NestedSpinner

Overview

Need an alternative ui control for users to easily select an item? Want to make user experience consistent as an Android Spinner instead of "UIPickView-wise" which uses a spinning-wheel style? NestedSpinner may be a choice for you.

NestedSpinner not only provides a quick way to select one value from a set that works similarly as an Android spinner, but also it allows two levels nested spinner: groupItem which can individually be expanded | collapsed to show | hide its children subItems.

NestedSpinner is written in Swift for iOS, it imitates the implementation of Android Spinner, the key classes include:

• NestedSpinnerView
• NestedSpinnerAnchorView
• NestedSpinnerPopupView
• NestedSpinnerAdapter

Requirements

• Xcode 11.
• Swift 5.
• iOS 9 or higher.

Installation

CocoaPods

NestedSpinner is available through CocoaPods. CocoaPods is a dependency manager for Cocoa projects. You can install it with the following command:

$ gem install cocoapods

To install NestedSpinner into your Xcode project, simply add the following line to your Podfile:

pod 'NestedSpinner'

Then, run the following command:

$ pod install

Usage

Code-less Storyboard Implementation

Create a UIView for the spinner. Set the Custom Class of the UIView to be NestedSpinnerView in the Identity Inspector. Set the Module to NestedSpinner (ignore this step if you've manually added NestedSpinnerView to your project).

Code Implementation

1. First, import:

import NestedSpinner

2. Set data for the adatper, set property dataSource of the NestedSpinnerView you just created to an array data for a normal spinner:

spinner.dataSource = arrayData

or set dataTrees for a nested spinner:

spinner.dataTrees = arrayDataTrees

3. Set property anchorOffset to decide the offset to the position of the anchor view:

spinner.anchorOffset = CGPoint(x: 0, y: spinner.bounds.size.height)

4. Set the closures to handle the actions:

spinner.selectionAction = { index, stringValue, userdata in
    
}

That's it.

Data protocol

1. You can populate your own entity into an array and set to the data adapter, then it will be passed back to your selection clousre as userdata.
2. To show the title value of the groupItem or subItem, the entity you pass to the data adater needs to conforms to data protocol, NestedSpinnerDataSource (for a normal spinner) or NestedSpinnerSubItem (for a nested spinner), class NestedSpinnerItem is the required data entity consumed by the nested data adapter.

Style

NestedSpinner have two built-in styles, Light and Dark. It can also set gloable style for all the components or you can set it individually. Just check the style properties, please look at the proptery of NestedSpinnerView and the class NestedSpinnerStyle(https://github.com/wwwhackcom/NestedSpinner/blob/master/NestedSpinner/Classes/NestedSpinnerStyle.swift) for more details,

Customization

1. Customise your own anchor view, please look at the examples CustomisedSpinnerAnchorViewController(https://github.com/wwwhackcom/NestedSpinner/blob/master/Example/NestedSpinner/Style/CustomisedSpinnerAnchorViewController.swift)

2. Customise your own groupItem cell or subItem xib. please look at the examples for more details

ObjC support

NestedSpinner supports ObjC, please go to the example folder ObjcExample, and run the command

$ pod install

Author

Nick Wang, wwwhackcom@qq.com

License

NestedSpinner is available under the MIT license. See the LICENSE file for more info.