added UnsetToolTip() which is also provided (as empty function) in wxUSE_TOOLTIPS==0 case unlike SetToolTip(NULL)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@55268 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/window.h

@@ -1208,16 +1208,20 @@ public:
 #if wxUSE_TOOLTIPS
         // the easiest way to set a tooltip for a window is to use this method
     void SetToolTip( const wxString &tip );
-        // attach a tooltip to the window
+        // attach a tooltip to the window, pointer can be NULL to remove
+        // existing tooltip
     void SetToolTip( wxToolTip *tip ) { DoSetToolTip(tip); }
+        // more readable synonym for SetToolTip(NULL)
+    void UnsetToolTip() { SetToolTip(NULL); }
         // get the associated tooltip or NULL if none
     wxToolTip* GetToolTip() const { return m_tooltip; }
     wxString GetToolTipText() const;
-#else
+#else // !wxUSE_TOOLTIPS
         // make it much easier to compile apps in an environment
         // that doesn't support tooltips, such as PocketPC
-    inline void SetToolTip( const wxString & WXUNUSED(tip) ) {}
+    void SetToolTip(const wxString & WXUNUSED(tip)) { }
-#endif // wxUSE_TOOLTIPS
+    void UnsetToolTip() { }
+#endif // wxUSE_TOOLTIPS/!wxUSE_TOOLTIPS
 
     // drag and drop
     // -------------

interface/wx/window.h

@@ -2399,8 +2399,16 @@ public:
     //@{
     /**
         Attach a tooltip to the window.
-        See also: GetToolTip(),
+
-         wxToolTip
+        wxToolTip pointer can be @NULL in the overload taking the pointer,
+        meaning to unset any existing tooltips, however UnsetToolTip() provides
+        a more readable alternative to this operation.
+
+        Notice that these methods are always available, even if wxWidgets was
+        compiled with @c wxUSE_TOOLTIPS set to 0, but don't do anything in this
+        case.
+
+        @see GetToolTip(), wxToolTip
     */
     void SetToolTip(const wxString& tip);
     void SetToolTip(wxToolTip* tip);
@@ -2584,6 +2592,15 @@ public:
     */
     static void UnreserveControlId(wxWindowID id, int count = 1);
 
+    /**
+        Unset any existing tooltip.
+
+        @since 2.9.0
+
+        @see SetToolTip()
+     */
+    void UnsetToolTip();
+
     /**
         Calling this method immediately repaints the invalidated area of the window and
         all of its children recursively while this would usually only happen when the