DnD of filenames: make Wayland behave as Windows and macOS

and also add more detailed documentation of platform-specific behaviors.

2 files changed, 16 insertions, 12 deletions

diff --git a/documentation/src/events.dox b/documentation/src/events.dox
index 26a3cda83..2dc1c7b25 100644
--- a/documentation/src/events.dox
+++ b/documentation/src/events.dox
@@ -268,16 +268,7 @@ selection indication. Most modern programs ignore this.
 
 FLTK supports drag and drop of text and files from any
 application on the desktop to an FLTK widget. Text is transferred
-using UTF-8 encoding. Files are received as a list of full path
-and file names, separated by newline.
-
-On some X11 platforms and with Wayland, files are received as a URL-encoded UTF-8 string,
-that is, non-ASCII bytes (and a few others such as space and %) are
-replaced by the 3 bytes "%XY" where XY are the byte's hexadecimal value.
-The \ref fl_decode_uri() function can be used to transform in-place
-the received string into a proper UTF-8 string. On these platforms,
-strings corresponding to dropped files are further prepended
-by <tt>file://</tt> (or other prefixes such as <tt>computer://</tt>).
+using UTF-8 encoding.
 
 See Fl::dnd() for drag and drop from an FLTK widget.
 
@@ -290,6 +281,20 @@ depends on the protocol used on each platform.
 \p FL_DND_* events cannot be used in widgets derived
 from Fl_Group or Fl_Window.
 
+\subsection events_fl_dnd_files Dropped filenames
+Files are received as a list of full path and file names.
+- On some X11 platforms, files are received as a URL-encoded UTF-8 string,
+that is, non-ASCII bytes (and a few others such as space and %) are
+replaced by the 3 bytes "%XY" where XY are the byte's hexadecimal value.
+The \ref fl_decode_uri() function can be used to transform in-place
+the received string into a proper UTF-8 string. On these platforms,
+strings corresponding to dropped files are further prepended
+by <tt>file://</tt> (or other prefixes such as <tt>computer://</tt>).
+- Other X11 situations put all dropped filenames in a single line, separated by
+spaces.
+- On non-X11 platforms, including Wayland, files dropped are received one
+pathname per line, with no  <tt>'\\n'</tt> after the last pathname.
+
 \subsection events_fl_dnd_enter FL_DND_ENTER
 
 The mouse has been moved to point at this widget. A widget that is
diff --git a/documentation/src/wayland.dox b/documentation/src/wayland.dox
index 3dfa4d733..0b6b9aca0 100644
--- a/documentation/src/wayland.dox
+++ b/documentation/src/wayland.dox
@@ -763,8 +763,7 @@ FLTK can copy or paste plain UTF-8 text or image data to/from the clipboard. Ima
 clipboard as \c image/bmp mime type. Images in \c image/bmp or \c image/png mime types from the
 clipboard can be pasted to FLTK apps.
 
-Files dropped are received one per line with URL-encoded UTF-8 names prepended by
-<tt>file://</tt> (see \ref events_dnd).
+Files dropped are received one pathname per line, with no '\n' after the last pathname.
 
 
 \section wayland-egl EGL as support for OpenGL