I want to crop out a portion of a view. I followed this article: "How to mask one UIView using another UIView", and this is my code currently:
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
/// show a green border around the image view's original frame
let backgroundView = UIView(frame: CGRect(x: 50, y: 50, width: 200, height: 300))
backgroundView.layer.borderColor = UIColor.green.cgColor
backgroundView.layer.borderWidth = 4
view.addSubview(backgroundView)
let imageView = UIImageView(frame: CGRect(x: 50, y: 50, width: 200, height: 300))
imageView.image = UIImage(named: "TestImage")
imageView.contentMode = .scaleAspectFill
imageView.clipsToBounds = true
view.addSubview(imageView)
// MARK: - Mask code
let maskView = UIView(frame: CGRect(x: 80, y: 100, width: 100, height: 100))
maskView.backgroundColor = .blue /// ensure opaque
view.addSubview(maskView)
imageView.mask = maskView
}
}
The mask is working fine:
Without mask
With mask
However, I want the parts of the image view that are cropped out to still be there, but just have a lower alpha. This is what it should look like:
I've tried changing maskView.alpha to 0.25, but that just makes the part with the mask be less opaque.
How can I make the cropped-out parts still be there, but just a bit more transparent?
Preferably I don't want to make another view, because eventually I'll be using this on a camera preview layer — an extra view might have a cost on performance.
Edit: matt's answer
I tried adding a subview with a background color with less alpha:
let maskView = UIView(frame: CGRect(x: 0, y: 0, width: 200, height: 300))
maskView.backgroundColor = UIColor.blue.withAlphaComponent(0.3)
let maskView2 = UIView(frame: CGRect(x: 80, y: 100, width: 100, height: 100))
maskView2.backgroundColor = UIColor.blue.withAlphaComponent(1)
maskView2.alpha = 0
maskView.addSubview(maskView2)
imageView.mask = maskView
But this is the result:
It’s all in the transparency of the colors you paint the mask with. (The hues — what we usually think of as color — are irrelevant.) The masking depends upon the degree of transparency. Areas of the mask that are partially transparent will make the masked view be partially transparent.
So make the mask the whole size of the target view, and make the whole mask a partially transparent color, except for the central area which is an opaque color.
I just started an app for iOS in Swift, I'm doing the design programmatically (I mean I'm not using storyboard)
I have a UIButton with an image inside, I would like the image to fill the entire button. Right now it just show the image in my button, but smaller than the button, center in top of the button frame.
My code is :
let buttonLocation = UIButton(frame: CGRect(x: 0, y: 0, width: buttonRoundedSize, height: buttonRoundedSize))
buttonLocation.setImage(UIImage(named: "locate_button"), for: .normal)
buttonLocation.backgroundColor = .white
buttonLocation.layer.cornerRadius = frame.width / 2
buttonLocation.myExtension()
Here are the things I've tried (none of theses worked) :
self.imageEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
self.autoresizingMask = .flexibleWidth
self.autoresizingMask = .flexibleHeight
self.imageView?.contentMode = .scaleAspectFill
If I just put the contentMode line it doesn't work either. The imageView doesn't return nil i've checked..
Thanks!
Set the contentMode of buttonLocation's imageView as scaleAspectFill or scaleToFill to cover the entire frame of button.
let buttonLocation = UIButton(frame: CGRect(x: 0, y: 0, width: 200, height: 500))
buttonLocation.setImage(UIImage(named: "image"), for: .normal)
buttonLocation.backgroundColor = .gray
buttonLocation.layer.cornerRadius = buttonLocation.frame.width / 2
buttonLocation.imageView?.contentMode = .scaleAspectFill //Here........
Example:
Try using below code and remove other properties which are being set for this button :
let buttonLocation = UIButton(frame: CGRect(x: 50, y: 50, width: 100, height: 100))
buttonLocation.setImage(UIImage(named: "cat"), for: .normal)
buttonLocation.backgroundColor = .white
buttonLocation.layer.cornerRadius = 50
buttonLocation.imageView?.contentMode = .scaleAspectFill
buttonLocation.clipsToBounds = true
self.view.addSubview(buttonLocation)
Here make sure that the image which you are setting in the button is larger than the frame of the button. You can change frame and corner radius values in the above code. I just tried with the above code and getting below output.
You can comment if this is not your expected output.
Hope this helps.
Answer on your question: https://stackoverflow.com/a/26263623/3047318
TLDR: set contentMode in viewDidLoad
you need to use setBackgroundImage property instead of setImage.
buttonLocation.setBackgroundImage(UIImage(named: "locate_button"), for: .normal)
Maybe this can help you:
let buttonLocation = UIButton(type: .custom)
buttonLocation.frame = CGRect(x: 0, y: 0, width: buttonRoundedSize, height: buttonRoundedSize)
buttonLocation.setImage(UIImage(named: "locate_button"), for: .normal)
buttonLocation.imageView?.contentMode = .scaleAspectFill
buttonLocation.contentHorizontalAlignment = .fill
buttonLocation.contentVerticalAlignment = .fill
buttonLocation.backgroundColor = .white
buttonLocation.layer.cornerRadius = frame.width / 2
buttonLocation.clipsToBounds = true
You need to add contentHorizontalAlignment and contentVerticalAlignment properties and don't forget set clipsToBounds to true to see the corner raius effect.
