I'm having trouble customising an UISegmentedControl: I've subclassed it I'm setting it's background for both the selected state and the unselected state like this:
#define kEdgeInsets UIEdgeInsetsMake(18, 18, 18, 18)
UIImage *grayImage = [[UIImage v_imageNamed:#"gray_rect"] resizableImageWithCapInsets:kEdgeInsets];
[self setBackgroundImage:grayImage
forState:UIControlStateNormal
barMetrics:UIBarMetricsDefault];
UIImage *greenImage = [[UIImage v_imageNamed:#"green_rect"] resizableImageWithCapInsets:kEdgeInsets];
[self setBackgroundImage:greenImage
forState:UIControlStateSelected
barMetrics:UIBarMetricsDefault];
[self setTintColor:[UIColor colorWithRed:0.506 green:0.514 blue:0.525 alpha:1.000]];
Where this are the PNGs I'm using
Now, when I execute this code, I get a weird shadow on the segmented control, which is not what we want. This is what the output looks like
Which is very weird, because there is no shadow on the original images, nor does UISegmentedControl add one (as far as I know).
Further checking, I noticed that if I removed the resizableImageWithCapInsets: call, the image looks distorted (as one should expect) but without the shadow.
Any ideas? because I'm literally going mad over this, since I don't have this problem when using resizableImageWithCapInsets: with UIButton
Thanks a lot!
I figured it out.
Turns out the segmented controller's frame is of 44pts height, and the background images was 75ptsx75pts. Since i've set the image's top and bottom inset to 18pts, the OS was taking the image's top and bottom 18pts and resizing it, ignoring the rest. Here is the fun part, since the image has a gradient, the rest of the image is ignored and it the control is colored like that.
In order to use images with vertical gradients you must use a base PNG with the exact same height as your control (http://useyourloaf.com/blog/2012/07/05/customizing-appearance-with-resizable-images.html)
This is what I did, resize the image to 44x44pts and change the insets to UIEdgeInsetsMake(0, 10, 0, 10) denoting that the image can't have to be resized vertically
I am having troubles with implementation if UISlider.
everything else is working fine except that when Slider thumb is at its minimum position it should not show minimum track image at all.
Screen shot of my iPad Simulator is as follows :-
in this picture, the thumb nob is at its minimum position but still it is showing "green minimum Track image" which it shouldn't
is there any way to come around this problem ?
code in my viewDidLoad method is :-
SLDR.continuous=NO;
[SLDR setMinimumTrackImage:[[UIImage imageNamed:#"U14.png"] stretchableImageWithLeftCapWidth:7 topCapHeight:0]forState:UIControlStateNormal];
[SLDR setMaximumTrackImage:[[UIImage imageNamed:#"U31.png"] stretchableImageWithLeftCapWidth:0 topCapHeight:0] forState:UIControlStateNormal];
[SLDR setThumbImage:[UIImage imageNamed:#"U9.png"] forState:UIControlStateNormal];
[SLDR setThumbImage:[UIImage imageNamed:#"U9.png"] forState:UIControlStateHighlighted];
Please tell me what am i missing, Thanks in advance :)
The standard slider thumbImage sits on top of the slider so it covers min positions. Yours is above so the end is exposed. Try creating a new image, by flipping your max image horizontally. Then add a valueCahnged to the slider like this...
- (IBAction)sliderValueChanged:(id)sender{
if (SLDR.value == 0) {
[SLDR setMinimumTrackImage:[[UIImage imageNamed:#"U31-flipped.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:0]forState:UIControlStateNormal];
} else {
[SLDR setMinimumTrackImage:[[UIImage imageNamed:#"U14.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:0]forState:UIControlStateNormal];
}
Hope this helps!
I'm trying to create a UISlider with a custom thumb image. This works fine, but does not work if I disable the slider. Here's my code:
UISlider *slider = [[UISlider alloc]initWithFrame:CGRectMake(130, 10, sliderBG.size.width, sliderBG.size.height)];
slider.enabled = NO;
[slider setThumbImage:thumbCircle forState:UIControlStateHighlighted];
2 questions:
1) It's using the right image when I set state for UIControlStateHighlighted, but not when I set state to UIControlStateDisabled. Why?
