Provides a powerful SwiftUI sheet replacement with the following features:
- All the features of the built-in
sheetmodifiers, but more robust (tested against Xcode 11.0 beta 5). - Modal support (prevent the user from swiping to dismiss), similar to UIKit's
modalInPresentation) - Support for invoking an action when the user tries to dismiss the sheet when it is modal.
Hopefully Apple will make the default sheet modifiers more robust and will add modal presentation
support as well before the final version of iOS 13.0 is released, so this library becomes obsolete.
First make sure you import the BetterSheet package and initialize UIHostingController with power
sheet support in SceneDelegate.swift:
window.rootViewController = UIHostingController.withBetterSheetSupport(rootView: ContentView())
The basic API for presenting a sheet is similar to SwiftUI's sheet(isPresented:onDismiss:content:)
view modifier. But instead of using sheet you use betterSheet.
For example:
struct ContentView: View {
@State var showDetail = false
var body: some View {
VStack {
Button(action: { self.showDetail = true }) {
Text("Show Detail")
}
}
.betterSheet(isPresented: $showDetail) {
Text("Detail!")
}
}
}For more advanced use-cases there is an API similar to SwiftUI's sheet(item:onDismiss:content:
view modifier available:
struct Fruit {
let name: String
}
extension Fruit: Identifiable {
var id: String {
name
}
}
struct ContentView: View {
let fruits = [Fruit(name: "Apple"), Fruit(name: "Banana"), Fruit(name: "Orange")]
@State var selectedFruit: Fruit? = nil
var body: some View {
List(fruits) { fruit in
Button(action: { self.selectedFruit = fruit }) {
Text(fruit.name)
}
}
.betterSheet(item: $selectedFruit) { fruit in
Text("You selected \(fruit.name)")
}
}
}Just as with the SwiftUI sheet modifier there is an environment value similar to SwiftUI's presentationMode
available which you can use to dismiss a sheet from your own code. The BetterSheet version of this environment value is called
betterSheetPresentationMode.
An example:
struct DetailView: View {
@Environment(\.betterSheetPresentationMode) var presentationMode
var body: some View {
Button(action: { self.presentationMode.value.dismiss() }) {
Text("Dismiss")
}
}
}
struct ContentView: View {
@State var showDetail = false
var body: some View {
VStack {
Button(action: { self.showDetail = true }) {
Text("Show Detail")
}
}
.betterSheet(isPresented: $showDetail) {
DetailView()
}
}
}So far we've only looked at the API that offers similar functionality to the default SwiftUI sheet functionality. BetterSheet however offers some more advanced possibilities for if you don't want the user to simply dismiss your sheet with a swipe gesture.
For example:
struct Fruit {
let name: String
}
extension Fruit: Identifiable {
var id: String {
name
}
}
struct EditView: View {
@Binding var fruits: [Fruit]
let fruit: Fruit?
@State var name: String
@Environment(\.betterSheetPresentationMode) var presentationMode
@State var showDismissActions = false
init(fruits: Binding<[Fruit]>, fruit: Fruit? = nil) {
_fruits = fruits
self.fruit = fruit
_name = State(initialValue: fruit?.name ?? "")
}
var isNew: Bool {
fruit == nil
}
var isValid: Bool {
name.trimmingCharacters(in: .whitespaces).count > 0
}
var isModified: Bool {
if let fruit = fruit, name != fruit.name {
return true
} else if fruit == nil && isValid {
return true
} else {
return false
}
}
var body: some View {
NavigationView {
Form {
HStack {
Text("Name")
TextField("Fruit", text: $name).multilineTextAlignment(.trailing)
}
}
.navigationBarTitle(fruit == nil ? "Add Fruit" : "Edit Fruit")
.navigationBarItems(
leading: Button(action: save) { Text("Save").fontWeight(.bold).disabled(!isValid) },
trailing: Button(action: self.cancel) { Text("Cancel") }
)
.actionSheet(isPresented: $showDismissActions) {
ActionSheet(
title: Text("Select an option"),
message: nil,
buttons: [
.destructive(Text(isNew ? "Discard Fruit" : "Discard Changes"), action: self.cancel),
.default(Text(isNew ? "Add Fruit" : "Save Fruit"), action: self.save),
.cancel()
]
)
}
.betterSheetIsModalInPresentation(isModified)
.onBetterSheetDidAttemptToDismiss {
self.showDismissActions = true
}
}
}
func save() {
guard isValid else { return }
let fruit = Fruit(name: name)
if let index = fruits.firstIndex(where: { $0.id == self.fruit?.id }) {
fruits.remove(at: index)
fruits.insert(fruit, at: index)
} else {
fruits.append(fruit)
}
presentationMode.value.dismiss()
}
func cancel() {
presentationMode.value.dismiss()
}
}
struct ContentView: View {
@State var fruits: [Fruit] = [Fruit(name: "Apple")]
@State var addFruit = false
@State var editFruit: Fruit? = nil
var body: some View {
NavigationView {
List(fruits) { fruit in
Text(fruit.name)
Spacer()
Button(action: { self.editFruit = fruit }) {
Image(systemName: "pencil.circle")
}
}
.listStyle(GroupedListStyle())
.navigationBarTitle("Fruits")
.navigationBarItems(
leading: Button(action: { self.addFruit = true }) { Text("Add") }
)
.betterSheet(isPresented: $addFruit) {
EditView(fruits: self.$fruits)
}
.betterSheet(item: $editFruit) { fruit in
EditView(fruits: self.$fruits, fruit: fruit)
}
}
}
}This project is licensed under the terms of the MIT license. See the LICENSE file.