IB_DESIGNABLE 从不适用于 NSTextFieldCell

Question

我有一个 NSTextFieldCell 子类，在实现中只有这个代码：

- (NSRect)drawingRectForBounds:(NSRect)theRect
{
    // Get the parent's idea of where we should draw
    NSRect newRect = [super drawingRectForBounds:theRect];

    // When the text field is being 
    // edited or selected, we have to turn off the magic because it screws up 
    // the configuration of the field editor.  We sneak around this by 
    // intercepting selectWithFrame and editWithFrame and sneaking a 
    // reduced, centered rect in at the last minute.
    if (mIsEditingOrSelecting == NO)
    {
        // Get our ideal size for current text
        NSSize textSize = [self cellSizeForBounds:theRect];

        // Center that in the proposed rect
        float heightDelta = newRect.size.height - textSize.height;  
        if (heightDelta > 0)
        {
            newRect.size.height -= heightDelta;
            newRect.origin.y += (heightDelta / 2);
        }
    }

    return newRect;
}

在标题上我在@interface 之前有IB_DESIGNABLE

这个类用于在 NSTextField 上垂直居中文本，但文本从不显示在界面生成器上。此类永远不会在界面生成器上呈现。为什么？

Answer 1

很遗憾，IBDESIGNABLE 仅适用于 NSView 和 UIView 的后代。