Fix for issue #278: Can we use the qt/kde file picker instead of gtk?

Under the X11 platform, class Fl_Native_File_Chooser will behave as follows :
- if the KDE desktop is used and if command "kdialog" is available in the path,
the Qt/KDE file chooser is used;
- otherwise, if the GTK library is available at run-time,
the GTK file chooser is used;
- otherwise, the FLTK file chooser is used.

In addition, when Fl::OPTION_FNFC_USES_GTK is off, the FLTK file chooser
is always used.

1 files changed, 49 insertions, 0 deletions

diff --git a/src/Fl_Native_File_Chooser_Kdialog.H b/src/Fl_Native_File_Chooser_Kdialog.H
new file mode 100644
index 000000000..730b25e29
--- /dev/null
+++ b/src/Fl_Native_File_Chooser_Kdialog.H
@@ -0,0 +1,49 @@
+//
+// FLTK native file chooser widget : KDE version
+//
+// Copyright 2021 by Bill Spitzak and others.
+//
+// This library is free software. Distribution and use rights are outlined in
+// the file "COPYING" which should have been included with this file.  If this
+// file is missing or damaged, see the license at:
+//
+//     https://www.fltk.org/COPYING.php
+//
+// Please see the following page on how to report bugs and issues:
+//
+//     https://www.fltk.org/bugs.php
+//
+
+#ifndef FL_KDIALOG_NATIVE_FILE_CHOOSER_H
+#define FL_KDIALOG_NATIVE_FILE_CHOOSER_H 1
+
+#include <FL/Fl_Native_File_Chooser.H>
+
+class FL_EXPORT Fl_Kdialog_Native_File_Chooser_Driver : public Fl_Native_File_Chooser_FLTK_Driver {
+  friend class Fl_Native_File_Chooser;
+  char **_pathnames;
+  int _tpathnames;
+  char *_directory;
+  char *_preset_file;
+  char *_title;
+  static bool did_find_kdialog;
+  static bool have_looked_for_kdialog;
+  Fl_Kdialog_Native_File_Chooser_Driver(int val);
+  ~Fl_Kdialog_Native_File_Chooser_Driver();
+  int count() const;
+  const char *filename() const;
+  const char *filename(int i) const;
+  int show();
+  char *parse_filter(const char *f);
+  const char *filter() const;
+  virtual void filter(const char *f);
+  int filters() const;
+  void preset_file(const char *val);
+  const char *preset_file() const;
+  void directory(const char *val);
+  const char *directory() const;
+  void title(const char *val);
+  const char *title() const;
+};
+
+#endif // FL_KDIALOG_NATIVE_FILE_CHOOSER_H