FloatingPanel

FloatingPanel is a simple and easy-to-use UI component for a new interface introduced in Apple Maps, Shortcuts and Stocks app. The new interface displays the related contents and utilities in parallel as a user wants.

Features
Requirements
Installation
- CocoaPods
- Carthage
Getting Started
Usage
Notes
- FloatingPanelSurfaceView's issue on iOS 10
Author
License

Features

Simple container view controller
Fluid animation and gesture handling
Scroll view tracking
Common UI elements: Grabber handle, Backdrop and Surface rounding corners
2 or 3 anchor positions(full, half, tip)
Layout customization for all trait environments(i.e. Landscape orientation support)
Behavior customization
Free from common issues of Auto Layout and gesture handling

Examples are here.

Examples/Maps like Apple Maps.app.
Examples/Stocks like Apple Stocks.app.

Requirements

FloatingPanel is written in Swift 4.2. Compatible with iOS 10.0+

Installation

CocoaPods

FloatingPanel is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'FloatingPanel'

Carthage

For Carthage, add the following to your Cartfile:

github "scenee/FloatingPanel"

Getting Started

import UIKit
import FloatingPanel

class ViewController: UIViewController, FloatingPanelControllerDelegate {
    var fpc: FloatingPanelController!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Initialize a `FloatingPanelController` object.
        fpc = FloatingPanelController()

        // Assign self as the delegate of the controller.
        fpc.delegate = self // Optional

        // Add a content view controller.
        let contentVC = ContentViewController()
        fpc.show(contentVC, sender: nil)

        // Track a scroll view(or the siblings) in the content view controller.
        fpc.track(scrollView: contentVC.tableView)

        // Add the views managed by the `FloatingPanelController` object to self.view.
        fpc.addPanel(toParent: self)
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        // Remove the views managed by the `FloatingPanelController` object from self.view.
        fpc.removePanelFromParent()
    }
    ...
}

Usage

Customize the layout of a floating panel with `FloatingPanelLayout` protocol

Change the initial position, supported positions and height

class ViewController: UIViewController, FloatingPanelControllerDelegate {
    ...
    func floatingPanel(_ vc: FloatingPanelController, layoutFor newCollection: UITraitCollection) -> FloatingPanelLayout? {
        return MyFloatingPanelLayout()
    }
    ...
}

class MyFloatingPanelLayout: FloatingPanelLayout {
    public var initialPosition: FloatingPanelPosition {
        return .tip
    }
    public var supportedPositions: [FloatingPanelPosition] {
        return [.full, .half, .tip]
    }

    public func insetFor(position: FloatingPanelPosition) -> CGFloat? {
        switch position {
            case .full: return 16.0 # A top inset from safe area
            case .half: return 216.0 # A bottom inset from the safe area
            case .tip: return 44.0 # A bottom inset from the safe area
        }
    }

    func prepareLayout(surfaceView: UIView, in view: UIView) -> [NSLayoutConstraint] {
        return [
            surfaceView.leftAnchor.constraint(equalTo: view.sideLayoutGuide.leftAnchor, constant: 0.0),
            surfaceView.rightAnchor.constraint(equalTo: view.sideLayoutGuide.rightAnchor, constant: 0.0),
        ]
    }
}

Support your landscape layout

class ViewController: UIViewController, FloatingPanelControllerDelegate {
    ...
    func floatingPanel(_ vc: FloatingPanelController, layoutFor newCollection: UITraitCollection) -> FloatingPanelLayout? {
        return (newCollection.verticalSizeClass == .compact) ? FloatingPanelLandscapeLayout() : nil // Returing nil indicates to use the default layout
    }
    ...
}

class FloatingPanelLandscapeLayout: FloatingPanelLayout {
    public var initialPosition: FloatingPanelPosition {
        return .tip
    }
    public var supportedPositions: [FloatingPanelPosition] {
        return [.full, .tip]
    }

    public func insetFor(position: FloatingPanelPosition) -> CGFloat? {
        switch position {
            case .full: return 16.0
            case .tip: return 69.0
            default: return nil
        }
    }

    public func prepareLayout(surfaceView: UIView, in view: UIView) -> [NSLayoutConstraint] {
        return [
            surfaceView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuid.leftAnchor, constant: 8.0),
            surfaceView.widthAnchor.constraint(equalToConstant: 291),
        ]
    }
}

