Add wxRibbonButtonBar::GetItem(), GetItemById() and GetItemId().

Allow accessing the ribbon bar buttons either by index or ID.

See #14630.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72526 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/ribbon/buttonbar.h

@@ -377,6 +377,29 @@ public:
     */
     virtual size_t GetButtonCount() const;
 
+    /**
+        Returns the N-th button of the bar.
+
+        @see GetButtonCount()
+
+        @since 2.9.5
+    */
+    virtual wxRibbonButtonBarButtonBase *GetItem(size_t n) const;
+
+    /**
+        Returns the first button having a given id or NULL if none matches.
+
+        @since 2.9.5
+    */
+    virtual wxRibbonButtonBarButtonBase *GetItemById(int id) const;
+
+    /**
+        Returns the id of a button.
+
+        @since 2.9.5
+    */
+    virtual int GetItemId(wxRibbonButtonBarButtonBase *) const;
+
     /**
         Calculate button layouts and positions.