UITableViewDelegate and UITableViewDataSource Default Return Values

November 6, 2016 ยท View on GitHub

Below are the list of default return values of UITableViewDelegate and UITableViewDataSource methods that requires one. Defaults values are returned for invalid parameters (e.g. out of bounds indexes) or indexes where the corresponding child doesn't implement the requested methods. These documentation applies for PropagatingTableDelegate and its subclasses, including CascadingRootTableDelegate and CascadingSectionTableDelegate.

PropagatingTableDelegate has propagationMode property, which could be set to .Row or .Section. Every result that applies to .Row mode will apply to CascadingSectionTableDelegate, and .Section will apply to CascadingRootTableDelegate.

UITableViewDataSource methods

  • tableView(_:numberOfRowsInSection:)
    • .Row: Number of childDelegates.
    • .Section: 0.
  • tableView(_:cellForRowAt:)
    • New UITableViewCell instance.
  • numberOfSections(in:)
    • .Row: 0.
    • .Section: Number of childDelegates.
  • tableView(_:titleForHeaderInSection:)
    • nil.
  • tableView(_:canEditRowAt:)
    • false.
  • tableView(_:titleForFooterInSection:)
    • nil.
  • tableView(_:canEditRowAt:)
    • false.
  • tableView(_:canMoveRowAt:)
    • false.

UITableViewDelegate methods

Height support

  • tableView(_:heightForRowAt:)
    • UITableViewAutomaticDimension.
  • tableView(_:heightForHeaderInSection:)
    • CGFloat(0).
  • tableView(_:heightForFooterInSection:)
    • CGFloat(0)
  • tableView(_:estimatedHeightForRowAt:)
    • Corresponding child's tableView(_:heightForRowAt:) result if available, and
    • UITableViewAutomaticDimension if not.
  • tableView(_:estimatedHeightForHeaderInSection:)
    • Corresponding child's tableView(_:heightForHeaderInSection:) result if available, and
    • CGFloat(0) if not.
  • tableView(_:estimatedHeightForFooterInSection:)
    • Corresponding child's tableView(_:heightForFooterInSection:) result if available, and
    • CGFloat(0) if not.
  • tableView(_:viewForHeaderInSection:)
    • nil.
  • tableView(_:viewForFooterInSection:)
    • nil.

Editing

  • tableView(_:editingStyleForRowAt:)
    • UITableViewCellEditingStyle.None.
  • tableView(_:titleForDeleteConfirmationButtonForRowAt:)
    • nil.
  • tableView(_:editActionsForRowAt:)
    • nil.
  • tableView(_:shouldIndentWhileEditingRowAt:)
    • false.

Selection

  • tableView(_:shouldHighlightRowAt:)
    • true.
  • tableView(_:willSelectRowAt:)
    • NSIndexPath parameter that passed on the method call.
  • tableView(_:willDeselectRowAt:)
    • NSIndexPath parameter that passed on the method call.

Copy and Paste

  • tableView(_:shouldShowMenuForRowAt:)
    • false.
  • tableView(_:canPerformAction:forRowAt:withSender:)
    • false.

Focus

  • tableView(_:canFocusRowAt:)
    • false.

Reorder

  • tableView(_:indentationLevelForRowAt:)
    • 0.