richmemo: based on the patch by Andrey Korol (#30618), receiving ZoomFactor from widgetset (if hot keys were used to zoom the editor, w/o notifications to LCL). Win32 implementation added.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@5306 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/richmemo/richmemo.pas

@@ -593,6 +593,10 @@ end;
 function TCustomRichMemo.GetZoomFactor: Double;
 begin
   Result:=fZoomFactor;
+  if HandleAllocated then begin
+    if TWSCustomRichMemoClass(WidgetSetClass).GetZoomFactor(Self, Result) then
+      fZoomFactor:=Result;
+  end;
 end;
 
 procedure TCustomRichMemo.SetZoomFactor(AValue: Double);

components/richmemo/win32/win32richmemo.pas

@@ -127,6 +127,7 @@ type
       const SearchOpts: TIntSearchOpt; var ATextStart, ATextLength: Integer ): Boolean; override;
 
     class procedure SetZoomFactor(const AWinControl: TWinControl; AZoomFactor: Double); override;
+    class function GetZoomFactor(const AWinControl: TWinControl; var AZoomFactor: Double): Boolean; override;
 
     class function InlineInsert(const AWinControl: TWinControl; ATextStart, ATextLength: Integer;
       const ASize: TSize; AHandler: TRichMemoInline; var wsObj: TRichMemoInlineWSObject): Boolean; override;
@@ -1209,6 +1210,18 @@ begin
   SendMessage( AWinControl.Handle, EM_SETZOOM, round(AZoomFactor * DN), DN);
 end;
 
+class function TWin32WSCustomRichMemo.GetZoomFactor(const AWinControl: TWinControl; var AZoomFactor: Double): Boolean;
+var
+  numerator, denominator: Integer; // todo: Are they always integers? or can they be something else in 64-bit?
+begin
+  Result:=SendMessage(AWinControl.Handle, EM_GETZOOM, WParam(@numerator), LParam(@denominator))<>0;
+  if Result then begin
+    Result:=(numerator <> 0) and (denominator <> 0);
+    if Result then
+      AZoomFactor := double(numerator)/ double(denominator);
+  end;
+end;
+
 class function TWin32WSCustomRichMemo.InlineInsert(
   const AWinControl: TWinControl; ATextStart, ATextLength: Integer;
   const ASize: TSize; AHandler: TRichMemoInline;

components/richmemo/wsrichmemo.pas

@@ -106,6 +106,7 @@ type
     class function SearchEx(const AWinControl: TWinControl; const ANiddle: string; const SearchOpts: TIntSearchOpt; var TextStart, TextLength: Integer): Boolean; virtual;
 
     class procedure SetZoomFactor(const AWinControl: TWinControl; AZoomFactor: Double); virtual;
+    class function GetZoomFactor(const AWinControl: TWinControl; var AZoomFactor:Double): Boolean; virtual;
 
     //inline handler
     class function InlineInsert(const AWinControl: TWinControl; ATextStart, ATextLength: Integer;
@@ -379,6 +380,11 @@ begin
 
 end;
 
+class function TWSCustomRichMemo.GetZoomFactor(const AWinControl: TWinControl; var AZoomFactor: Double): Boolean;
+begin
+  Result:=false;
+end;
+
 class function TWSCustomRichMemo.InlineInsert(const AWinControl: TWinControl;
   ATextStart, ATextLength: Integer; const ASize: TSize; AHandler: TRichMemoInline;
   var wsObj: TRichMemoInlineWSObject): Boolean;