diff --git a/lcl/lcltaskdialog.pas b/lcl/lcltaskdialog.pas
index b5a0edec36..2d27c56629 100644
--- a/lcl/lcltaskdialog.pas
+++ b/lcl/lcltaskdialog.pas
@@ -799,6 +799,9 @@ var
 
 var
   ARadioOffset: integer;
+const
+  FirstButtonIndex = 100;
+  FirstRadioButtonIndex = 200;
 begin
   if (byte(aCommonButtons)=0) and (Buttons='') then begin
     aCommonButtons := [cbOk];
@@ -830,8 +833,8 @@ begin
     Config.pszMainInstruction := PWideChar(_WS(Inst));
     Config.pszContent := PWideChar(_WS(Content));
     RUCount := 0;
-    AddRU(Buttons,Config.cButtons,100);
-    AddRU(Radios,Config.cRadioButtons,200);
+    AddRU(Buttons,Config.cButtons,FirstButtonIndex);
+    AddRU(Radios,Config.cRadioButtons,FirstRadioButtonIndex);
     if Config.cButtons>0 then
       Config.pButtons := @But[0];
     if Config.cRadioButtons>0 then
@@ -857,7 +860,7 @@ begin
       works correctly if nDefaultRadioButton does NOT point to a radiobutton in the pRadioButtons array.
     }
     if not (tdfNoDefaultRadioButton in AFlags) then
-      Config.nDefaultRadioButton := aRadioDef+200;
+      Config.nDefaultRadioButton := aRadioDef+FirstRadioButtonIndex;
     Config.cxWidth := MulDiv(aWidth, 4, DialogBaseUnits);  // cxWidth needed in "dialog units"
     Config.pfCallback := @TaskDialogCallbackProc;
     Config.lpCallbackData := @self;
@@ -898,7 +901,7 @@ begin
     end else
       if aWidth<120 then aWidth := 120;
     Dialog.Form.ClientWidth := aWidth;
-    Dialog.Form.Height := 200;
+    Dialog.Form.Height := FirstRadioButtonIndex;
     Dialog.Form.Caption := Title;
     // create a white panel for the main dialog part
     Panel := TPanel.Create(Dialog.Form);
@@ -1005,7 +1008,7 @@ begin
               Hint := aHint; // note shown as Hint
             end;
             inc(Y,Height+2);
-            ModalResult := i+100;
+            ModalResult := i+FirstButtonIndex;
             OnClick := Dialog.Form.HandleEmulatedButtonClicked;
             if ModalResult=aButtonDef then
               Dialog.Form.ActiveControl := CommandLink;
@@ -1085,7 +1088,7 @@ begin
         try
           Text := SysUtils.trim(Buttons);
           for i := Count-1 downto 0 do
-            AddButton(Strings[i],i+100);
+            AddButton(Strings[i],i+FirstButtonIndex);
         finally
           Free;
         end;
@@ -1163,7 +1166,7 @@ begin
     RadioRes := 0;
     for i := 0 to high(Rad) do
       if Rad[i].Checked then
-        RadioRes := i+200;
+        RadioRes := i+FirstRadioButtonIndex;
   finally
     FreeAndNil(Dialog.Form);
   end;