refactor wxGTK mnemonics conversion functions in a separate file to be able to reuse them from wxMenu too

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@49869 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/mnemonics.cpp

@@ -0,0 +1,189 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        src/gtk/mnemonics.cpp
+// Purpose:     implementation of GTK mnemonics conversion functions
+// Author:      Vadim Zeitlin
+// Created:     2007-11-12
+// RCS-ID:      $Id$
+// Copyright:   (c) 2007 Vadim Zeitlin <vadim@wxwindows.org>
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// for compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+    #pragma hdrstop
+#endif
+
+#include "wx/private/stattext.h"        // for wxMarkupEntities
+
+#include "wx/gtk/private/mnemonics.h"
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// internal helper: apply the operation indicated by flag
+// ----------------------------------------------------------------------------
+
+enum MnemonicsFlag
+{
+    MNEMONICS_REMOVE,
+    MNEMONICS_CONVERT,
+    MNEMONICS_CONVERT_MARKUP
+};
+
+static wxString GTKProcessMnemonics(const wxString& label, MnemonicsFlag flag)
+{
+    wxString labelGTK;
+    labelGTK.reserve(label.length());
+    for ( wxString::const_iterator i = label.begin(); i != label.end(); ++i )
+    {
+        wxChar ch = *i;
+
+        switch ( ch )
+        {
+            case wxT('&'):
+                if ( i + 1 == label.end() )
+                {
+                    // "&" at the end of string is an error
+                    wxLogDebug(wxT("Invalid label \"%s\"."), label);
+                    break;
+                }
+
+                if ( flag == MNEMONICS_CONVERT_MARKUP )
+                {
+                    bool isMnemonic = true;
+                    size_t distanceFromEnd = label.end() - i;
+
+                    // is this ampersand introducing a mnemonic or rather an entity?
+                    for (size_t j=0; j < wxMARKUP_ENTITY_MAX; j++)
+                    {
+                        const wxChar *entity = wxMarkupEntities[wxMARKUP_ELEMENT_NAME][j];
+                        size_t entityLen = wxStrlen(entity);
+
+                        if (distanceFromEnd >= entityLen &&
+                            wxString(i, i + entityLen) == entity)
+                        {
+                            labelGTK << entity;
+                            i += entityLen - 1;     // the -1 is because main for()
+                                                    // loop already increments i
+                            isMnemonic = false;
+
+                            break;
+                        }
+                    }
+
+                    if (!isMnemonic)
+                        continue;
+                }
+
+                ch = *(++i); // skip '&' itself
+                switch ( ch )
+                {
+                    case wxT('&'):
+                        // special case: "&&" is not a mnemonic at all but just
+                        // an escaped "&"
+                        if ( flag == MNEMONICS_CONVERT_MARKUP )
+                            labelGTK += wxT("&amp;");
+                        else
+                            labelGTK += wxT('&');
+                        break;
+
+                    case wxT('_'):
+                        if ( flag != MNEMONICS_REMOVE )
+                        {
+                            // '_' can't be a GTK mnemonic apparently so
+                            // replace it with something similar
+                            labelGTK += wxT("_-");
+                            break;
+                        }
+                        //else: fall through
+
+                    default:
+                        if ( flag != MNEMONICS_REMOVE )
+                            labelGTK += wxT('_');
+                        labelGTK += ch;
+                }
+                break;
+
+            case wxT('_'):
+                if ( flag != MNEMONICS_REMOVE )
+                {
+                    // escape any existing underlines in the string so that
+                    // they don't become mnemonics accidentally
+                    labelGTK += wxT("__");
+                    break;
+                }
+                //else: fall through
+
+            default:
+                labelGTK += ch;
+        }
+    }
+
+    return labelGTK;
+}
+
+// ----------------------------------------------------------------------------
+// public functions
+// ----------------------------------------------------------------------------
+
+wxString wxGTKRemoveMnemonics(const wxString& label)
+{
+    return GTKProcessMnemonics(label, MNEMONICS_REMOVE);
+}
+
+wxString wxConvertMnemonicsToGTK(const wxString& label)
+{
+    return GTKProcessMnemonics(label, MNEMONICS_CONVERT);
+}
+
+wxString wxConvertMnemonicsToGTKMarkup(const wxString& label)
+{
+    return GTKProcessMnemonics(label, MNEMONICS_CONVERT_MARKUP);
+}
+
+wxString wxConvertMnemonicsFromGTK(const wxString& gtkLabel)
+{
+    wxString label;
+    for ( const wxChar *pc = gtkLabel.c_str(); *pc; pc++ )
+    {
+        // '_' is the escape character for GTK+.
+
+        if ( *pc == wxT('_') && *(pc+1) == wxT('_'))
+        {
+            // An underscore was escaped.
+            label += wxT('_');
+            pc++;
+        }
+        else if ( *pc == wxT('_') )
+        {
+            // Convert GTK+ hotkey symbol to wxWidgets/Windows standard
+            label += wxT('&');
+        }
+        else if ( *pc == wxT('&') )
+        {
+            // Double the ampersand to escape it as far as wxWidgets is concerned
+            label += wxT("&&");
+        }
+        else
+        {
+            // don't remove ampersands '&' since if we have them in the menu title
+            // it means that they were doubled to indicate "&" instead of accelerator
+            label += *pc;
+        }
+    }
+
+    return label;
+}
+