GTSheet is a a simple, easy to integrate solution for presenting UIViewController in bottom sheet. We handle all the hard work for you-- transitions, gestures, taps and more are all automatically provided by the library. Styling, however, is intentionally left out, allowing you to integrate your own design language with ease.
github "gametimesf/GTSheet" == 1.0.5
The example project included is a great way to try out the features of GTSheet and experiment with some of the more advanced functionality. You can explore integrations for regular a UIViewController, a UIViewController that includes a UIScrollView, such as a UITableViewController. You can also explore a more complex example, using functionality to present a UIViewController above the bottom sheet.
Getting started is easy. You'll need to conform to at least one protocol on the presented UIViewController. An optional protocol for your presented UIViewController makes presenting a bottom sheet faster and easier.
Implement HalfSheetPresentableProtocol on the UIViewController that you will be presenting in a bottom sheet.
public protocol HalfSheetPresentableProtocol: class {
weak var managedScrollView: UIScrollView? { get }
var dismissMethod: [DismissMethod] { get }
var sheetHeight: CGFloat? { get }
}
public extension HalfSheetPresentableProtocol where Self: UIViewController {
func didUpdateSheetHeight()
}1.) managedScrollView provides a scroll view that will be used to trigger dismissal transitions. For example, a UITableViewController should return it's tableView property here.
2.) dismissMethod provides an array of DismissMethod options, such as .swipe, .tap. You may return all, some, or none of these options. When returning an empty set, you will be responsible for dismissing your own UIViewController.
3.) sheetHeight provides the height you would like your bottom sheet to be. UIScrollView subviews will overflow and scroll as expected. On iOS 11, Safe Area insets are automatically respected for you, and added to the total height you return. All HalfSheetPresentableProtocol conforming UIViewControllers are extended with a didUpdateSheetHeight method, which should be called to let the library know that it needs to adjust the height of your bottom sheet.
Although you can manually instantiate HalfSheetPresentationManager and assign it as your HalfSheetPresentableProtocol's transitioningDelegate, conforming to HalfSheetPresentingProtocol gives your presenting UIViewController several convenience methods for presenting UIViewControllers in a bottom sheet.
public protocol HalfSheetPresentingProtocol: class {
var transitionManager: HalfSheetPresentationManager! { get set }
}
public extension HalfSheetPresentingProtocol where Self: UIViewController {
func presentUsingHalfSheet(_ vc: UIViewController, animated: Bool = true)
@discardableResult func presentUsingHalfSheetInNC(_ vc: UIViewController, animated: Bool = true) -> UINavigationController
}Implement this on your presenting UIViewController to receive a callback when your bottom sheet is dismissed.
Although most styling can be accomplished by using UIAppearance, some advanced changes are simply not possible. This protocol exposes additional styling options that will be handled within the library.
By conforming to this protocol on your presented UIViewController, you are able to provide a UIViewController that will fill the unused space above your bottom sheet.