On watchOS: drag ended animation starts from full previous screen

[didierburton]

Not sure if this is due to a new version of watchOS, but PageScrollState.swift's line 70:
self.pageOffset = 0.0
seems to reset the position of the "previous" page to its origin before doing the animation to the new page.
As a result, the swipe to an adjacent page has sort of a hiccup.
Moving the statement inside the DispatchQueue.main.async block fixes the issue. Lines 69~76 would change as follows:

       withAnimation(.easeInOut(duration: 0.2)) {
            self.selectedPage = newPage
        }
        
        DispatchQueue.main.async {
            self.pageOffset = 0.0
            self.isGestureActive = false
        }

Even so, swipe "end animations" still do seem a little unnatural, probably because the remaining distance--whatever it might be--is always reached in 0.2 second in an .easeInOut animation, which might benefit from being .easeOut only.
Thank you.

[didierburton]

The fix actually needs to consider whether the new page is different:
The code for a natural gesture (with an .easeOut) becomes:

       withAnimation(.easeOut(duration: 0.2)) {
           if (newPage == selectedPage) {
               self.pageOffset = 0.0
           } else {
             self.selectedPage = newPage
           }
       }

And the DispatchQueue block would stay unaffected.

[fredyshox]

Sorry for the delay. It seems to work, I will add your fix into the next release :)

[fredyshox]

Fixed in 1.5.0