2) The thumb image looks transparent. My image is not transparent. Is the UISlider doing this? Any way to get around it?
Thanks!
That is how UISlider work: use a transparent knob to indicate inactivity. If you want one that does not do that, try recreate it yourself using several UIImageView's and following a finger isn't that difficult on iOS.
Try adding:
[slider setThumbImage:thumbCircle forState: UIControlStateDisabled ];
What is the exact size (width, height) of the (default) thumb image for the iOS slider? Is there perhaps some clever way to coax this out of the system (XCode, iOS)?
I tried
int thumbWidth = slider.currentThumbImage.size.width;
which I found here on this site, but it comes back with 0.
Additional question: The Xcode debugger shows this undocumented variable in the UISlider: CGFloat _hitOffset. Does anyone by chance know what it is and what it's for?
What about this? Works for me:
CGRect trackRect = [self trackRectForBounds:self.bounds];
CGRect thumbRect = [self thumbRectForBounds:self.bounds trackRect:trackRect value:0];
CGSize thumbSize = thumbRect.size;
If you want change UISlider appearance then use below method
[[UISlider appearance] setThumbImage:[UIImage imageNamed:#"yoursliderimage.png"] forState:UIControlStateNormal];
as well as below code would change you slider track also
UIImage *white = [UIImage imageNamed:#"16x16white.png"];
[movieTimeControl setMinimumTrackImage:[white stretchableImageWithLeftCapWidth:3.0 topCapHeight:0.0] forState:UIControlStateNormal];
[movieTimeControl setMaximumTrackImage:[white stretchableImageWithLeftCapWidth:3.0 topCapHeight:0.0] forState:UIControlStateNormal];
Aplle HIG document doesn't define any size for UISlider thumb image but it should be under normal image size.
The best way is using a Resizable Image.
But the slider thumb size is 23x23 if you don't want to make the image resizable
There is a session video about UI customization in the WWDC 2012 collection:
https://developer.apple.com/videos/wwdc/2012/?id=216
You might find your answer here. Its about UISlider customization too
Here is the swift 4 version:
yourSlider.setThumbImage(UIImage(named: "Knob"), for: .normal)
firstButton is a UIButton of type Custom. I'm programmatically putting three of them across each cell of a table, thusly:
[firstButton setImage:markImage forState:UIControlStateNormal];
[firstButton setContentMode:UIViewContentModeScaleAspectFit];
[cell.contentView addSubview:firstButton];
Elsewhere, I'm telling it to clipToBounds. What I get is a crop of the center square of the image, rather than an aspect-scaled rendering of it. I've tried this lots of ways, including setting the mode property on firstButton.imageView, which also doesn't seem to work.
I had the same problem. I see this question is a little old, but I want to provide a clear and correct answer to save other folks (like me) some time when it pops up in their search results.
It took me a bit of searching and experimenting, but I found the solution. Simply set the ContentMode of the "hidden" ImageView that is inside the UIButton.
[[firstButton imageView] setContentMode: UIViewContentModeScaleAspectFit];
[firstButton setImage:[UIImage imageNamed:imageName] forState:UIControlStateNormal];
Perhaps that's what Dan Ray was alluding to in his accepted answer, but I suspect not.
If you're dealing with the UIButton's image (as opposed to it's backgroundImage), setting the contentMode on the UIButton itself or on its imageView has no effect (despite what other answers say).
Alternatively do this instead:
self.button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
self.button.contentVerticalAlignment = UIControlContentVerticalAlignmentFill;
Or size your image accordingly.
OR just use a UIImageView (which properly respects contentMode) with a UITapGestureRecognizer attached to it, or a transparent UIButton on top of it.
