Added mechanism to restore the contextual tabs, when the Window handle is recreated. When a new handle is created, all commands need to be recreated as well.

Information such as the availability of contextual tabs is part of specific commands and is lost when the commands are destroyed.

Author: SaschaSchaefer

Lib/UIRibbon.pas

@@ -216,6 +216,8 @@   TUIRibbon = class(TWinControl, IUIApplication)
     ///These members are used to register for changes within the action manager's image lists. See procedure RegisterForImageChanges.
     fImageChangeLink: TChangeLink;
     fLargeImageChangeLink: TChangeLink;
+    /// When the window handle is destroyed, the commands are as well. When recreating the window handle, we need to keep track of available context tabs, so that we can restore them
+    fStoredContextTabAvailability: TDictionary<Integer, TUIContextAvailability>;
     { IUIApplication }
     function OnViewChanged(ViewId: UInt32; TypeId: _UIViewType;
       const View: IUnknown; Verb: _UIViewVerb; ReasonCode: Int32): HRESULT; stdcall;
@@ -236,6 +238,8 @@   TUIRibbon = class(TWinControl, IUIApplication)
     procedure LoadFramework();
     /// Called during the initialization of the framework. We register a change event handler towards the action manager's image list (in case that roAssignImagesFromActionManager is used)
     procedure RegisterForImageChanges;
+    procedure StoreContextTabAvailability;
+    procedure RestoreContextTabAvailability;
   protected
     procedure CreateWnd(); override;
     procedure DestroyWnd(); override;
@@ -682,6 +686,7 @@ constructor TUIRibbon.Create(AOwner: TComponent);
   FResourceName := 'APPLICATION';
   FCommands := TObjectDictionary<Cardinal, TUICommand>.Create([doOwnsValues]);
   fUseDarkMode := TDarkMode.Never;
+  fStoredContextTabAvailability := TDictionary<Integer, TUIContextAvailability>.Create;
 
   // Ensure the control is used on a TCustomForm.
   ParentForm := GetParentForm(AOwner as TWinControl);
@@ -739,6 +744,7 @@ destructor TUIRibbon.Destroy;
 begin
   FreeAndNil(fImageChangeLink);
   FreeAndNil(fLargeImageChangeLink);
+  FreeAndNil(fStoredContextTabAvailability);
   if roAutoPreserveState in Options then
     SaveRibbonSettings(); // Save quick toolbar, etc.
 
@@ -1248,11 +1254,16 @@ procedure TUIRibbon.CreateWnd;
 begin
   inherited;
   Load;
+  // Check if there are contextual tabs stored that need to be re-activated
+  if fStoredContextTabAvailability.Count > 0 then
+    RestoreContextTabAvailability;
 end;
 
 procedure TUIRibbon.DestroyWnd;
 begin
   inherited;
+  if (csRecreating in ControlState) then
+    StoreContextTabAvailability;
   if Assigned(FFramework) and  FAvailable then
     FFramework.Destroy;
   FFramework := nil;
@@ -1263,6 +1274,30 @@ procedure TUIRibbon.DestroyWnd;
   fLoaded := False;
 end;
 
+procedure TUIRibbon.StoreContextTabAvailability;
+var
+  lCommand: TUICommand;
+begin
+  for lCommand in fCommands.Values do
+  begin
+    if lCommand.CommandType = TUICommandType.ctContext then
+      fStoredContextTabAvailability.Add(lCommand.CommandId, (lCommand as TUICommandContext).Availability);
+  end;
+end;
+
+procedure TUIRibbon.RestoreContextTabAvailability;
+var
+  lCommandID: Integer;
+  lCommand: TUICommand;
+begin
+  for lCommandID in fStoredContextTabAvailability.Keys do
+  begin
+    if Self.TryGetCommand(lCommandId, lCommand) then
+      (lCommand as TUICommandContext).Availability := fStoredContextTabAvailability[lCommandId]
+  end;
+  fStoredContextTabAvailability.Clear;
+end;
+
 function TUIRibbon.LoadRibbonSettings(): boolean;
 var
   lSettingsFileFullPath: string;