BetterPicker

An alternative to SwiftUI’s Picker that supports custom styles.

Basic Usage

struct Item: Identifiable {
    let id: Int

    init(id: Int) {
        self.id = id
    }
}

struct ItemLabel: View {
    private let itemId: String

    init(item: Item) {
        self.itemId = item.id
    }

    var body: some View {
        Text("Cell - \(itemId)")
    }
}

struct ItemPicker: View {
    private let items: [Item] = 0..<100
    @State private var selection: Item.ID = 0

    var body: some View {
        BetterPicker(items, selection: $selection, content: ItemLabel.init)
    }
}

Installation

Currently, only Swift Package Manager is supported. Add it as a package via the URL: https://github.com/MFB-Technologies-Inc/swiftui-pick-better.git

or

git@github.com:MFB-Technologies-Inc/swiftui-pick-better.git

Supported Option Types

The options displayed in a picker must conform to Identifiable as that is how they are correlated to the current selection.

Supported Selection Types

Selection values must conform to Hashable. Where T is the selection value for a given selectable item, the selection may be:

• T
• Optional<T>
• K<T> where K: RandomAccessCollection, K.Element == T

Styling

Unlike SwiftUI’s PickerStyle, BetterPicker supports custom styles. The BetterPickerStyle protocol can be implemented to create reusable styles similar to SwiftUI’s ButtonStyle.

BetterPicker currently includes one builtin style PlainInlineBetterPickerStyle which is similar to the default iOS style of items in a vertical list.

StyleBuilder

BetterPicker includes a resultBuilder type StyleBuilder for conditionally applying a style in a familiar way.

Internals

AnyView

BetterPicker does make use of view type erasure with AnyView. This can have side-effects for various things including animations. However, no problems have been encountered so far.

Modification without ViewModifier

BetterPicker does not apply styles through a ViewModifier. Instead, an instance function on the view is used. Therefore, a style can only be applied directly on the instance of a picker. This practice does not exactly align with how SwiftUI is intended to be used. There is potential for this to cause stability problems. However, no problems of this nature have been encountered so far.

Future Improvements

• Add support for selection values that are Equatable without Hashable
• Add support for options that are not Identifiable
• Change to apply styles through a ViewModifier instead of instance function

Example

The package includes an example app in the Example directory with iOS, macOS, tvOS, and watchOS targets. Additionally, the example includes a more sophisticated style, GridBetterPickerStyle.