commit 282666f0866775b3559a07ab8e96d847dccd85ff
parent b303592f6c1c36efa37929ac6382c9bc043d9331
Author: Marc Stibane <marc@taler.net>
Date: Fri, 14 Aug 2026 18:02:13 +0200
AI: clamp (against deleted exchange)
Diffstat:
1 file changed, 38 insertions(+), 22 deletions(-)
diff --git a/TalerWallet1/Views/HelperViews/ScopePicker.swift b/TalerWallet1/Views/HelperViews/ScopePicker.swift
@@ -17,6 +17,14 @@ fileprivate func urlOrCurrency(_ balance: Balance) -> String {
balance.scopeInfo.url?.trimURL ?? balance.scopeInfo.currency
}
+/// The selected index is `@State´ resp. a `@Binding´, and thus can outlive the balances
+/// array it indexes into - e.g. when an exchange was deleted while this view is on the
+/// navigation stack. Never subscript `controller.balances´ unchecked.
+fileprivate func safeBalance(_ balances: [Balance], _ index: Int) -> Balance? {
+ balances.indices.contains(index) ? balances[index]
+ : balances.first
+}
+
fileprivate func pickerRow(_ balance: Balance, _ currencyInfo: CurrencyInfo) -> (String, String) {
let formatted = formattedAmount(balance, currencyInfo)
let urlOrCurrency = urlOrCurrency(balance)
@@ -70,8 +78,7 @@ struct ScopePicker: View {
let _ = Self._printChanges()
#endif
let count = controller.balances.count
- if (count > 0) {
- let balance = controller.balances[selected]
+ if let balance = safeBalance(controller.balances, selected) {
let currencyInfo = controller.info(for: balance.scopeInfo, controller.currencyTicker)
let available = balance.available
let availableA11y = available.formatted(currencyInfo, isNegative: false,
@@ -115,7 +122,14 @@ struct ScopePicker: View {
.accessibilityHint(disabled ? EMPTYSTRING : chooseHint)
.task() {
// FIXME: check balance for non-zero and disable-peer-payments
- withAnimation { selected = value }
+ // never hand an out-of-range index to `action´ - the callers subscript
+ // `controller.balances´ with it
+ withAnimation { selected = min(max(value, 0), count - 1) }
+ }
+ .onChange(of: count) { newCount in
+ if selected >= newCount { // balances shrank, e.g. exchange deleted
+ selected = 0
+ }
}
.onChange(of: selected) { newValue in
action(newValue)
@@ -183,7 +197,8 @@ struct ScopeDropDown: View {
let chevron = Image(systemName: CHEVRON_UP) //
let foreColor = disabled ? Color.secondary : Color.primary
let backColor = disabled ? WalletColors().backgroundColor : WalletColors().gray4
- let otherBalances = controller.balances.filter { $0 != controller.balances[selection] }
+ let selectedBalance = safeBalance(controller.balances, selection)
+ let otherBalances = controller.balances.filter { $0 != selectedBalance }
let theList = LazyVStack(spacing: 0) {
ForEach(0..<otherBalances.count, id: \.self) { index in
let balance = otherBalances[index]
@@ -211,28 +226,29 @@ struct ScopeDropDown: View {
}
VStack {
// selected item
- let balance = controller.balances[selection]
- let currencyInfo = controller.info(for: balance.scopeInfo, controller.currencyTicker)
- let noAmount = !showDropdown
- Group {
- if disabled {
- dropDownRow(balance, currencyInfo, noAmount)
- } else {
- Button(action: buttonAction) {
- HStack(alignment: .firstTextBaseline) {
- dropDownRow(balance, currencyInfo, noAmount)
- .accessibilityAddTraits(.isSelected)
- Spacer()
- chevron.rotationEffect(.degrees((showDropdown ? -180 : 0)))
- .accessibilityHidden(true)
+ if let balance = selectedBalance {
+ let currencyInfo = controller.info(for: balance.scopeInfo, controller.currencyTicker)
+ let noAmount = !showDropdown
+ Group {
+ if disabled {
+ dropDownRow(balance, currencyInfo, noAmount)
+ } else {
+ Button(action: buttonAction) {
+ HStack(alignment: .firstTextBaseline) {
+ dropDownRow(balance, currencyInfo, noAmount)
+ .accessibilityAddTraits(.isSelected)
+ Spacer()
+ chevron.rotationEffect(.degrees((showDropdown ? -180 : 0)))
+ .accessibilityHidden(true)
+ }
}
}
}
+ .padding(.vertical, 4)
+ .padding(.horizontal, radius / 2)
+ .frame(maxWidth: .infinity, alignment: .leading)
+// .border(.red)
}
- .padding(.vertical, 4)
- .padding(.horizontal, radius / 2)
- .frame(maxWidth: .infinity, alignment: .leading)
-// .border(.red)
if (showDropdown) {
if #available(iOS 17.0, *) {
let count = controller.balances.count
