AspectFit image inside an UIButton

问题

I have an image looking like this

But it should look like this :

I added the line : cameraUIButton.imageView?.contentMode = .scaleAspectFit

It doesn't works BUT if i click on the button it fit !! What append in swift when you click on the button that recalculate the fit of the image ?

I already tried

        cameraUIButton.setNeedsDisplay()
        cameraUIButton.imageView?.setNeedsDisplay()
        cameraUIButton.imageView?.layoutIfNeeded()
        cameraUIButton.layoutIfNeeded()
        self.view.layoutIfNeeded()

and all in

viewDidLoad()
viewWillAppear()
viewDidAppear()

Nothing do what cliking on the button do, what else could i try ?

回答1:

When you do cameraUIButton.imageView?.contentMode = .scaleAspectFit it ensures that the image is scaled so as to fit the frame of the view, button in this case.

Try cameraUIButton.imageView?.contentMode = .aspectFit it will retain original image and not stretch it.

回答2:

I found the solution !!
You need to add

cameraUIButton.imageView?.adjustsImageSizeForAccessibilityContentSizeCategory = true

So the full code to aspectFit a vector image inside a button is :

cameraUIButton.imageView?.contentMode = .scaleAspectFit
cameraUIButton.imageView?.adjustsImageSizeForAccessibilityContentSizeCategory = true

I don't know why it's not trueby default as it's turned to it if you click on the button or if you animate it.

回答3:

Try this way

button.contentHorizontalAlignment = .fill
button.contentVerticalAlignment = .fill
button.imageView?.contentMode = .scaleAspectFit

回答4:

Go on storyboard give it a fixed width and height
give is horizontal or vertical constraint according to your view.
if you do these step you will get your image, also it will work fine in all device, don't forget to check clipOutOfBounds

来源：https://stackoverflow.com/questions/57904427/aspectfit-image-inside-an-uibutton

标签

ios

swift

uibutton

swift5