I've updated to Xcode 9, and I have a titleView in my NavigationItem created in this way:
let logo = UIImageView(frame: CGRect(x: 0, y: 0, width: 70, height: 25))
logo.image = UIImage.logo
logo.contentMode = .scaleAspectFit
self.navigationItem.titleView = logo
The result is that it doesn't consider anymore the frame height.
we can control the size and position of UINavigationbar titleview. Don't use to set the imageview as titleview directly. in here create a custom UIView and then set the frame as what you need requirement and add the logo as its subview
do like
let supportVie = UIView(frame: CGRect(x: 0, y: 0, width: 70, height: 25))
// Here you can set View width and height as per your requirement for displaying supportVie position in navigationbar
//supportVie.backgroundColor = UIColor.red
let logo = UIImageView(image: UIImage.logo ) //UIImage(named: "SelectAnAlbumTitleLettering")
logo.frame = CGRect(x: 45, y: 5, width: supportVie.frame.size.width, height: supportVie.frame.size.height)
// customize the origin as (45,5) but can pass them as your requirement.
supportVie.addSubview(logo)
//supportVie.contentMode = .center;
navigationItem.titleView = supportVie
I have an UIButton and an UIView where i want to remove bottom border for the button and top border for the view. The image below show an UIButton. When I press this UIButton the UIView will be added as subview (like a dropdown menu), But I want the button and the view merge with each other so it will look like on "box".
I know how to set border width and color:
self.layer.borderWidth = 1
self.layer.borderColor = UIColor(CGColor: "#616366".CGColor).CGColor
But I don't know if it is possible to remove on border line. Hope you guys can help - Thank you
The easiest way is going to be to change your layout a little bit so that rather than adding the UIView as a subview of the UIButton you add them both as siblings to a container view, and draw the border on the container view.
Kind of like this:
let button = UIButton(frame: CGRect(x: 0, y: 0, width: 100, height: 44))
button.setTitle("Button", forState: .Normal)
button.titleLabel?.textColor = UIColor.blackColor()
let container = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 44))
container.addSubview(button)
container.frame = button.frame
container.backgroundColor = UIColor.whiteColor()
container.layer.borderWidth = 5
container.layer.borderColor = UIColor.blackColor().CGColor
let added = UIView(frame:CGRect(x: 0, y: 44, width: 100, height: 200))
added.backgroundColor = UIColor.blueColor()
container.addSubview(added)
container.frame.size.height += added.frame.size.height
XCPlaygroundPage.currentPage.liveView = container
How can I adjust the image size of the UIButton? I am setting the image like this:
[myLikesButton setImage:[UIImage imageNamed:#"icon-heart.png"] forState:UIControlStateNormal];
However this fills up the image to the full button, how do I make the image smaller?
Historic note:
For this now 10+ yr old question, you now typically just set the point size using setPreferredSymbolConfiguration
If I understand correctly what you're trying to do, you need to play with the buttons image edge inset. Something like:
myLikesButton.imageEdgeInsets = UIEdgeInsets(top: 30, left: 30, bottom: 30, right: 30)
Tim's answer is correct, however I wanted to add another suggestion, because in my case there was a simpler solution altogether.
I was looking to set the UIButton image insets because I didn't realize that I could set the content mode on the button's UIImageView, which would have prevented the need to use UIEdgeInsets and hard-coded values altogether. Simply access the underlying imageview on the button and set the content mode:
myButton.imageView.contentMode = UIViewContentModeScaleAspectFit;
See UIButton doesn't listen to content mode setting?
Swift 3
myButton.imageView?.contentMode = .scaleAspectFit
Swift 3:
button.setImage(UIImage(named: "checkmark_white"), for: .normal)
button.contentVerticalAlignment = .fill
button.contentHorizontalAlignment = .fill
button.imageEdgeInsets = UIEdgeInsetsMake(10, 10, 10, 10)
Here is the other solution to scale an imageView of UIButton.
button.imageView?.layer.transform = CATransform3DMakeScale(0.8, 0.8, 0.8)
You can also do that from inteface builder like this.
I think it's helpful.
If your image is too large (and you can't/don't want to just made the image smaller), a combination of the first two answers works great.
addButton.imageView?.contentMode = .scaleAspectFit
addButton.imageEdgeInsets = UIEdgeInsetsMake(15.0, 15.0, 15.0, 5.0)
Unless you get the image insets just right, the image will be skewed without changing the contentMode.
you can use imageEdgeInsets property
The inset or outset margins for the rectangle around the button’s image.
[self.btn setImageEdgeInsets:UIEdgeInsetsMake(6, 6, 6, 6)];
A positive value shrinks, or insets, that edge—moving. A negative value expands, or outsets, that edge.
