ScrollSelection

Select UIBarButtonItems in Navigation Bars by Scrolling Up.

No need for Reachability or awkwardly holding your phone to reach a button in the top corner.

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Quick-Start Guide

In your ViewController's Swift file,

import ScrollSelection

var scrollSelection: ScrollSelection!

override func viewDidLoad() {
    super.viewDidLoad()
    
    scrollSelection = createScrollSelection() 

    scrollView.delegate = self 
    // If you are using tableViews, use `tableView.delegate = self`
    // If you are using textViews, use `textView.delegate = self`
}

Setting up in ScrollView/TextView/TableView Delegate

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    scrollSelection.didScroll()
}

func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
    scrollSelection.didEndDragging()
}

func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
    scrollSelection.didEndDecelerating()
}

Scroll Selection using UIButton/UISearchBar

                                     // Add a search bar to scrollSelection
scrollSelection.selectionSequence = [.searchBar(mySearchBar), 

                                     // Add a custom button
                                     .button(myButton),
                                     
                                     // Default, right and left bar buttons
                                     .rightBarButtons,
                                     .leftBarButtons]

Customisations and Documentation

Note: For updated documentation information, make use of the Quick Help section (or ⌥-click the declaration)

UIViewController Extension (for quick set-up)

Create Scroll Selection

Summary

Set-Up Scroll Selection on this View Controller

Declaration

func createScrollSelection(withOffset offsetMultiplier: CGFloat = 70, 
                           usingStyle style: [ScrollSelection.Style] = ScrollSelection.Style.defaultStyle) -> ScrollSelection

Parameters

• withOffset offsetMultiplier
  • Distance between each button selection
  • Default Value: 70
• usingStyle style
  • Scroll Selection Style. Use ScrollSelection.Style.defaultStyle for default implementation or remove this parameter
  • Default Value: ScrollSelection.Style.defaultStyle
  • Refer to Style for the various style information

Returns

An instance of Scroll Selection that is already set up

Usage

In your viewDidLoad function,

override func viewDidLoad() {
    super.viewDidLoad()
    
    // Default implementation
    scrollSelection = createScrollSelection() 

    // Custom implementation
    scrollSelection = createScrollSelection(withOffset: 70, usingStyle: ScrollSelection.Style.defaultStyle) 
}

Update Bar Buttons

Summary

Update bar buttons with Scroll Selection

Declaration

func updateBarButtons(barButtonSide direction: ScrollSelection.Direction = .all)

Discussion

Call this function whenever a change is made to the navigation bar buttons

Parameters

• barButtonSide direction
  • .left corresponds to the left bar buttons, .right corresponds to the right bar buttons, .all updates all buttons.
  • Default Value: .all
  • Refer to Direction for the various direction information

Usage

After updating left bar button items,

scrollSelection.updateBarButtons(barButtonSide: .left)

UIScrollViewDelegate Implementation

Did Scroll

Summary

Update ScrollSelection when the scrollview scrolls

Declaration

func didScroll()

Discussion

Updates scroll selection by highlighting or removing highlights on corresponding buttons

Usage

To be called in scrollViewDidScroll function that is part of UIScrollViewDelegate

extension ViewController: UIScrollViewDelegate {
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        scrollSelection.didScroll()
    }
}

Did End Dragging

Summary

Update ScrollSelection when user stops dragging scrollView

Declaration

func didEndDragging()

Discussion

Called when scrollView is released (ends dragging) and thus, scroll selection will select the corresponding bar button

Usage

To be called in scrollViewDidEndDragging function that is part of UIScrollViewDelegate

extension ViewController: UIScrollViewDelegate {
    func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
        scrollSelection.didEndDragging()
    }
}

Did End Decelerating

Summary

Update ScrollSelection once the scrollView stops decelerating

Declaration

func didEndDecelerating()

Discussion

Called when scrollView is ends deceerating and thus, scroll selection will reset to original state

Usage

To be called in scrollViewDidEndDecelerating function that is part of UIScrollViewDelegate

extension ViewController: UIScrollViewDelegate {
    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        scrollSelection.didEndDecelerating()
    }
}

Customising ScrollSelection

Offset Multiplier

Summary

Y-Axis offset between selecting buttons

Declaration

var offsetMultiplier: CGFloat!

Discussion

Should be automatically set in by init or the UIViewController Implementation

Scroll View

Summary

Target UIScrollView for Scroll Selection

Declaration

var scrollView: UIScrollView?

Usage

Discussion

Should be automatically set in by init or the UIViewController Implementation

Scroll Selection will ignore all scrollViews except for the targetted one.

Usage

scrollSelection.scrollView = myScrollView

Haptic Style

Summary

Haptic feedback styles

Declaration

var hapticStyle: HapticsStyle = .variableIncreasing

Discussion

It uses .variableIncreasing as default value.

Refer to HapticsStyle for the various styles

Usage

scrollSelection.hapticStyle = .variableIncreasing

Style

Summary

Current scroll selection style

Declaration

var style: [Style]!

Discussion

Should be automatically set in by init or the UIViewController Implementation.

Refer to Scroll Selection Styles for the various styles

Usage

// Using the default style
scrollSelection.style = ScrollSelection.Style.defaultStyle 

// Using a custom style
scrollSelection.style = [.circularHighlight(using: .systemRed, expands: true)]

Scroll Selection Styles

Highlight

Summary

Changes the Button tint color during Scroll Selection

Declaration

public static func highlight(using color: UIColor = UIColor.systemBlue.withAlphaComponent(0.7)) -> Style

Parameters

• using color
  • Color to change to
  • Default Value: .systemBlue with alpha of 0.7

Returns

A scroll selection style

Circular Highlight

Summary

Adds a circular highlight/background to the button that is being selected

Declaration

public static func circularHighlight(using color: UIColor = .systemGray4,
                                     expands: Bool = true, 
                                     fades: Bool = true) -> Style

Parameters

• using color
  • Color of highlight
  • Default Value: .systemGray4 with alpha of 0.7
• expands
  • If true, circular highlights will expand radially to show emphasis on the button as the user scrolls up. Otherwise, it will stay static and the highlight will not expand.
• fades
  • If true, circular highlight background will fade as the user scrolls up. Otherwise, it will jump from one to another, without fading.

Returns

A scroll selection style

Haptic Styles

Normal

Summary

Normal Haptic Style

Declaration

case normal

Discussion

Normal corresponds to UISelectionFeedbackGenerator().selectionChanged(). A more subtle haptic style.

Variable Increasing

Summary

Default style, feedback becomes more pronounced as user scrolls up

Declaration

case variableIncreasing

Discussion

First Button -> Last Button
Weak         -> Strong

Variable Decreasing

Summary

Haptic feedback becomes less pronounced as user scrolls up

Declaration

case variableDecreasing

Discussion

First Button -> Last Button
Strong       -> Weak

Direction

Left

Summary

Update Left Bar Buttons

Declaration

public static let left: Direction = Direction(rawValue: 1 << 0)

Right

Summary

Update Right Bar Buttons

Declaration

public static let right: Direction = Direction(rawValue: 1 << 1)

All

Summary

Update Both Left and Right Bar Buttons

Declaration

public static let all: Direction = [.left, .right]

Activating and Deactivating

Activate

Summary

Activate Scroll Selection

Declaration

func activate()

Deactivate

Summary

Deactivate Scroll Selection

Declaration

func deactivate()