objective-c - 在 NSTextField 中设置文本垂直居中

Question

NSTextField 在一定高度下，如果文字比较小，布局会是这样

文字流到顶部，如何让文字居中这样:

Answer 1

class CustomTextFieldCell: NSTextFieldCell {

    func adjustedFrame(toVerticallyCenterText rect: NSRect) -> NSRect {
        // super would normally draw text at the top of the cell
        var titleRect = super.titleRect(forBounds: rect)

        let minimumHeight = self.cellSize(forBounds: rect).height
        titleRect.origin.y += (titleRect.height - minimumHeight) / 2
        titleRect.size.height = minimumHeight

        return titleRect
    }

    override func edit(withFrame rect: NSRect, in controlView: NSView, editor textObj: NSText, delegate: Any?, event: NSEvent?) {
        super.edit(withFrame: adjustedFrame(toVerticallyCenterText: rect), in: controlView, editor: textObj, delegate: delegate, event: event)
    }

    override func select(withFrame rect: NSRect, in controlView: NSView, editor textObj: NSText, delegate: Any?, start selStart: Int, length selLength: Int) {
        super.select(withFrame: adjustedFrame(toVerticallyCenterText: rect), in: controlView, editor: textObj, delegate: delegate, start: selStart, length: selLength)
    }

    override func drawInterior(withFrame cellFrame: NSRect, in controlView: NSView) {
        super.drawInterior(withFrame: adjustedFrame(toVerticallyCenterText: cellFrame), in: controlView)
    }

    override func draw(withFrame cellFrame: NSRect, in controlView: NSView) {
        super.draw(withFrame: cellFrame, in: controlView)
    }
}