Bring back dragging of elements from the activities to the frame clipboard - SL #3819

TestCase:

- open an activity like Browse, Read, Log (not Write, is a special case)
- bring up the frame
- drag things to the left side panel of the frame (images, links, or selected text)

The elements should be added to the clipboard which is inside the
panel.  They should have the proper icon and they should popup a
palette to act on them.

Note: if the dragged object is a link from Browse, Sugar tries to copy
the html to the disk.  But the current implementation looks wrong.  I
have opened #4477 to track it: http://bugs.sugarlabs.org/ticket/4477

Note: this doesn't solve the inverse operation: drag from the
clipboard to the activity.  This will be done in another patch.

API fixes:

- gtk.SelectionData.type  ->  Gtk.SelectionData.get_data_type().name() [1]
- gtk.SelectionData.data  ->  Gtk.SelectionData.get_data() [2]
- gtk.SelectionData.target  ->  Gtk.SelectionData.get_target() [3]
- context.targets  ->  context.list_targets() [4]
- context.drop_finish(...)  ->  Gdk.drop_finish(context, ...) [5]
- context.drag_status(...)  ->  Gdk.drag_status(context, ...) [6]
- context.get_source_widget()  ->  Gdk.drag_get_source_widget(context) [7]

[1] https://developer.gnome.org/gtk3/3.5/gtk3-Selections.html#gtk-selection-data-get-data-type
[2] https://developer.gnome.org/gtk3/3.5/gtk3-Selections.html#gtk-selection-data-get-data
[3] https://developer.gnome.org/gtk3/3.5/gtk3-Selections.html#gtk-selection-data-get-target
[4] https://developer.gnome.org/gdk/stable/gdk-Drag-and-Drop.html#gdk-drag-context-list-targets
[5] https://developer.gnome.org/gdk/stable/gdk-Drag-and-Drop.html#gdk-drop-finish
[6] https://developer.gnome.org/gdk/stable/gdk-Drag-and-Drop.html#gdk-drag-status
[7] https://developer.gnome.org/gtk3/stable/gtk3-Drag-and-Drop.html#gtk-drag-get-source-widget

The type of Gtk.SelectionData now comes as a Gdk.Atom instead of
string.  We use the name of the type to keep our code working.

The data for the type 'text/uri-list' comes with a character '\x00' at
the end now.  But using SelectionData.get_uris() returns a proper list
(thanks to Flavio Danesse for the recommendation).  So we can use that
list instead of doing selection.get_data().split('\n') or
sugar3.mime.split_uri_list (which could be obsolete now).  In fact,
this change was made a while ago in clipboardpanelwindow.py, but not
in clipboardtray.py.  See commit f0d194f3 .

Signed-off-by: Manuel Quiñones <manuq@laptop.org>
Signed-off-by: Ajay Garg <ajay@activitycentral.com>

4 files changed, 27 insertions, 21 deletions

diff --git a/src/jarabe/frame/clipboardmenu.py b/src/jarabe/frame/clipboardmenu.py
index e6766fb..eef3861 100644
--- a/src/jarabe/frame/clipboardmenu.py
+++ b/src/jarabe/frame/clipboardmenu.py
@@ -195,7 +195,7 @@ class ClipboardMenu(Palette):
 
         transfer_ownership = False
         if most_significant_mime_type == 'text/uri-list':
-            uris = mime.split_uri_list(format_.get_data())
+            uris = format_.get_uris()
             if len(uris) == 1 and uris[0].startswith('file://'):
                 parsed_url = urlparse.urlparse(uris[0])
                 file_path = parsed_url.path  # pylint: disable=E1101
@@ -207,7 +207,7 @@ class ClipboardMenu(Palette):
                 mime_type = 'text/uri-list'
         else:
             if format_.is_on_disk():
-                parsed_url = urlparse.urlparse(format_.get_data())
+                parsed_url = urlparse.urlparse(format_.get_uris()[0])
                 file_path = parsed_url.path  # pylint: disable=E1101
                 transfer_ownership = False
                 mime_type = mime.get_for_file(file_path)
diff --git a/src/jarabe/frame/clipboardobject.py b/src/jarabe/frame/clipboardobject.py
index e79fa46..5a3c9fe 100644
--- a/src/jarabe/frame/clipboardobject.py
+++ b/src/jarabe/frame/clipboardobject.py
@@ -103,8 +103,8 @@ class ClipboardObject(object):
 
