FormatSegmentedControl

var FormatSegmentedControlLeftCapColors     = nil,
    FormatSegmentedControlCenterColors      = nil,
    FormatSegmentedControlRightCapColors    = nil;

@implementation FormatSegmentedControl : CPSegmentedControl
{
    CPArray _backgroundViews;
}

+ (void)initialize
{
    if (self != [FormatSegmentedControl class])
        return;
    
    // Make sure FormatBar is initialized.
    [FormatBar class];
    
    FormatSegmentedControlLeftCapColors = 
    [
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonLeftImage, FormatBarButtonCenterImage, nil] isVertical:NO]],
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonHighlightedLeftImage, FormatBarButtonHighlightedCenterImage, nil] isVertical:NO]],
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonSelectedLeftImage, FormatBarButtonSelectedCenterImage, nil] isVertical:NO]]
    ];
    
    FormatSegmentedControlCenterColors = 
    [
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonDividerImage, FormatBarButtonCenterImage, nil] isVertical:NO]],
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonDividerImage, FormatBarButtonHighlightedCenterImage, nil] isVertical:NO]],
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonDividerImage, FormatBarButtonSelectedCenterImage, nil] isVertical:NO]]
    ];
    
    FormatSegmentedControlRightCapColors = 
    [
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonDividerImage, FormatBarButtonCenterImage, FormatBarButtonRightImage] isVertical:NO]],
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonDividerImage, FormatBarButtonHighlightedCenterImage, FormatBarButtonHighlightedRightImage] isVertical:NO]],
        [CPColor colorWithPatternImage:[[CPThreePartImage alloc] initWithImageSlices:[FormatBarButtonDividerImage, FormatBarButtonSelectedCenterImage, FormatBarButtonSelectedRightImage] isVertical:NO]]
    ];
}

- (void)drawSegmentBezel:(unsigned)aSegment highlight:(BOOL)shouldHighlight
{
    if (!_backgroundViews)
        _backgroundViews = [];
    
    if (!_backgroundViews[aSegment])
    {
        _backgroundViews[aSegment] = [[CPView alloc] initWithFrame:[self frameForSegment:aSegment]];

        [self addSubview:_backgroundViews[aSegment] positioned:CPWindowBelow relativeTo:nil];
    }
    else
        [_backgroundViews[aSegment] setFrame:[self frameForSegment:aSegment]];
    
    var index = shouldHighlight ? 1 : [self isSelectedForSegment:aSegment] ? 2 : 0;
    
    if (aSegment == 0)
        [_backgroundViews[aSegment] setBackgroundColor:FormatSegmentedControlLeftCapColors[index]];
    else if (aSegment == [self segmentCount] - 1)
        [_backgroundViews[aSegment] setBackgroundColor:FormatSegmentedControlRightCapColors[index]];
    else
        [_backgroundViews[aSegment] setBackgroundColor:FormatSegmentedControlCenterColors[index]];
}

@end

use case

    _styleControl = [[FormatSegmentedControl alloc] initWithFrame:CGRectMake(0.0, 0.0, 0.0, 18.0)];
    
    [_styleControl setTrackingMode:CPSegmentSwitchTrackingSelectAny];
    [_styleControl setSegmentCount:3];
    [_styleControl setAction:@selector(changeTextStyle:)];
    
    [_styleControl setWidth:22.0 forSegment:0];
    [_styleControl setImage:[[CPImage alloc] initWithContentsOfFile:@"http://280slides.com/Editor/Current/Resources/FormatBar/FormattingBold.png" size:CGSizeMake(6, 7)] forSegment:0];
    [_styleControl setTag:0 forSegment:0];
    
    [_styleControl setWidth:22.0 forSegment:1];
    [_styleControl setImage:[[CPImage alloc] initWithContentsOfFile:@"http://280slides.com/Editor/Current/Resources/FormatBar/FormattingItalic.png" size:CGSizeMake(6, 7)] forSegment:1];
    [_styleControl setTag:1 forSegment:1];
    
    [_styleControl setWidth:22.0 forSegment:2];
    [_styleControl setImage:[[CPImage alloc] initWithContentsOfFile:@"http://280slides.com/Editor/Current/Resources/FormatBar/FormattingUnderline.png" size:CGSizeMake(6, 7)] forSegment:2];
    [_styleControl setTag:2 forSegment:2];
    
    [_styleControl setFrameOrigin:CGPointMake(5 , 5)];