Bug: Budget field empty / budgets not loaded when switching source account

[output42]

Bug Description

When creating a withdrawal transaction, the budget dropdown works correctly
for the pre-configured default source account. When switching to any other
asset account, the budget field is either empty (no budgets listed) or
disappears entirely.

Steps to Reproduce

1. Open "Add Transaction"
2. Leave the default source account → budget dropdown shows all budgets ✅
3. Change the source account to any other asset account (e.g. C24 Giro,
   PayPal, cash wallet)
4. Budget field is empty or disappears ❌

Expected Behavior

Budgets are not account-specific in Firefly III — all budgets should be
available regardless of which asset account is selected as the source.

Actual Behavior

Budgets only appear when the default source account is selected.
With any other asset account the budget list is empty, or the field
disappears entirely.

Root Cause (suspected)

In lib/pages/transaction.dart, checkTXType() determines the transaction
type via accountsToTransaction(_sourceAccountType, _destinationAccountType).
The budget widget is conditionally shown:

AnimatedHeight(
  child: (_transactionType == .withdrawal)
      ? TransactionBudget(...)
      : const SizedBox.shrink(),
),

The fallback in checkTXType() sets the type to withdrawal when
_sourceAccountType == .assetAccount and destination is unknown:

if (txType == .swaggerGeneratedUnknown &&
    _sourceAccountType == .assetAccount &&
    _destinationAccountType == .swaggerGeneratedUnknown) {
  txType = .withdrawal;
}

_sourceAccountType may not be correctly set to .assetAccount when the
user selects a non-default account from the dropdown — causing the type to
remain unknown and the budget field to be hidden or not populated.

Environment

• Firefly III: fireflyiii/core:latest (self-hosted)
• All affected accounts are of type defaultAsset or cashWalletAsset
• Tested with multiple asset accounts: same result for all non-default accounts

[dreautall]

Hi, thank you for the report, however I can't replicate this at all, could you maybe record a short video please? I can switch asset accounts at will and the field works.

And please no AI in the reply please ;)

[output42]

I'd prefer not to share the video publicly due to personal financial data visible in the app. I can send you a password-protected link privately. Is there a way to reach you directly?

[dreautall]

My mail address is on the play store listing and inside the app in the notification listener area - the one starting with "app@".

I only need the recording of the transaction creation screen, so no financial data should be visible!

[output42]

hey, thanks for the reply. in the meantime i investigated more closely. set up a dummy user with completely fictional data so i could test without real account details being visible.
i can now reproduce it reliably and the original description was a bit misleading: it's not about which account is selected, it's about the act of switching it. any account works fine when the form first loads. as soon as you switch to a different source account the budget autocomplete breaks.

my guess is that the budget widget initializes correctly on form load but doesn't properly handle the account change event. either the autocomplete controller gets already disposed during the rebuild, or the widget that gets briefly swapped out by AnimatedHeight (if _transactionType leaves .withdrawal for a moment during the switch) comes back up without reloading its data.
no video needed i think, but i have the dummy setup ready and can upload quickly if it helps. just let me know.

[dreautall]

Hi, thanks for the follow-up! I still can't reproduce it, the field appears however I change the source account, so a video would help.

A small note, budgets are only available for withdrawals in Firefly III, so the transaction type (the big box between the two accounts) must be set to withdrawal (red arrow down) for the box to be visible - it's hidden in the default state (grey question mark) or any other type (deposit green arrow down, transfer two blue arrows).

[output42]

https://streamable.com/16lsn7
Expires in 2 days
Size is too big for uploading directly

[dreautall]

Thanks for the effort to create a video! There really seems to be a bug which I can reproduce now: the default autocomplete list (all budgets basically) doesn't pop up after changing the account, I'll fix that.

As a workaround, if you type in any letter it'll correctly show suggestions - it's just the first "initial" search that is not appearing, which is indeed confusing.