Customize the behavior with `FloatingPanelBehavior` protocol

Modify your floating panel's interaction

class ViewController: UIViewController, FloatingPanelControllerDelegate {
    ...
    func floatingPanel(_ vc: FloatingPanelController, behaviorFor newCollection: UITraitCollection) -> FloatingPanelBehavior? {
        return FloatingPanelStocksBehavior()
    }
    ...
}
...

class FloatingPanelStocksBehavior: FloatingPanelBehavior {
    var velocityThreshold: CGFloat {
        return 15.0
    }

    func interactionAnimator(_ fpc: FloatingPanelController, to targetPosition: FloatingPanelPosition, with velocity: CGVector) -> UIViewPropertyAnimator {
        let damping = self.damping(with: velocity)
        let springTiming = UISpringTimingParameters(dampingRatio: damping, initialVelocity: velocity)
        return UIViewPropertyAnimator(duration: 0.5, timingParameters: springTiming)
    }
    ...
}

Create an additional floating panel for a detail

class ViewController: UIViewController, FloatingPanelControllerDelegate {
    var searchPanelVC: FloatingPanelController!
    var detailPanelVC: FloatingPanelController!

    override func viewDidLoad() {
        // Setup Search panel
        self.searchPanelVC = FloatingPanelController()

        let searchVC = SearchViewController()
        self.searchPanelVC.show(searchVC, sender: nil)
        self.searchPanelVC.track(scrollView: contentVC.tableView)

        self.searchPanelVC.addPanel(toParent: self)

        // Setup Detail panel
        self.detailPanelVC = FloatingPanelController()

        let contentVC = ContentViewController()
        self.detailPanelVC.show(contentVC, sender: nil)
        self.detailPanelVC.track(scrollView: contentVC.scrollView)

        self.detailPanelVC.addPanel(toParent: self)
    }
    ...
}

Move a positon with an animation

In the following example, I move a floating panel to full or half position while opening or closeing a search bar like Apple Maps.

    func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
        ...
        fpc.move(to: .half, animated: true)
    }

    func searchBarTextDidBeginEditing(_ searchBar: UISearchBar) {
        ...
        fpc.move(to: .full, animated: true)
    }

Make your contents correspond with a floating panel behavior

class ViewController: UIViewController, FloatingPanelControllerDelegate {
    ...
    func floatingPanelWillBeginDragging(_ vc: FloatingPanelController) {
        if vc.position == .full {
            searchVC.searchBar.showsCancelButton = false
            searchVC.searchBar.resignFirstResponder()
        }
    }

    func floatingPanelDidEndDragging(_ vc: FloatingPanelController, withVelocity velocity: CGPoint, targetPosition: FloatingPanelPosition) {
        if targetPosition != .full {
            searchVC.hideHeader()
        }
    }
    ...
}

Notes

FloatingPanelSurfaceView's issue on iOS 10

On iOS 10, FloatingPanelSurfaceView.cornerRadius isn't not automatically masked with the top rounded corners because of UIVisualEffectView issue. See https://forums.developer.apple.com/thread/50854. So you need to draw top rounding corners of your content. Here is an example in Examples/Maps.

override func viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()
    if #available(iOS 10, *) {
        visualEffectView.layer.cornerRadius = 9.0
        visualEffectView.clipsToBounds = true
    }
}

If you sets clear color to FloatingPanelSurfaceView.backgrounColor, please note the bottom overflow of your content on bouncing at full position. To prevent it, you need to expand your content. For example, See Example/Maps's Auto Layout settings of UIVisualEffectView in Main.storyborad.

Author

Shin Yamamoto shin@scenee.com

License

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

mihailsalari/FloatingPanel