Add wxWindowPtr smart pointer.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74774 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/windowptr.h

@@ -0,0 +1,82 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        interface/wx/windowptr.h
+// Purpose:     wxWindowPtr<T> class documentation.
+// Author:      Vaclav Slavik
+// Created:     2013-09-02
+// Copyright:   (c) 2013 Vaclav Slavik <vslavik@fastmail.fm>
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+/**
+    A reference-counted smart pointer for holding wxWindow instances.
+
+    This specialization of wxSharedPtr<T> is useful for holding
+    wxWindow-derived objects. Unlike wxSharedPtr<T> or @c std::shared_ptr<>, it
+    doesn't use the delete operator to destroy the value when reference count
+    drops to zero, but calls wxWindow::Destroy() to safely destroy the window.
+
+    The template parameter T must be wxWindow or a class derived from it.
+
+    @library{wxcore}
+    @category{smartpointers}
+
+    @since 3.0
+
+    @see wxSharedPtr<T>
+*/
+template<typename T>
+class wxWindowPtr<T> : public wxSharedPtr<T>
+{
+public:
+    /// Default constructor.
+    wxWindowPtr();
+
+    /**
+        Constructor.
+
+        Creates shared pointer from the raw pointer @a ptr and takes ownership
+        of it.
+    */
+    explicit wxWindowPtr(T* ptr);
+
+    /**
+        Constructor.
+
+        Creates shared pointer from the raw pointer @a ptr and deleter @a d
+        and takes ownership of it.
+
+        @param ptr  The raw pointer.
+        @param d    Deleter - a functor that is called instead of delete to
+                    free the @a ptr raw pointer when its reference count drops to
+                    zero.
+
+    */
+    template<typename Deleter>
+    explicit wxWindowPtr(T* ptr, Deleter d);
+
+    /// Copy constructor.
+    wxWindowPtr(const wxWindowPtr<T>& tocopy);
+
+    /**
+        Assignment operator.
+
+        Releases any previously held pointer and creates a reference to @a ptr.
+    */
+    wxWindowPtr<T>& operator=(T* ptr);
+
+    /**
+        Assignment operator.
+
+        Releases any previously held pointer and creates a reference to the
+        same object as @a topcopy.
+    */
+    wxWindowPtr<T>& operator=(const wxWindowPtr<T>& tocopy);
+
+    /**
+        Reset pointer to @a ptr.
+
+        If the reference count of the previously owned pointer was 1 it will be deleted.
+    */
+    void reset(T* ptr = NULL);
+};
+