'How to eliminate PDFView "page shadow"?
When an iOS PDFView is added to a UIView, the PDFView's page area adds a shadow-like border. Is there a way to eliminate the shadow?
I know a few messy ways to do this: Extend the bounds off-screen, overlay a white UIView to hide the shadows, or modify the private PDFPageView (to clip-to-bounds). I specifically don't want the bounds offscreen here, and prefer not to get messy with other hacks.
Example attached. (IRS form used for example here; app has nothing to do with the IRS...)
Solution 1:[1]
Update: Apple responded to my Radar that a new property, PDFView.pageShadowsEnabled, has been added to iOS 12, beta 3. This is now the right way to hide the shadow. Hooray!
Pre-iOS 12 info below:
I confirmed with Apple (WWDC 2018 lab) there is no official way to hide the shadow. I was told there's an internal-only method to do this, and asked to file a Radar to expose that method. Radar # 40847614 if anyone wants to dupe.
Meanwhile I'm deep-diving the view hierarchy, and clipping everything to bounds. I don't like it, but it seems to work. The shadow returns on rotation, so I call this both in viewWillAppear and viewWillTransitionToSize.
-(void)removeShadowFromPDFView:(UIView *)view {
//Deep-dive into pdfView and set all views to clipsToBounds = YES
view.clipsToBounds = YES;
if ([view subviews].count == 0) {
//No subviews to examine
return;
}
for (UIView *subview in view.subviews) {
view.clipsToBounds = YES;
[self removeShadowFromView:subview];
}
}
Solution 2:[2]
I had a similar problem with a split view pane. What I did was to examine each view in the sub views, and each of their subviews, also layers, until identified the problem view (took some time). Then I just made that view hidden or opaque.
When I tested for the uiview subclass, I did not hardcore the name but constructed it with a format string so as not to trigger some automated test of my app (which Apple approved).
Solution 3:[3]
In Swift you can disable page shadows using below line of code
pdfView.pageShadowsEnabled = false
Solution 4:[4]
Actually you should change two properties to eliminate any borders appearance
pdfView.pageShadowsEnabled = false (iOS 12+)
pdfView.backgroundColor = .clear
By the way, because content itself has insets, you may shift it instead of changing backgroundColor:
extension UIView {
func removeShadow() {
func shift(_ view: UIView) {
let origin = view.frame.origin
let insets = UIEdgeInsets(
top: -origin.y,
left: -origin.x,
bottom: -origin.y,
right: -origin.x
)
view.frame = view.frame.inset(by: insets)
}
shift(self)
self.subviews.forEach {
shift($0)
$0.removeShadow()
}
}
}
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
Solution | Source |
---|---|
Solution 1 | |
Solution 2 | David H |
Solution 3 | Nazrul Islam |
Solution 4 | Eugene |