How do I scale a UIButton's imageView?
IosUibuttonScaleIos Problem Overview
I created a UIButton instance named "button" with an image using [UIButton setImage:forState:]
. The button.frame is larger than the image's size.
Now I want to scale this button's image smaller. I tried changing button.imageView.frame
, button.imageView.bounds
and button.imageView.contentMode
, but all seem ineffective.
Can anyone help me scale a UIButton
's imageView?
I created the UIButton
like this:
UIButton *button = [[UIButton alloc] init];
[button setImage:image forState:UIControlStateNormal];
I tried to scale the image like this:
button.imageView.contentMode = UIViewContentModeScaleAspectFit;
button.imageView.bounds = CGRectMake(0, 0, 70, 70);
and this:
button.imageView.contentMode = UIViewContentModeScaleAspectFit;
button.imageView.frame = CGRectMake(0, 0, 70, 70);
Ios Solutions
Solution 1 - Ios
For the original poster, here is the solution I found:
commentButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
This will allow your button to scale horizontally. There is a vertical setting as well.
Took me several hours to figure that one out (the naming of the property is very unintuitive) so figured I'd share.
Solution 2 - Ios
I'd faced similar problem, where I've a background Image (one with border) and an image (flag) for a custom button. I wanted flag to be scaled down and in center. I tried changing imageView's attribute but didn't succeed and was seeing this image --
During my experiments, I tried :
button.imageEdgeInsets = UIEdgeInsetsMake(kTop,kLeft,kBottom,kRight)
I achieved expected result as :
Solution 3 - Ios
An Addition Way for config in XIB file. You can choose this option if you want text or image is Scale full fill in UIButton. It's will be the same with code.
UIButton *btn = [UIButton new];
btn.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
btn.contentVerticalAlignment = UIControlContentVerticalAlignmentFill;
Solution 4 - Ios
use
button.contentMode = UIViewContentModeScaleToFill;
not
button.imageView.contentMode = UIViewContentModeScaleAspectFit;
Update:
As @Chris commented, >To get this to work for setImage:forState:, you need to do the following to scale horizontally: myButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
Solution 5 - Ios
UIButton *button= [[UIButton alloc] initWithFrame:CGRectMake(0,0,70,70)];
button.buttonType = UIButtonTypeCustom;
UIImage *buttonImage = [UIImage imageNamed:@"image.png"];
UIImage *stretchableButtonImage = [buttonImage stretchableImageWithLeftCapWidth:12 topCapHeight:0];
[button setBackgroundImage:stretchableButtonImage forState:UIControlStateNormal];
Solution 6 - Ios
I found this solution.
-
Subclass the following methods of
UIButton
-
(id)buttonWithType:(UIButtonType)buttonType { MyButton *toReturn = [super buttonWithType:buttonType]; toReturn.imageView.contentMode = UIViewContentModeScaleAspectFit; return toReturn; }
- (CGRect)imageRectForContentRect:(CGRect)contentRect { return contentRect; }
-
And it works well.
Solution 7 - Ios
Strange, the only combo that worked for me (iOS 5.1) is...
button.imageView.contentMode = UIViewContentModeScaleAspectFit;
and
[button setImage:newImage forState:UIControlStateNormal];
Solution 8 - Ios
I just ran into this same problem, and there's a possible answer in this question:
Essentially, use the backgroundimage property instead, which does get scaled.
Solution 9 - Ios
Just do (From Design OR From Code):
From Design
- Open your xib OR Storyboard.
- Select button
- Inside Attribute Inspector (Right side) > In "Control" section > select last 4th option for both Horizontal and Verical.
[For Point#3: Change Horizontal and vertical Align to UIControlContentHorizontalAlignmentFill and UIControlContentVericalAlignmentFill]
From Code
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
button.contentVerticalAlignment = UIControlContentVerticalAlignmentFill;
Solution 10 - Ios
like this can solve your problem:
+ (UIImage*)resizedImage:(UIImage*)image
{
CGRect frame = CGRectMake(0, 0, 60, 60);
UIGraphicsBeginImageContext(frame.size);
[image drawInRect:frame];
UIImage* resizedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return resizedImage;
}
Solution 11 - Ios
From small test I just did after reading here, depends if you use setImage or setBackgroundImage, both did the same result and strech the image
//for setBackgroundImage
self.imageButton.contentMode = UIViewContentModeScaleAspectFill;
[self.imageButton setBackgroundImage:[UIImage imageNamed:@"imgFileName"] forState:UIControlStateNormal];
//for setImage
self.imageButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
self.imageButton.contentVerticalAlignment = UIControlContentVerticalAlignmentFill;
[self.imageButton setImage:[UIImage imageNamed:@"imgFileName"] forState:UIControlStateNormal];
Solution 12 - Ios
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentFill;
button.contentVerticalAlignment = UIControlContentVerticalAlignmentFill;
Solution 13 - Ios
Storyboard
You must define specific property in Runtime Attributes of Identity inspector – imageView.contentModel
, where you set value relatively to rawValue
position of enum UIViewContentMode
. 1 means scaleAspectFit.
