form: added OnCreate and OnDestroy

src/base/fresnel.forms.pas

@@ -45,6 +45,8 @@ type
     FFormStyle: TFormStyle;
     fMouseDownElement: TFresnelElement;
     fMouseUpElement : TFresnelElement;
+    FOnCreate: TNotifyEvent;
+    FOnDestroy: TNotifyEvent;
     FVisible: boolean;
     FWSForm: TFresnelWSForm;
     function GetCaption: TFresnelCaption;
@@ -61,6 +63,8 @@ type
     procedure SetFormWidth(const AValue: TFresnelLength);
     procedure SetVisible(const AValue: boolean);
   protected
+    procedure DoCreate; virtual;
+    procedure DoDestroy; virtual;
     procedure Loaded; override;
     procedure Notification(AComponent: TComponent; Operation: TOperation);
       override;
@@ -76,6 +80,8 @@ type
     constructor Create(AOwner: TComponent); override;
     constructor CreateNew(AOwner: TComponent); virtual;
     destructor Destroy; override;
+    procedure AfterConstruction; override;
+    procedure BeforeDestruction; override;
     procedure DomChanged; override;
     procedure Hide; virtual;
     procedure Show; virtual;
@@ -102,6 +108,8 @@ type
     property FormWidth: TFresnelLength read GetFormWidth write SetFormWidth;
     property FormHeight: TFresnelLength read GetFormHeight write SetFormHeight;
     property Visible: boolean read FVisible write SetVisible default True;
+    property OnCreate: TNotifyEvent read FOnCreate write FOnCreate;
+    property OnDestroy: TNotifyEvent read FOnDestroy write FOnDestroy;
   end;
   TFresnelCustomFormClass = Class of TFresnelCustomForm;
 
@@ -115,6 +123,8 @@ type
     property FormWidth;
     property FormHeight;
     property Stylesheet;
+    property OnCreate;
+    property OnDestroy;
   end;
   TFresnelFormClass = class of TFresnelForm;
 
@@ -405,6 +415,18 @@ begin
     Hide;
 end;
 
+procedure TFresnelCustomForm.DoCreate;
+begin
+  if Assigned(OnCreate) then
+    OnCreate(Self);
+end;
+
+procedure TFresnelCustomForm.DoDestroy;
+begin
+  if Assigned(OnDestroy) then
+    OnDestroy(Self);
+end;
+
 procedure TFresnelCustomForm.Loaded;
 begin
   FLLog(etDebug,['TFresnelCustomForm.Loaded ',ToString]);
@@ -505,6 +527,18 @@ begin
   inherited Destroy;
 end;
 
+procedure TFresnelCustomForm.AfterConstruction;
+begin
+  DoCreate;
+  inherited AfterConstruction;
+end;
+
+procedure TFresnelCustomForm.BeforeDestruction;
+begin
+  inherited BeforeDestruction;
+  DoDestroy;
+end;
+
 procedure TFresnelCustomForm.DomChanged;
 begin
   LayoutQueued:=true;