When deleting the last added item from a list view in my app a bar chart in a different view crashes my app. If I delete any other item in the list view everything work as expected. I'm using SwiftData in my app.
Does anyone have any idea how I can prevent the app from crashing?
I filter the data in the init to only have the current days data
Chart View
struct ConsumedDrinkChartView: View {
@Environment(\.modelContext) var modelContext
let screenVerticalSizeClass = UIScreen.VerticalSizeClass
var compactScreen: Bool {
return screenVerticalSizeClass == "compact"
}
@State private var chartCalendarUnit: Calendar.Component = .hour
@State private var chartRange: ClosedRange<Date>
@State private var axisValueLabelFormat: Date.FormatStyle
@State private var axisValueLabelCount: Int
@State private var startDate: Date
@State private var endDate: Date
@State private var plotStartPadding: Double = 0
@State private var plotEndPadding: Double = 0
@Binding var selectedTimeFrame:String
@Query var consumedFluids: [ConsumedDrink]
let defaultVolume = DataStore.defaultVolume
init(selectedTimeFrame: Binding<String>, dateRange: ClosedRange<Date>) {
_selectedTimeFrame = selectedTimeFrame
_startDate = State(initialValue: Date().startOfDay)
_endDate = State(initialValue: Date().endOfDay)
let endDate = dateRange.upperBound
let startDate = dateRange.lowerBound
_consumedFluids = Query(filter: #Predicate {
$0.date > startDate && $0.date < endDate
}, sort: \ConsumedDrink.date)
_chartRange = State(initialValue: dateRange)
_axisValueLabelFormat = State(initialValue: .dateTime.hour(.conversationalDefaultDigits(amPM: .narrow)))
_axisValueLabelCount = State(initialValue: 2)
}
var body: some View {
Chart {
ForEach(consumedFluids) { consumedFluid in
BarMark(x: .value("Date", consumedFluid.date, unit: chartCalendarUnit),
y: .value("Fluid Ounces", consumedFluid.drink.amount))
}
.foregroundStyle(.pink)
}
.frame(height: 180)
.padding()
.chartXAxis {
AxisMarks(values: .stride(by: chartCalendarUnit, count: axisValueLabelCount,roundLowerBound: true, roundUpperBound: true)) { _ in
AxisGridLine()
AxisValueLabel(format: axisValueLabelFormat, centered: true)
}
}
.chartXScale(domain: chartRange, range: .plotDimension(startPadding: plotStartPadding, endPadding: plotEndPadding))
.background(RoundedRectangle(cornerRadius: 12).fill(Color(.secondarySystemBackground)))
.onChange(of: selectedTimeFrame) {
selectChartRange()
}
.onChange(of: consumedFluids) {
print("consumedFluids: \(consumedFluids.count)")
}
.onAppear {
selectChartRange()
}
}
func selectChartRange() {
plotStartPadding = 0
plotEndPadding = 0
switch selectedTimeFrame {
case "Day":
startDate = Date().startOfDay
endDate = Date().endOfDay
chartCalendarUnit = .hour
axisValueLabelCount = 2
axisValueLabelFormat = .dateTime.hour(.conversationalDefaultDigits(amPM: .narrow))
case "Week":
startDate = Date().add(days: -7)
chartCalendarUnit = .day
axisValueLabelCount = 1
axisValueLabelFormat = .dateTime.weekday()
case "Month":
startDate = Date().add(days: -30)
chartCalendarUnit = .day
axisValueLabelCount = 2
axisValueLabelFormat = .dateTime.day()
plotStartPadding = 10
plotEndPadding = 10
case "SixMonths":
let endOfMonth = Date().endOfMonth()
startDate = endOfMonth.add(months: -6)
chartCalendarUnit = .month
axisValueLabelCount = 1
axisValueLabelFormat = .dateTime.month()
plotStartPadding = 10
plotEndPadding = 32
case "Year":
let endOfMonth = Date().endOfMonth()
startDate = endOfMonth.add(months: -12)
chartCalendarUnit = .month
axisValueLabelCount = 1
axisValueLabelFormat = .dateTime.month(.narrow)
plotStartPadding = 15
plotEndPadding = 15
default:
chartCalendarUnit = .day
}
chartRange = startDate...endDate
}
}
List View
struct ConsumedDrinkListView: View {
@Environment(\.modelContext) var modelContext
@Query(sort: \ConsumedDrink.date) var dailyConsumedFluids: [ConsumedDrink]
@State private var showingAlert = false
@State private var alertMessage: String = ""
@State private var alertTitle: String = ""
var body: some View {
NavigationStack {
if dailyConsumedFluids.isEmpty {
ContentUnavailableView("No Consumed Drinks", systemImage: "mug.fill", description: Text("Drink some water and stay hydrated."))
} else {
List {
ForEach(dailyConsumedFluids, id: \.self) { consumedDrink in
NavigationLink {
EditConsumedDrinkView(consumedDrink: consumedDrink)
} label: {
ConsumedDrinkRowView(consumedDrink: consumedDrink)
}
.swipeActions{
Button("Delete", systemImage: "trash", role: .destructive) {
deleteConsumedDrink(consumedDrink: consumedDrink)
}
.tint(.red)
}
}
}
.listStyle(.plain)
.alert(isPresented: $showingAlert) {
Alert(title: Text(alertTitle),
message: Text(alertMessage),
dismissButton: .default(Text("OK"))
)
}
}
Text("")
.navigationTitle("Consumed Drinks")
.navigationBarTitleDisplayMode(.inline)
}
}
func deleteConsumedDrink(consumedDrink: ConsumedDrink) {
do {
if modelContext.hasChanges {
print("ConsumedDrinkListView.deleteConsumedDrink")
print("modelContext has Changes. Saving modelContext")
try modelContext.save()
}
try DataStore.deleteConsumedDrink(drink: consumedDrink, modelContext: modelContext)
} catch {
self.alertTitle = "Error deleting consumed drink - \(consumedDrink.drink.name)"
self.alertMessage = error.localizedDescription
self.showingAlert = true
}
}
}