label setContentCompressionResistancePriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];
    label.attributedStringValue = attributedStringValue;
    [label sizeToFit];
    return label;
}

#pragma mark - Private API

+ (instancetype)TMP_newBaseLabelWithoutTitle {
    NSTextField *label = [[self alloc] initWithFrame:CGRectZero];
    label.textColor = NSColor.labelColor;
    label.font = [NSFont systemFontOfSize:0.0];
    label.alignment = NSTextAlignmentNatural;
    label.baseWritingDirection = NSWritingDirectionNatural;
    label.userInterfaceLayoutDirection = NSApp.userInterfaceLayoutDirection;
    label.enabled = YES;
    label.bezeled = NO;
    label.bordered = NO;
    label.drawsBackground = NO;
    label.continuous = NO;
    label.editable = NO;
    return label;
}

@end