And button's alignment, in Attributes inspector:
Solution 14 - Ios
This will also work, as the backgroundImage automatically scales
[button setBackgroundImage:image forState:UIControlStateNormal];
Solution 15 - Ios
I hope this can help to somebody else:
Swift 3+
button.contentHorizontalAlignment = UIControlContentHorizontalAlignment.fill
button.contentVerticalAlignment = UIControlContentVerticalAlignment.fill
Solution 16 - Ios
from @JosephH
contentHorizontalAlignment = UIControl.ContentHorizontalAlignment.fill contentVerticalAlignment = UIControl.ContentVerticalAlignment.fill
Solution 17 - Ios
I can't get a solution use by _imageView, but I can use a CGContextRef
to solve it. It use the UIGraphicsGetCurrentContext
to get the currentContextRef and draw a image in currentContextRef, and then scale or rotate the image and create a new image. But it's not perfect.
the code:
-(UIImage*) scaleAndRotateImage:(UIImage*)photoimage width:(CGFloat)bounds_width height:(CGFloat)bounds_height;
{
CGImageRef imgRef = photoimage.CGImage;
CGFloat width = CGImageGetWidth(imgRef);
CGFloat height = CGImageGetHeight(imgRef);
CGAffineTransform transform = CGAffineTransformIdentity;
CGRect bounds = CGRectMake(0, 0, width, height);
bounds.size.width = bounds_width;
bounds.size.height = bounds_height;
CGFloat scaleRatio = bounds.size.width / width;
CGFloat scaleRatioheight = bounds.size.height / height;
CGSize imageSize = CGSizeMake(CGImageGetWidth(imgRef), CGImageGetHeight(imgRef));
CGFloat boundHeight;
UIImageOrientation orient = photoimage.imageOrientation;
switch(orient)
{
case UIImageOrientationUp: //EXIF = 1
transform = CGAffineTransformIdentity;
break;
case UIImageOrientationUpMirrored: //EXIF = 2
transform = CGAffineTransformMakeTranslation(imageSize.width, 0.0);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
break;
case UIImageOrientationDown: //EXIF = 3
transform = CGAffineTransformMakeTranslation(imageSize.width, imageSize.height);
transform = CGAffineTransformRotate(transform, M_PI);
break;
case UIImageOrientationDownMirrored: //EXIF = 4
transform = CGAffineTransformMakeTranslation(0.0, imageSize.height);
transform = CGAffineTransformScale(transform, 1.0, -1.0);
break;
case UIImageOrientationLeftMirrored: //EXIF = 5
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(imageSize.height, imageSize.width);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
break;
case UIImageOrientationLeft: //EXIF = 6
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(0.0, imageSize.width);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
break;
case UIImageOrientationRightMirrored: //EXIF = 7
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeScale(-1.0, 1.0);
transform = CGAffineTransformRotate(transform, M_PI / 2.0);
break;
case UIImageOrientationRight: //EXIF = 8
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(imageSize.height, 0.0);
transform = CGAffineTransformRotate(transform, M_PI / 2.0);
break;
default:
[NSException raise:NSInternalInconsistencyException format:@"Invalid?image?orientation"];
break;
}
UIGraphicsBeginImageContext(bounds.size);
CGContextRef context = UIGraphicsGetCurrentContext();
if (orient == UIImageOrientationRight || orient == UIImageOrientationLeft)
{
CGContextScaleCTM(context, -scaleRatio, scaleRatioheight);
CGContextTranslateCTM(context, -height, 0);
}
else
{
CGContextScaleCTM(context, scaleRatio, -scaleRatioheight);
CGContextTranslateCTM(context, 0, -height);
}
CGContextConcatCTM(context, transform);
CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, width, height), imgRef);
UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageCopy;
}
Solution 18 - Ios
Solution 19 - Ios
You can modify imageView by using custom class of UIButton. Please see my answer. https://stackoverflow.com/a/59874762/5693826
Solution 20 - Ios
Every UIButton has one hidden UIImageView of its own. So we have to set the content mode like the way given below...
[[btn imageView] setContentMode: UIViewContentModeScaleAspectFit];
[btn setImage:[UIImage imageNamed:imageName] forState:UIControlStateNormal];