docking, set MW event when new widgets are docked

src/ce_main.pas

@@ -316,6 +316,7 @@ type
     fProjActionsLock: boolean;
     procedure updateMainMenuProviders;
     procedure updateFloatingWidgetOnTop(onTop: boolean);
+    procedure widgetDockingChanged(sender: TCEWidget; newState: TWidgetDockingState);
 
     // action provider handling;
     procedure clearActProviderEntries;
@@ -1097,7 +1098,6 @@ begin
   Handled := true;
 end;
 
-//TODO-cdocking: set splitter MW event when a new widget is docked
 procedure TCEMainForm.setSplitterWheelEvent;
 var
   i: integer;
@@ -1122,6 +1122,11 @@ begin
   end;
 end;
 
+procedure TCEMainForm.widgetDockingChanged(sender: TCEWidget; newState: TWidgetDockingState);
+begin
+  setSplitterWheelEvent;
+end;
+
 procedure TCEMainForm.InitDocking;
 var
   i: Integer;
@@ -1148,6 +1153,7 @@ begin
     if not widg.isDockable then continue;
     DockMaster.MakeDockable(widg, true);
     DockMaster.GetAnchorSite(widg).Header.HeaderPosition := adlhpTop;
+    widg.onDockingChanged:= @widgetDockingChanged;
   end;
 
   // load existing or default docking

src/ce_widget.pas

@@ -6,7 +6,7 @@ interface
 
 uses
   Classes, SysUtils, FileUtil, Forms, Controls, ExtCtrls, ActnList, Menus,
-  AnchorDocking, ce_interfaces, ce_dsgncontrols;
+  AnchorDocking, ce_interfaces, ce_dsgncontrols, ce_common;
 
 type
 
@@ -15,6 +15,11 @@ type
    *)
   PTCEWidget = ^TCEWidget;
 
+  TCEWidget = class;
+
+  TWidgetDockingState = (wdsUndocked, wdsDocked);
+  TWidgetDockingChangedEvent = procedure(sender: TCEWidget; newState: TWidgetDockingState) of object;
+
   { TCEWidget }
 
   TCEWidget = class(TForm, ICEContextualActions)
@@ -30,6 +35,7 @@ type
     fUpdaterDelay: TTimer;
     fImperativeUpdateCount: Integer;
     fLoopUpdateCount: Integer;
+    fOnDockingChanged: TWidgetDockingChangedEvent;
     procedure setDelayDur(aValue: Integer);
     procedure setLoopInt(aValue: Integer);
     procedure updaterAutoProc(Sender: TObject);
@@ -39,6 +45,9 @@ type
     fIsModal: boolean;
     fToolBarFlat: boolean;
     fToolBarVisible: boolean;
+    fOldParent: TWinControl;
+    // TODO-cdocking: find a better way to detect that the docking state changed
+    procedure Resize; override;
     // a descendant overrides to implement a periodic update.
     procedure updateLoop; virtual;
     // a descendant overrides to implement an imperative update.
@@ -93,6 +102,7 @@ type
 
     property toolbarFlat: boolean read fToolBarFlat write setToolBarFlat;
     property toolbarVisible: boolean read fToolBarVisible write setToolBarVisible;
+    property onDockingChanged: TWidgetDockingChangedEvent read fOnDockingChanged write fOnDockingChanged;
   end;
 
   (**
@@ -209,6 +219,26 @@ begin
     toolbar.Flat := value;
     fToolBarFlat := value;
 end;
+
+procedure TCEWidget.Resize;
+var
+  newParent: TWinControl;
+  site: TAnchorDockHostSite;
+begin
+  inherited;
+  site := DockMaster.GetAnchorSite(self);
+  if site.isNil then
+    exit;
+  newParent := site.Parent;
+  if fOldParent <> newParent then
+  begin
+    if fOldParent.isNil and newParent.isNotNil and assigned(fOnDockingChanged) then
+      fOnDockingChanged(self, wdsDocked)
+    else if fOldParent.isNotNil and newParent.isNil and assigned(fOnDockingChanged) then
+      fOnDockingChanged(self, wdsUndocked);
+  end;
+end;
+
 {$ENDREGION}
 
 {$REGION ICEContextualActions---------------------------------------------------}