LCL: added TControl.ParentVisibleChanged

git-svn-id: trunk@46184 -

lcl/controls.pp

@@ -1362,6 +1362,7 @@ type
     function DoMouseWheelUp(Shift: TShiftState; MousePos: TPoint): Boolean; virtual;
     procedure VisibleChanging; virtual;
     procedure VisibleChanged; virtual;
+    procedure ParentVisibleChanged(aParent: TWinControl); virtual;
     procedure EnabledChanging; virtual;
     procedure EnabledChanged; virtual;
     procedure AddHandler(HandlerType: TControlHandlerType;
@@ -1914,6 +1915,7 @@ type
     procedure Remove(AControl: TControl);
     procedure AlignNonAlignedControls(ListOfControls: TFPList;
                                       var BoundsModified: Boolean);
+    procedure PropagateParentVisibleChanged(aParent: TWinControl);
   protected
     FWinControlFlags: TWinControlFlags;
     class procedure WSRegisterClass; override;
@@ -2074,6 +2076,7 @@ type
     procedure ShowControl(AControl: TControl); virtual;
     procedure UpdateControlState;
     procedure UpdateShowing; virtual; // checks control's handle visibility, called by DoAllAutoSize and UpdateControlState
+    procedure ParentVisibleChanged(aParent: TWinControl); override;
     procedure WndProc(var Message: TLMessage); override;
     procedure WSSetText(const AText: String); virtual;
   protected

lcl/include/control.inc

@@ -1805,6 +1805,15 @@ begin
   DoCallNotifyHandler(chtOnVisibleChanged);
 end;
 
+procedure TControl.ParentVisibleChanged(aParent: TWinControl);
+// called when a Parent (or grand parent) Visible property changed
+// and all parents in between have Visible=true
+// In other words: called when this control visibility changed due to
+//                 visibility change of Parent.
+begin
+
+end;
+
 {------------------------------------------------------------------------------
   procedure TControl.EnabledChanging;
 ------------------------------------------------------------------------------}
@@ -4270,7 +4279,7 @@ begin
         AdjustSize;
         if (not Visible) and Assigned(Parent) then
         begin
-          // control became invisible, so AdjustSize was not propagated
+          // control became invisible, so AdjustSize was not propagated to Parent
           // => propagate now
           Parent.InvalidatePreferredSize;
           Parent.AdjustSize;

lcl/include/wincontrol.inc

@@ -4340,6 +4340,12 @@ begin
   ChangeShowing(bShow);
 end;
 
+procedure TWinControl.ParentVisibleChanged(aParent: TWinControl);
+begin
+  inherited ParentVisibleChanged(aParent);
+  PropagateParentVisibleChanged(aParent);
+end;
+
 procedure TWinControl.Update;
 begin
   if HandleAllocated then UpdateWindow(Handle);
@@ -6136,6 +6142,22 @@ begin
   end;
 end;
 
+procedure TWinControl.PropagateParentVisibleChanged(aParent: TWinControl);
+var
+  i: Integer;
+  aControl: TControl;
+begin
+  for i:=0 to ControlCount-1 do
+  begin
+    aControl:=Controls[i];
+    if not aControl.Visible then
+      continue;
+    ParentVisibleChanged(aParent);
+    if aControl is TWinControl then
+      TWinControl(aControl).PropagateParentVisibleChanged(aParent);
+  end;
+end;
+
 class procedure TWinControl.WSRegisterClass;
 begin
   inherited WSRegisterClass;

lcl/lmessages.pp

@@ -224,7 +224,7 @@ const
   LM_CLEAR             = $0303;
 
 const
-  // Moved from Controls to avoid circles
+  // Moved from Controls to avoid circular dependencies
   CM_BASE                 = $B000;
   CM_LCLOFFSET            = $100;
   CM_ACTIVATE             = CM_BASE + 0;