I am currently trying to access the height of a view which I previously set anchors for. So for example, I set the left, right, top, and bottom anchors of searchTable
using the following in my ViewController:
searchTable.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
searchTable.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
searchTable.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
searchTable.bottomAnchor.constraint(equalTo: menuBar.topAnchor).isActive = true
searchTable
is an object of a class that I created that inherits from UIView and has a UIImageView in it. I constrain the UIImageView by using the following in the init function:
imageView.topAnchor.constraint(equalTo: topContainer.topAnchor, constant: 10).isActive = true
imageView.leftAnchor.constraint(equalTo: topContainer.leftAnchor, constant: 10).isActive = true
imageView.heightAnchor.constraint(equalTo: self.heightAnchor, multiplier: topContainerMultiplier * imageProfileMultiplier).isActive = true
imageView.widthAnchor.constraint(equalTo: self.heightAnchor, multiplier: topContainerMultiplier * imageProfileMultiplier).isActive = true
where:
let topContainerMultipler: Double = 1 / 7
let imageProfileMultipler: Double = 1 / 5
Inside the init function of searchTable
, I try want to be able to set the corner radius to be half the image size. I tried to use self.frame.height
, self.frame.size.height
, self.bounds.height
and also getting the .constant
value of the self.heightAnchor
constraint, but all returns 0.
I would think that there is a solution to get around this, but I haven't been able to find it.
You are querying the height of your view's frame after defining your constraints, but before layout has actually resolved those constraints into a frame rectangle. One approach would be to call layoutIfNeeded
to force layout to happen immediately, then use view.frame.size.height
. The init method is probably not an appropriate place to do this, as opposed to perhaps inside viewDidLoad
on the controller. Or you might do this in viewDidLayoutSubviews
to recalculate the corner radius every time your view's layout is updated (in which case you won't need layoutIfNeeded
).