NSTextField 上的自定义边框答案

【问题标题】：Custom Border on NSTextFieldNSTextField 上的自定义边框
【发布时间】：2019-02-08 11:01:14
【问题描述】：

我想自定义 NSTextFields 的边框。我已经四处搜索，并且相当确定这需要在drawInterior(withFrame:in:) 的 NSTextFieldCell 中完成，但不确定如何。

具体来说，我只想要一个底部边框，比正常的稍厚。

【问题讨论】：

这是你要找的stackoverflow.com/questions/38841251/set-border-for-nstextfield吗？
我见过这个，但如果你尝试并阅读 cmets，这种方法会导致一大堆其他问题。

【解决方案1】：

您可能应该阅读NSCell 的文档。它说您必须在draw(withFrame:in) 函数中绘制边框，如果您覆盖draw(withFrame:in)，则必须调用drawInterior(withFrame:in:)。此外，您必须覆盖 cellSize 并返回将新边框考虑在内的适当大小。我将示例更新为完整的解决方案。在Github上创建了一个示例项目

/**
 Creates an custom border, that is just a line underneath the NSTextField.
 */
class CustomBorderTextFieldCell: NSTextFieldCell {
    // How thick should the border be
    let borderThickness: CGFloat = 3

    // Add extra height, to accomodate the underlined border, as the minimum required size for the NSTextField
    override var cellSize: NSSize {
        let originalSize = super.cellSize
        return NSSize(width: originalSize.width, height: originalSize.height + borderThickness)
    }

    // Render the custom border for the NSTextField
    override func draw(withFrame cellFrame: NSRect, in controlView: NSView) {
        // Area that covers the NSTextField itself. That is the total height minus our custom border size.
        let interiorFrame = NSRect(x: 0, y: 0, width: cellFrame.width, height: cellFrame.height - borderThickness)

        let path = NSBezierPath()
        path.lineWidth = borderThickness
        // Line width is at the center of the line.
        path.move(to: NSPoint(x: 0, y: cellFrame.height - (borderThickness / 2)))
        path.line(to: NSPoint(x: cellFrame.width, y: cellFrame.height - (borderThickness / 2)))
        NSColor.black.setStroke()
        path.stroke()

        // Pass in area minus the border thickness in the height
        drawInterior(withFrame: interiorFrame, in: controlView)
    }
}

这是结果

【讨论】：

【解决方案2】：

您可以将文本字段添加为背景图像并将边框样式设置为无。

【讨论】：

【解决方案3】：

将此代码添加到 NSTableHeaderCell

override func draw(withFrame cellFrame: NSRect,
                     in controlView: NSView) {
    let path = NSBezierPath()
    path.lineWidth = borderWidth
    // Line width is at the center of the line.
    path.move(to: NSPoint(x: cellFrame.minX, y: cellFrame.minY))
    path.line(to: NSPoint(x: cellFrame.maxX, y: cellFrame.minY))
    NSColor.black.setStroke()
    path.stroke()

    self.drawInterior(withFrame: cellFrame, in: controlView)
  }

【讨论】：