Criteria for snapshotForExpandingParent being invoked?

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Created Jul ’20

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I've got a collectionList section that has some items that can be expanded, but they need to be done so lazily when the user taps them. (The children of these objects can only be retrieved asynchronously.)

I've given these expandable rows an "outline" disclosure indicator but when the row is tapped neither shouldExpandItem nor snapshotForExpandingParent is being invoked on the sectionSnapshotHandlers of the DataSource.

I notice there's no sample code for this and I'm curious if there's a particular way I need to configure the items in the original section snapshot to enable their expansion.

Answered by J0hn in 618791022

Got it. Looks like using .outlineDisclosure(options: .init(style: .header)) and not just .outlineDisclosure() is the trick that causes the snapshotForExpandingParent to get invoked.

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Answer 1

J0hn OP

Jul ’20

Accepted Answer

Got it. Looks like using .outlineDisclosure(options: .init(style: .header)) and not just .outlineDisclosure() is the trick that causes the snapshotForExpandingParent to get invoked.

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Answer 2

J0hn OP

Jul ’20

Also in Beta 1 there appears to be a bug where tapping a header will not trigger an expansion if the outline view is inside a popover.

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