SnapToScroll
Drop-in SwiftUI-based container view for horizontal snapping.
example-video.mp4
Getting Started
Using SnapToScroll
is straightforward. There's just three steps.
- Import
SnapToScroll
- Replace
HStack
withHStackSnap
- Add
.snapAlignmentHelper
to your view.
An example:
import SnapToScroll // Step 1
...
HStackSnap(alignment: .center(32)) { // Step 2
ForEach(myModels) { viewModel in
MyView(
selectedIndex: $selectedIndex,
viewModel: viewModel
)
.snapAlignmentHelper(id: viewModel.id) // Step 3
}
}
For more examples, see SnapToScrollDemo/ContentView.swift
.
Configuration
HStackSnap
comes with two customizable properties:
alignment
: The way you'd like your elements to be arranged.leading(CGFloat)
: Aligns your child views to the leading edge ofHStackSnap
. This configuration supports elements of various sizes, so long as they don't take up all available horizontal space (which would extend beyond the screen). Use the value to set the size of the left offset.center(CGFloat)
: Automatically aligns your child view to the center of the screen, using the offset value you've provided. This is accomplished with inside of the.snapAlignmentHelper
which sets the frame width based on the available space. Note that setting your own width elsewhere may produce unexpected layouts.
coordinateSpace
: Option to set custom name for the coordinate space, in the case you're using multipleHStackSnap
s of various sizes. If you use this, set the same value in.snapAlignmentHelper
.
.snapAlignmentHelper
comes with two options as well:
id
: Required. A unique ID for the element.coordinateSpace
: Same as above.
Limitations
HStackSnap
is currently designed to work with static content.
How it Works
At render, HStackSnap
reads the frame data of each child element and calculates the scrollOffset
each element should use. Then, on DragGesture.onEnded
, the nearest snap location is calculated, and the scroll offset is set to this point.
Read through HStackSnap.swift
and Views/HStackSnapCore.swift
for more details.
Credits
Thanks to pixeltrue for the illustrations used in example 2.