Add wxMenuItem::IsCheck() and IsRadio() accessors.

The latter will be convenient to use in the upcoming changes to wxOSX radio
items management code and add the former for the symmetry.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74542 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/menuitem.h

@@ -268,8 +268,21 @@ public:
     */
     //@{
 
+    /**
+        Returns @true if the item is a check item.
+
+        Unlike IsCheckable() this doesn't return @true for the radio buttons.
+
+        @since 2.9.5
+     */
+    bool IsCheck() const;
+
     /**
         Returns @true if the item is checkable.
+
+        Notice that the radio buttons are considered to be checkable as well,
+        so this method returns @true for them too. Use IsCheck() if you want to
+        test for the check items only.
     */
     bool IsCheckable() const;
 
@@ -283,6 +296,13 @@ public:
     */
     virtual bool IsEnabled() const;
 
+    /**
+        Returns @true if the item is a radio button.
+
+        @since 2.9.5
+     */
+    bool IsRadio() const;
+
     /**
         Returns @true if the item is a separator.
     */