FrymasterBadgeApp/Documentation/AppShell.cs.md

AppShell

Namespace: FrymasterBadgeApp
Base Class: Shell
Purpose: MAUI Shell container responsible for dynamic tab generation, routing, theme switching, and app-level navigation.

🔑 Fields

Name	Type	Access	Description
_db	SqlService	private readonly	Database service.
_printerService	PrinterService	private readonly	Printing service.
_serviceProvider	IServiceProvider	private readonly	DI container for resolving pages.
_isInitialized	bool	private	Prevents duplicate company loading.

🛠 Constructor

AppShell(SqlService db, PrinterService printerService, IServiceProvider serviceProvider)

• Access: public
• Behavior: Registers routes for SettingsPage, CompanyPage, and EmployeePage.

📦 Methods

OnAppearing()

• Access: protected override async void
• Behavior: Ensures LoadCompaniesAsync() runs exactly once when shell becomes visible.

LoadCompaniesAsync()

• Access: private async Task
• Behavior:
  1. Fetches companies on background thread via Task.Run.
  2. Switches to main thread to clear MainTabBar.Items.
  3. If no companies: adds "Setup" tab routing to CompanyPage.
  4. Else: adds ShellContent tab per company routing to EmployeePage_{ID}.
  5. Navigates to first tab using ///{targetRoute} (rebuilds stack).
  6. Falls back to ///InitialSetup on DB failure.

OnManageCompaniesClicked(object sender, EventArgs e)

• Access: public async void
• Behavior: Pushes CompanyPage onto navigation stack.

OnSettingsClicked(object sender, EventArgs e)

• Access: private async void
• Behavior: Pushes SettingsPage onto stack.

OnThemeClicked(object sender, EventArgs e)

• Access: private async void
• Behavior: Displays action sheet (System, Light, Dark). Updates Application.Current.UserAppTheme and persists to Preferences.Default.

OnExitClicked(object sender, EventArgs e)

• Access: private
• Behavior: Calls Application.Current?.Quit().

OnAboutClicked(object sender, EventArgs e)

• Access: private async void
• Behavior: Displays alert: "Frymaster Badge App v1.0".

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Architecture Notes:

• Uses /// route prefix to force full navigation stack rebuild when switching initial tabs.
• Thread-safe UI updates via MainThread.InvokeOnMainThreadAsync.
• Graceful degradation to setup screen on database failure.