objective-c - NSTextField 自定义对焦环

Question

是否可以在可编辑的 NSTextField 中绘制自定义对焦环？我搜索了整个网络，但找不到有效的解决方案。我对 NSTextField 进行了子类化并覆盖了“drawFocusRingMask”，但没有任何结果。

我的目标是实现一个像 Mac OS Adressbook 中的聚焦环(在编辑人物时)

Answer 1

NSTextField 子类中的这段代码有效:

- (void)awakeFromNib {
    self.focusRingType = NSFocusRingTypeNone;
}

- (void)drawRect:(NSRect)dirtyRect {
    [super drawRect:dirtyRect];

    BOOL focus = NO;

    //check, if the NSTextField is focused
    id firstResponder = self.window.firstResponder;
    if ([firstResponder isKindOfClass:[NSTextView class]]) {
        NSTextView *textView = (NSTextView*)firstResponder;
        NSClipView *clipView = (NSClipView*)textView.superview;
        NSTextField *textField = (NSTextField*)clipView.superview;
        if (textField == self)
            focus = YES;
    }

    if (focus) {
        NSRect bounds = self.bounds;
        NSRect outerRect = NSMakeRect(bounds.origin.x - 2,
                                      bounds.origin.y - 2,
                                      bounds.size.width + 4,
                                      bounds.size.height + 4);

        NSRect innerRect = NSInsetRect(outerRect, 1, 1);

        NSBezierPath *clipPath = [NSBezierPath bezierPathWithRect:outerRect];
        [clipPath appendBezierPath:[NSBezierPath bezierPathWithRect:innerRect]];

        [clipPath setWindingRule:NSEvenOddWindingRule];
        [clipPath setClip];

        [[NSColor colorWithCalibratedWhite:0.6 alpha:1.0] setFill];
        [[NSBezierPath bezierPathWithRect:outerRect] fill];
    }
}