Scale UISegmentedControl labels based on width of control

问题

This seems like a no brainer, but I cannot find any way to do this. Basically what I have is a UISegmentedControl with two localized labels using NSLocalizedString. I have set the font size and everything looks great in English and a few other languages. But, in Japanese and other languages the characters are larger and cause the label to be truncated.

self.segmentedControl = [[UISegmentedControl alloc] initWithItems:
                             [NSArray arrayWithObjects:
                              NSLocalizedString(@"Miles", nil).uppercaseString,
                              NSLocalizedString(@"Kilometers", nil).uppercaseString,
                              nil]];
self.segmentedControl.apportionsSegmentWidthsByContent = YES;
self.segmentedControl.selectedSegmentIndex = self.metric ? 1 : 0;
[self.segmentedControl addTarget:self action:@selector(changeMetric:) forControlEvents:UIControlEventValueChanged];
self.segmentedControl.frame = CGRectMake(8, middleHolder.frame.size.height/2+60, progressWidth, 30);
self.segmentedControl.center = CGPointMake(self.view.center.x, self.segmentedControl.center.y);
[self.segmentedControl setTitleTextAttributes:@{
                                                    NSForegroundColorAttributeName: [UIColor whiteColor],
                                                    NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue-UltraLight" size:36]
                                                    } forState:UIControlStateSelected];
[self.segmentedControl setTitleTextAttributes:@{
                                                    NSForegroundColorAttributeName: [[UIColor whiteColor] colorWithAlphaComponent:0.3],
                                                    NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue-UltraLight" size:36]
                                                    } forState:UIControlStateNormal];
self.segmentedControl.tintColor = [UIColor clearColor];
self.segmentedControl.autoresizingMask = UIViewAutoresizingFlexibleWidth;
[middleHolder addSubview:self.segmentedControl];

Is there any way to scale the font size of the label depending on the label width? I realize that these are not normal UILabel's, so there is no adjustsFontSizeToFitWidth property.

回答1:

I'm tackling with the same issue. Here is my solution (a bit rough around the edges):

I subclass the segmented control and then in my subclass, do the following. Hope this helps! (Tested on iOS 7 and 8)

+ (void)setSublabelScale:(UIView *)view {
    for (id subview in view.subviews) {
        if ([subview isKindOfClass:[UILabel class]]) {
            [subview setMinimumScaleFactor:0.5];
            [subview setAdjustsFontSizeToFitWidth:YES];
        } else {
            [MYSegmentedControl setSublabelScale:subview];
        }
    }
}

- (void)layoutSubviews {
    [super layoutSubviews];

    [MYSegmentedControl setSublabelScale:self];
}

回答2:

I found out that NSAttributedString has a size property to it, that will allow me to know how wide the text is for every local. So, I can just do something like:

CGFloat fontSize = 36;
NSAttributedString* attributedString = [[NSAttributedString alloc] initWithString:NSLocalizedString(@"Kilometers", nil).uppercaseString attributes:@{NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue-UltraLight" size:fontSize]}];
if (attributedString.size.width > 200) {
    fontSize = 30;
}

来源：https://stackoverflow.com/questions/26453297/scale-uisegmentedcontrol-labels-based-on-width-of-control

标签

ios

objective-c

uilabel

uisegmentedcontrol

nslocalizedstring