UISegmentedControl wrong customization handling

Question

I customized the appearance of a UISegmentedControl using the following code:

UIImage *bg = [UIImage imageNamed:@"segment_bg"];
UIImage *bg_sel = [UIImage imageNamed:@"segment_sel"];
UIImage *leftSep = [UIImage imageNamed:@"segment_div_sx"];
UIImage *rightSep = [UIImage imageNamed:@"segment_div_dx"];

UIEdgeInsets selectionInsets = UIEdgeInsetsMake(0, 8, 0, 8);

[self.segmentedControl setBackgroundImage:[bg resizableImageWithCapInsets:UIEdgeInsetsZero]
                        forState:UIControlStateNormal
                      barMetrics:UIBarMetricsDefault];

[self.segmentedControl setBackgroundImage:[bg_sel resizableImageWithCapInsets:selectionInsets]
                        forState:UIControlStateSelected
                      barMetrics:UIBarMetricsDefault];

[self.segmentedControl setBackgroundImage:[bg resizableImageWithCapInsets:UIEdgeInsetsZero]
                        forState:UIControlStateNormal
                      barMetrics:UIBarMetricsDefault];

[self.segmentedControl setDividerImage:[bg resizableImageWithCapInsets:UIEdgeInsetsZero]
          forLeftSegmentState:UIControlStateNormal
            rightSegmentState:UIControlStateNormal
                   barMetrics:UIBarMetricsDefault];

[self.segmentedControl setDividerImage:rightSep
          forLeftSegmentState:UIControlStateSelected
            rightSegmentState:UIControlStateNormal
                   barMetrics:UIBarMetricsDefault];

[self.segmentedControl setDividerImage:leftSep
          forLeftSegmentState:UIControlStateNormal
            rightSegmentState:UIControlStateSelected
                   barMetrics:UIBarMetricsDefault];

Everything looks fine as you can see in the following image, also other segments look good when switching:

correct_image

but when I switch from the third segment to the first, the segment divider is wrong (no rounded corners on the right end, so not the correct divider).

wrong_image

If the segmented control has more segments, this happens always (and only) when switching from the third segment to the first.

I found out that sending the setNeedsLayout message to the UISegmentedControl object after the valueChanged: event corrects the display.

Now, is it something wrong with the way I customized the segmented control, is it a known bug or should I report this as one?

choise choise · Accepted Answer · 2012-09-01T09:53:23

A bit of an ugly workaround but i managed to fix it with the following until apple fixes it itself.

First you need to subclass UISegmentedControl and add the following:

@implementation MJSegmentedControl

- (void)layoutSubviews
{
    [super layoutSubviews];
    NSInteger cachedIndex = self.selectedSegmentIndex;
    self.selectedSegmentIndex = 0;
    self.selectedSegmentIndex = cachedIndex;
}

@end

UISegmentedControl wrong customization handling

1 Answers