         format_ = mime.choose_most_significant(self._formats.keys())
         if format_ == 'text/uri-list':
-            data = self._formats['text/uri-list'].get_data()
-            uri = urlparse.urlparse(mime.split_uri_list(data)[0], 'file')
+            uris = self._formats[format_].get_uris()
+            uri = urlparse.urlparse(uris[0], 'file')
             scheme = uri.scheme  # pylint: disable=E1101
             if scheme == 'file':
                 path = uri.path  # pylint: disable=E1101
diff --git a/src/jarabe/frame/clipboardpanelwindow.py b/src/jarabe/frame/clipboardpanelwindow.py
index cfbc5f7..d67f27f 100644
--- a/src/jarabe/frame/clipboardpanelwindow.py
+++ b/src/jarabe/frame/clipboardpanelwindow.py
@@ -79,7 +79,7 @@ class ClipboardPanelWindow(FrameWindow):
                 cb_selections.append(selection)
 
         if target_is_uri:
-            uri = selection.get_data()
+            uri = selection.get_uris()[0]
             filename = uri[len('file://'):].strip()
             md5 = self._md5_for_file(filename)
             data_hash = hash(md5)
diff --git a/src/jarabe/frame/clipboardtray.py b/src/jarabe/frame/clipboardtray.py
index abc885e..c2735c5 100644
--- a/src/jarabe/frame/clipboardtray.py
+++ b/src/jarabe/frame/clipboardtray.py
@@ -76,26 +76,31 @@ class ClipboardTray(tray.VTray):
         return False
 
     def _add_selection(self, object_id, selection):
-        if not selection.data:
+        if not selection.get_data():
             return
 
-        logging.debug('ClipboardTray: adding type %r', selection.type)
+        selection_data = selection.get_data()
+
+        selection_type_atom = selection.get_data_type()
+        selection_type = selection_type_atom.name()
+
+        logging.debug('ClipboardTray: adding type %r', selection_type)
 
         cb_service = clipboard.get_instance()
-        if selection.type == 'text/uri-list':
-            uris = selection.data.split('\n')
+        if selection_type == 'text/uri-list':
+            uris = selection.get_uris()
             if len(uris) > 1:
                 raise NotImplementedError('Multiple uris in text/uri-list' \
                                           ' still not supported.')
 
             cb_service.add_object_format(object_id,
-                                         selection.type,
+                                         selection_type,
                                          uris[0],
                                          on_disk=True)
         else:
             cb_service.add_object_format(object_id,
-                                         selection.type,
-                                         selection.data,
+                                         selection_type,
+                                         selection_data,
                                          on_disk=False)
 
     def _object_added_cb(self, cb_service, cb_object):
@@ -132,9 +137,9 @@ class ClipboardTray(tray.VTray):
         logging.debug('ClipboardTray._drag_motion_cb')
 
         if self._internal_drag(context):
-            context.drag_status(Gdk.DragAction.MOVE, time)
+            Gdk.drag_status(context, Gdk.DragAction.MOVE, time)
         else:
-            context.drag_status(Gdk.DragAction.COPY, time)
+            Gdk.drag_status(context, Gdk.DragAction.COPY, time)
             self.props.drag_active = True
 
         return True
@@ -148,15 +153,16 @@ class ClipboardTray(tray.VTray):
         if self._internal_drag(context):
             # TODO: We should move the object within the clipboard here
             if not self._context_map.has_context(context):
-                context.drop_finish(False, Gtk.get_current_event_time())
+                Gdk.drop_finish(context, False, Gtk.get_current_event_time())
             return False
 
         cb_service = clipboard.get_instance()
         object_id = cb_service.add_object(name="")
 
-        self._context_map.add_context(context, object_id, len(context.targets))
+        context_targets = context.list_targets()
+        self._context_map.add_context(context, object_id, len(context_targets))
 
-        for target in context.targets:
+        for target in context_targets:
             if str(target) not in ('TIMESTAMP', 'TARGETS', 'MULTIPLE'):
                 widget.drag_get_data(context, target, time)
 
@@ -167,13 +173,13 @@ class ClipboardTray(tray.VTray):
     def drag_data_received_cb(self, widget, context, x, y, selection,
                               targetType, time):
         logging.debug('ClipboardTray: got data for target %r',
-            selection.target)
+            selection.get_target())
 
         object_id = self._context_map.get_object_id(context)
         try:
             if selection is None:
                 logging.warn('ClipboardTray: empty selection for target %s',
-                    selection.target)
+                    selection.get_target())
             else:
                 self._add_selection(object_id, selection)
 
@@ -181,10 +187,10 @@ class ClipboardTray(tray.VTray):
             # If it's the last target to be processed, finish
             # the dnd transaction
             if not self._context_map.has_context(context):
-                context.drop_finish(True, Gtk.get_current_event_time())
+                Gdk.drop_finish(context, True, Gtk.get_current_event_time())
 
     def _internal_drag(self, context):
-        source_widget = context.get_source_widget()
+        source_widget = Gtk.drag_get_source_widget(context)
         if source_widget is None:
             return False
         view_ancestor = source_widget.get_ancestor(Gtk.Viewport)