Heres the Swift version:
myButton.imageEdgeInsets = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
Swift 4
You would need to use these two lines of code, in this specific order. All you need is to change the top and bottom value of the edge insets.
addButton.imageView?.contentMode = .scaleAspectFit
addButton.imageEdgeInsets = UIEdgeInsetsMake(10.0, 0.0, 10.0, 0.0)
Insetting the image works for me, but I also needed the button Type to be Custom and the button Style to be Default. The defaults for a button added in Xcode 13 are System for Type and Plain for Style.
self.imageEdgeInsets = UIEdgeInsets(top: 3.0, left: 3.0, bottom: 3.0, right: 3.0)
If you are using symbolic images for the button, then this solution is better:
button.setPreferredSymbolConfiguration(UIImage.SymbolConfiguration(pointSize: 48), forImageIn: .normal)
With the help of Tim C's answer, I was able to create an extension on UIButton using Swift that allows you to specify the image frame by using the .setImage() function with an extra frame parameter
extension UIButton{
func setImage(image: UIImage?, inFrame frame: CGRect?, forState state: UIControlState){
self.setImage(image, forState: state)
if let frame = frame{
self.imageEdgeInsets = UIEdgeInsets(
top: frame.minY - self.frame.minY,
left: frame.minX - self.frame.minX,
bottom: self.frame.maxY - frame.maxY,
right: self.frame.maxX - frame.maxX
)
}
}
}
Using this, if you wanted to set the frame of a UIButton to CGRectMake(0, 0, 64, 64), and set the image of it to myImage with a frame of CGRectMake(8, 8, 48, 48), you could use
let button: UIButton = UIButton(frame: CGRectMake(0, 0, 64, 64))
button.setImage(
myImage,
inFrame: CGRectMake(8, 8, 48, 48),
forState: UIControlState.Normal
)
When changing icon size with
UIEdgeInsetsMake(top, left, bottom, right), keep in mind button dimensions and the ability of UIEdgeInsetsMake to work with negative values as if they are positive.
Example: Two buttons with height 100 and aspect 1:1.
left.imageEdgeInsets = UIEdgeInsetsMake(40, 0, 40, 0)
right.imageEdgeInsets = UIEdgeInsetsMake(40, 0, 40, 0)
left.imageEdgeInsets = UIEdgeInsetsMake(40, 0, 40, 0)
right.imageEdgeInsets = UIEdgeInsetsMake(45, 0, 45, 0)
left.imageEdgeInsets = UIEdgeInsetsMake(40, 0, 40, 0)
right.imageEdgeInsets = UIEdgeInsetsMake(60, 0, 60, 0)
Examples 1 and 3 are identical since ABS(100 - (40 + 40)) = ABS(100 - (60 + 60))
Updated for Swift > 5
set the size:
button.frame = CGRect(x: 0, y: 0, width: 44, height: 44)
set margins:
button.imageEdgeInsets = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
One approach is to resize the UIImage in code like the following. Note: this code only scales by height, but you can easily adjust the function to scale by width as well.
let targetHeight = CGFloat(28)
let newImage = resizeImage(image: UIImage(named: "Image.png")!, targetHeight: targetHeight)
button.setImage(newImage, for: .normal)
fileprivate func resizeImage(image: UIImage, targetHeight: CGFloat) -> UIImage {
// Get current image size
let size = image.size
// Compute scaled, new size
let heightRatio = targetHeight / size.height
let newSize = CGSize(width: size.width * heightRatio, height: size.height * heightRatio)
let rect = CGRect(x: 0, y: 0, width: newSize.width, height: newSize.height)
// Create new image
UIGraphicsBeginImageContextWithOptions(newSize, false, 0)
image.draw(in: rect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
// Return new image
return newImage!
}
Swift 3
I set myButton width and height to 40 and my padding from EdgeInsetsMake is 15 all sides. I suggest to add a background color to your button to see the actual padding.
myButton.backgroundColor = UIColor.gray // sample color to check padding
myButton.imageView?.contentMode = .scaleAspectFit
myButton.imageEdgeInsets = UIEdgeInsetsMake(15, 15, 15, 15)
Updated for Swift 3
yourButtonName.imageEdgeInsets = UIEdgeInsetsMake(10, 10, 10, 10)
If you don't want to play around with image insets and you are using auto layout (which I assume you do), another solution is to add size constraints to the image view. Make sure the constraints have a priority of 999, otherwise auto layout will complain.
guard let imageView = button.imageView else { return }
let size = CGSize(width: 20, height: 20)
let sizeConstraints = [
imageView.widthAnchor.constraint(equalToConstant: size.width),
imageView.heightAnchor.constraint(equalToConstant: size.height)
]
imageView.translatesAutoresizingMaskIntoConstraints = false
sizeConstraints.forEach { $0.priority = UILayoutPriority(rawValue: priority) }
NSLayoutConstraint.activate(sizeConstraints)
imageView.contentMode = .scaleAspectFit
i think, your image size is also same as button size then you put image in background of the button like :
[myLikesButton setBackgroundImage:[UIImage imageNamed:#"icon-heart.png"] forState:UIControlStateNormal];
you mast have same size of image and button.i hope you understand my point.