Rather than setting the contentMode on the button itself, you'll want to set contentHorizontalAlignment and contentVerticalAlignment properties and (crucially) the contentMode for the button's imageView for any kind of aspect fill or fit:
button.contentHorizontalAlignment = .fill
button.contentVerticalAlignment = .fill
button.imageView?.contentMode = .scaleAspectFit
You can also do other things like aligning the button's image to the top. If you don't need an aspect fill or fit, you just can set the alignment by itself:
button.contentVerticalAlignment = .top
After a couple of hours of confusion, here's how I got it to work under iOS 3.2. As dusker mentioned, using setBackgroundImage instead of setImage did the job for me.
CGRect myButtonFrame = CGRectMake(0, 0, 250, 250);
UIImage *myButtonImage = [UIImage imageNamed:#"buttonImage"];
UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
[myButton setBackgroundImage:myButtonImage forState:UIControlStateNormal];
[myButton setFrame: myButtonFrame];
[myButton setContentMode: UIViewContentModeScaleAspectFit];
The answer is to use a UIImageView with all the lovely Content Mode settings you want, and then layer a custom button on top of it. Dumb that you can't do that all in one shot, but it appears that you can't.
These two things (which are quite hard to find initially) will stretch your UIButton image to fit the button size:
one should always try to set such in the Storyboard rather than code.
Found a fix for this. Set the adjustsImageWhenHighlighted property of UIButton to NO.
UIButton *b = [[UIButton alloc] initWithFrame:rect];
[b setImage:image forState:UIControlStateNormal];
[b.imageView setContentMode:UIViewContentModeScaleAspectFill];
[b setAdjustsImageWhenHighlighted:NO];
Hope this helps. Feel free to comment below, I will follow up on any questions that you have.
My answer is similar to Kuba's. I needed my image to be programatically set.
UIImage *image = [[UIImage alloc] initWithContentsOfFile:...];
[button setBackgroundImage:image forState:UIControlStateNormal];
button.imageView.contentMode = UIViewContentModeScaleAspectFill; //this is needed for some reason, won't work without it.
for(UIView *view in button.subviews) {
view.contentMode = UIViewContentModeScaleAspectFill;
}
Only solution which worked for me:
[button setImage:image forState:UIControlStateNormal];
button.imageView.contentMode = UIViewContentModeScaleAspectFill;
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
button.contentVerticalAlignment = UIControlContentVerticalAlignmentFill;
Swift 3
self.firstButton.imageView?.contentMode = .scaleAspectFill
For anyone experiencing this on iOS 15 and Xcode 13, see Matt's answer in this other question.
The behavior of Xcode changed and now defaults UIButtons from the library to the plain style, which prevents the child image from scaling as expected.
Instead of setImage try setBackgroundImage
I believe we have a simple interface builder issue here - apparently the IB ignores any content-mode changes AFTER you have set the image-property.
the solution is as simple: set the content mode, remove previously set image-names (make sure you remove it in all states, default, highlighted etc.), then re-enter the desired image-names in all desired states - et voilà.
I also advice to have a look at the adjustsImageWhenHighlighted UIButton property to avoid weird deformations of the image, when the button is pressed.
In trying to figure this out, my method got a bit hackier as time went on, and I wound up subclassing UIButton and overriding setHighlighted:
For me it works to just knock down the image alpha to .5, because they're on a black background.
However, it only works if I comment out [super setHighlighted:] (where it appears the image-stretchy code is going on), which just doesn't feel like the right way to solve this at all...everything seems to be working fine, though. We'll see how it holds up as I keep working on it.
- (void)setHighlighted:(BOOL)highlight {
if (highlight) {
[self.imageView setAlpha:.5];
} else {
[self.imageView setAlpha:1];
}
// [super setHighlighted:highlight];
}
If anyone looking for answer that work in iOS 6 and iOS 7 and storyboard:
You can set image in your storyboard:
And then:
for(UIView* testId in self.subviews) {
if([testId isKindOfClass:[UIImageView class]])
[testId setContentMode:UIViewContentModeScaleAspectFill];
}
If the UIButton does not seem to listen to the layout constraint settings, do check whether the images are larger than the button size. Always use the #2x and #3x images for retina resolutions.