I'd like to perform an action when the EditMode changes.
Specifically, in edit mode, the user can select some items to delete. He normally presses the trash button afterwards. But he may also press Done. When he later presses Edit again, the items that were selected previously are still selected. I would like all items to be cleared.
struct ContentView: View {
@State var isEditMode: EditMode = .inactive
@State var selection = Set<UUID>()
var items = [Item(), Item(), Item(), Item(), Item()]
var body: some View {
NavigationView {
List(selection: $selection) {
ForEach(items) { item in
Text(item.title)
}
}
.navigationBarTitle(Text("Demo"))
.navigationBarItems(
leading: EditButton(),
trailing: addDelButton
)
.environment(\.editMode, self.$isEditMode)
}
}
private var addDelButton: some View {
if isEditMode == .inactive {
return Button(action: reset) {
Image(systemName: "plus")
}
} else {
return Button(action: reset) {
Image(systemName: "trash")
}
}
}
private func reset() {
selection = Set<UUID>()
}
}
Definition of Item:
struct Item: Identifiable {
let id = UUID()
let title: String
static var i = 0
init() {
self.title = "\(Item.i)"
Item.i += 1
}
}
UPDATED for iOS 15.
This solution catches 2 birds with one stone:
Hopes this helps someone else.
struct ContentView: View {
@State var editMode: EditMode = .inactive
@State var selection = Set<UUID>()
@State var items = [Item(), Item(), Item()]
var body: some View {
NavigationView {
List(selection: $selection) {
ForEach(items) { item in
Text(item.title)
}
}
.navigationTitle(Text("Demo"))
.environment(\.editMode, self.$editMode)
.toolbar {
ToolbarItem(placement: .navigationBarLeading) {
editButton
}
ToolbarItem(placement: .navigationBarTrailing) {
addDelButton
}
}
}
}
private var editButton: some View {
Button(action: {
self.editMode.toggle()
self.selection = Set<UUID>()
}) {
Text(self.editMode.title)
}
}
private var addDelButton: some View {
if editMode == .inactive {
return Button(action: addItem) {
Image(systemName: "plus")
}
} else {
return Button(action: deleteItems) {
Image(systemName: "trash")
}
}
}
private func addItem() {
items.append(Item())
}
private func deleteItems() {
for id in selection {
if let index = items.lastIndex(where: { $0.id == id }) {
items.remove(at: index)
}
}
selection = Set<UUID>()
}
}
extension EditMode {
var title: String {
self == .active ? "Done" : "Edit"
}
mutating func toggle() {
self = self == .active ? .inactive : .active
}
}