FUIFilterFormCell

public class FUIFilterFormCell: FUIInlineValidationTableViewCell, FUIPickerFormCell, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout

A UITableViewCell subclass, which allows a user to read or enter a set of values, using a grid of buttons. Commonly used for composing filters.

The developer should set the following properties on the cell, in their implementation of UITableViewDataSource cellForRow(at:) function:

• keyName: The key name of the property.
• value: An array of the selected indexes in the control. Uses the same index as the valueOptions array.
• `valueOptions: A String array, of titles for the buttons in the control

And an onChangeHandler:

• onChangeHandler: a handler closure, which is invoked on changes to the value

Optionally, the developer may provide

• allowsMultipleSelection: Indicates if multiple buttons may be selected simultaneously (true). If false, the control behaves in radio mode. Defaults to true.
• allowsEmptySelection: Indicates if the control allows zero items to be selected (true). If false, then once a value has been selected by the developer or user, taps by the user on the last selected item will be ignored, instead of de-selecting the item. Defaults to true.
• isEditable: Indicates if the cell’s value may be modified. Defaults to true.

The following is an example of usage in an application UITableViewController:

 // optionally, create an array of value option to localized string mappings
  let buttonTitles: [[String: String]] = [["radius": "Distance"], ["price": "Price"], ["rating": "Ratings"], ["avail": "Availability"]]

 // Register FUIFilterFormCell in viewDidLoad() method in the controller.
 override func viewDidLoad() {
     super.viewDidLoad()
     self.tableView.register(FUIFilterFormCell.self, forCellReuseIdentifier: FUIFilterFormCell.reuseIdentifier)
 }

 override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
     let cell = tableView.dequeueReusableCell(withIdentifier: FUIFilterFormCell.reuseIdentifier, for: indexPath) as! FUIFilterFormCell

     cell.valueOptions = buttonTitles.flatMap { $0.map { $0.value }}
     cell.keyName = "Sort By"
     cell.value = [1]
     cell.allowsMultipleSelection = true
     cell.allowsEmptySelection = false

     // MARK:  implement onChangeHandler
     cell.onChangeHandler = { newValue in
        self.applyFilter(forDimensions: newValue)      // here, the cell input is set to a filter function
     }

    return cell
 }