Allow constructing wxBitmapBundle from XPM data for compatibility

Add another compatibility implicit constructor to allow the existing
code, directly passing XPM data to various functions that used to take
wxBitmap or wxIcon and now taking wxBitmapBundle, to work.

Closes #22566.

include/wx/bmpbndl.h

@@ -45,6 +45,12 @@ public:
     // wxBitmapBundle.
     wxBitmapBundle(const wxImage& image);
 
+    // And another one from XPM data, as it's relatively common to pass it to
+    // various functions that take wxBitmapBundle in the existing code. It is
+    // not formally deprecated, but should be avoided in any new code and can
+    // become deprecated in the future.
+    wxBitmapBundle(const char* const* xpm);
+
     // Default copy ctor and assignment operator and dtor would be ok, but need
     // to be defined out of line, where wxBitmapBundleImpl is fully declared.
 

interface/wx/bmpbndl.h

@@ -126,6 +126,18 @@ public:
      */
     wxBitmapBundle(const wxImage& image);
 
+    /**
+        Conversion constructor from XPM data.
+
+        This constructor overload exists only for compatibility with the
+        existing code passing XPM data (e.g. @c foo_xpm after including @c
+        foo.xpm) directly to the functions expecting a bitmap. Don't use it in
+        the new code, as it is likely to be deprecated in the future.
+
+        @since 3.2.0
+     */
+    wxBitmapBundle(const char* const* xpm);
+
     /**
         Copy constructor creates a copy of another bundle.
      */

src/common/bmpbndl.cpp

@@ -358,6 +358,11 @@ wxBitmapBundle::wxBitmapBundle(const wxImage& image)
 {
 }
 
+wxBitmapBundle::wxBitmapBundle(const char* const* xpm)
+    : m_impl(new wxBitmapBundleImplSet(wxBitmap(xpm)))
+{
+}
+
 wxBitmapBundle::wxBitmapBundle(const wxBitmapBundle& other)
     : m_impl(other.m_impl)
 {