Missing UITableViewDiffableDataSource methods for edit/move rows

[bobek-balinek]

Thank you for creating this project, it's become really useful in few of my projects!

However I have noticed few methods from the official UITableViewDiffableDataSource are missing from your implementation:

• func tableView(UITableView, canEditRowAt: IndexPath) -> Bool
• func tableView(UITableView, canMoveRowAt: IndexPath) -> Bool
• func tableView(UITableView, cellForRowAt: IndexPath) -> UITableViewCell
• func tableView(UITableView, commit: UITableViewCell.EditingStyle, forRowAt: IndexPath)
• func tableView(UITableView, moveRowAt: IndexPath, to: IndexPath)

Reference: https://developer.apple.com/documentation/uikit/uitableviewdiffabledatasource

Naturally I'd expect these methods to be open and overridable to be able to construct and apply a new snapshot separately.

Expected Behavior

Subclassing the TableViewDiffableDataSource should allow to override and provide a custom implementation for canEditRowAt/canMoveRowAt protocol methods.

class MyDiffableDataSource: TableViewDiffableDataSource<SectionViewModel, AnyViewModel> {
    func tableView(_: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        return true
    }

    func tableView(_: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
        // Custom implementation
    }
}

Current Behavior

Methods canEditRowAt and commit:editingStyle:forRowAt do not get executed when implemented on a subclass. This is probably because the base class does not provide an open/public default implementations for these.

[tako3]

You can override canEditRowAt, canMoveRowAt , etc by adding @objc annotation:

@objc(tableView:canEditRowAtIndexPath:)
func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool { 
    true 
}

FMI see Stack Overflow Swift 3 ObjC Optional Protocol Method Not Called in Subclass.

[ra1028]

@bobek-balinek

Sorry for my late reply. I’ｍ a bit busy lately, so please feel free to make a pull request!

Until fixed, please do a good workaround by @tako3 .