Language / UI Localization

InstrumentControl supports two interface languages: English and Polish (Polski). You can switch between them at any time without restarting the application.

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Switching the Language

1. Click the About button in the toolbar (the ℹ icon, top-right area)
2. In the About dialog, find the Language drop-down
3. Select English or Polski
4. The entire UI updates instantly — all menus, buttons, labels, and status messages switch to the chosen language

The selection is saved automatically and restored on the next launch.

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Persisted Setting

The language preference is stored in a JSON file:

%LocalAppData%\InstrumentControl\settings.json

Example content:

{ "language": "pl" }

Valid values are "en" (English) and "pl" (Polish). If the file is missing or contains an unknown value, the application defaults to English.

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Default Language

English is the default. On a fresh installation (before any language selection) the app starts in English.

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Developer Notes

Resource Files

UI strings are stored in XAML resource dictionaries under src/InstrumentControl.App/Resources/:

File	Language	Entries
Strings.en.xaml	English	298
Strings.pl.xaml	Polish	298

Each file is a standard WPF ResourceDictionary containing <sys:String> entries:

<!-- Strings.en.xaml (excerpt) -->
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:sys="clr-namespace:System;assembly=mscorlib">
    <sys:String x:Key="Toolbar_AddInstrument">➕ Add Instrument</sys:String>
    <sys:String x:Key="Toolbar_Run">▶ Run</sys:String>
    <sys:String x:Key="DriverDesc_HP34401A">6½-digit digital multimeter</sys:String>
    ...
</ResourceDictionary>

All XAML views bind to string resources with {DynamicResource Key}:

<Button Content="{DynamicResource Toolbar_AddInstrument}" />

Using DynamicResource (instead of StaticResource) is what enables the live switch — WPF re-evaluates all dynamic bindings when the resource dictionary is swapped. C# code that needs a localized string reads it through LocalizationService.Get("Key") (or TryGet, which returns null for missing keys).

Intentionally English-only text

Some strings are kept in English in both language files because they are technical:

• Log tab headers (LogTab_All, LogTab_Sequence, LogTab_VISA, LogTab_Serial, LogTab_Events, LogTab_Instruments, LogTab_Debug) and the log content itself — instrument communication logs are read in English.

Localized instrument descriptions

The driver descriptions shown in the Add Instrument dialog come from DriverDesc_<DriverName> keys (e.g. DriverDesc_HP34401A), one per installed driver, so they switch language with the rest of the UI. If a key is missing, the dialog falls back to the driver's built-in Description property.

LocalizationService

src/InstrumentControl.App/Services/LocalizationService.cs is a singleton that:

• Loads the saved language from settings.json on startup (App.xaml.cs calls LocalizationService.Initialize())
• Swaps App.Current.Resources.MergedDictionaries to the correct Strings.xx.xaml when SetLanguage(code) is called
• Persists the new choice back to settings.json

Adding a Third Language

1. Copy Strings.en.xaml to Strings.xx.xaml (where xx is the BCP 47 language tag, e.g. de for German)
2. Translate all 298 string values (leave the LogTab_* keys in English)
3. In LocalizationService.SetLanguage(), add "xx" to the list of supported codes and map it to the new file path
4. Add the language option to the AboutWindow XAML combo-box items