染一个NSSegmentedControl..。多么?

Question

在用户可以传递到向导的下一个阶段之前，必须选择一个NSSegmentedControl。我可以禁用next按钮，迫使用户猜测缺少了什么东西，但我想将控件的红色闪现，比如颜色或边框，如果用户按下NEXT而不选择控件上的选项，则会引起注意。

我没有在谷歌上找到一个页面来说明如何做到这一点。在可可里可以这样做吗？我怎样才能在一个NSSegmentedControl中做到这一点？

Answer 1

我在滕博中使用了一个有色分段控件。这里的目的不是提请注意该控件，而是让它与彩色导航条相结合。屏幕截图的右上角。

与其从头开始绘制分段控件，不如将标准实现绘制到NSImage中，然后将其绘制为调色，然后再绘制到视图中。

同样的原则也可以用来引起人们对控制的注意。无论何时更改颜色，都需要调用setNeedsDisplay。

@interface TintedSegmentedCell : NSSegmentedCell
{
    NSMutableDictionary *_frames;
}

@end


@implementation TintedSegmentedControl

@synthesize tintColor = _tintColor;

- (void)dealloc
{
    [_tintColor release], _tintColor = nil;

    [super dealloc];
}

+ (Class)cellClass
{
    return [TintedSegmentedCell class];
}

@end


@implementation TintedSegmentedCell

- (void)drawSegment:(NSInteger)segment inFrame:(NSRect)frame withView:(NSView *)controlView
{
    [_frames setObject:[NSValue valueWithRect:frame] forKey:[NSNumber numberWithInteger:segment]];

    [super drawSegment:segment inFrame:frame withView:controlView];
}

- (void)drawWithFrame:(NSRect)frame inView:(NSView *)view
{
    if ([view isKindOfClass:[TintedSegmentedControl class]]) {
        NSColor *tintColor = [(TintedSegmentedControl*)view tintColor];

        if (tintColor != nil) {
            NSRect bounds = frame;

            bounds.origin.x = 0;
            bounds.origin.y = 0;

            NSSize size = bounds.size;
            NSImage *image = [[[NSImage alloc] initWithSize:size] autorelease];

            NSInteger segmentCount = [self segmentCount];
            NSMutableDictionary *frames = [NSMutableDictionary dictionaryWithCapacity:segmentCount];

            _frames = frames;

            [image lockFocus];
            {
                [super drawWithFrame:bounds inView:view];
            }
            [image unlockFocus];

            NSImage *tintedImage = [[image hh_imageTintedWithColor:[NSColor blackColor]] hh_imageTintedWithColor:tintColor];

            [tintedImage drawInRect:frame fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1.0];

            NSImage *overlayImage = [[[NSImage alloc] initWithSize:size] autorelease];

            [overlayImage lockFocus];
            {
                _frames = nil;

                for (NSInteger segment = 0; segment < segmentCount; segment++) {
                    NSRect frameRect = [[frames objectForKey:[NSNumber numberWithInteger:segment]] rectValue];

                    [self drawSegment:segment inFrame:frameRect withView:view];
                }
            }
            [overlayImage unlockFocus];

            [overlayImage drawInRect:frame fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1.0];

            return;
        }
    }

    [super drawWithFrame:frame inView:view];
}

@end