@@ -491,7 +491,7 @@ class XDotParser(DotParser):

             # create a Node object nevertheless, so that any edges to/from it

             # don't get lost.

             # TODO: Extract the position from subgraph > graph > bb attribute.

-            node = elements.Node(id, 0.0, 0.0, 0.0, 0.0, [], None)

+            node = elements.Node(id, 0.0, 0.0, 0.0, 0.0, [], None, None)

             self.node_by_name[id] = node

             return

@@ -509,7 +509,7 @@ class XDotParser(DotParser):

             url = None

         else:

             url = url.decode('utf-8')

-        node = elements.Node(id, x, y, w, h, shapes, url)

+        node = elements.Node(id, x, y, w, h, shapes, url, attrs.get("tooltip"))

         self.node_by_name[id] = node

         if shapes:

             self.nodes.append(node)

@@ -529,7 +529,7 @@ class XDotParser(DotParser):

         if shapes:

             src = self.node_by_name[src_id]

             dst = self.node_by_name[dst_id]

-            self.edges.append(elements.Edge(src, dst, points, shapes))

+            self.edges.append(elements.Edge(src, dst, points, shapes, attrs.get("tooltip")))

     def parse(self):

         DotParser.parse(self)

@@ -17,7 +17,8 @@ import gi

 gi.require_version('Gtk', '3.0')

 gi.require_version('PangoCairo', '1.0')

-from gi.repository import Gdk

+from gi.repository import Gdk, Gtk

+from xdot.ui.elements import Jump

 class DragAction(object):

@@ -63,6 +64,12 @@ class DragAction(object):

 class NullAction(DragAction):

+    _tooltip_window = Gtk.Window(Gtk.WindowType.POPUP)

+    _tooltip_label = Gtk.Label(xalign=0, yalign=0)

+    _tooltip_item = None

+

+    _tooltip_window.add(_tooltip_label)

+    _tooltip_label.show()

     def on_motion_notify(self, event):

         if event.is_hint:

@@ -76,9 +83,27 @@ class NullAction(DragAction):

         if item is not None:

             dot_widget.get_window().set_cursor(Gdk.Cursor(Gdk.CursorType.HAND2))

             dot_widget.set_highlight(item.highlight)

+            if item is not NullAction._tooltip_item:

+                if isinstance(item, Jump) and item.item.tooltip is not None:

+                    NullAction._tooltip_label.set_markup(item.item.tooltip.decode())

+                    NullAction._tooltip_window.resize(

+                      NullAction._tooltip_label.get_preferred_width().natural_width,

+                      NullAction._tooltip_label.get_preferred_height().natural_height

+                    )

+                    NullAction._tooltip_window.show()

+                else:

+                    NullAction._tooltip_window.hide()

+                    NullAction._tooltip_label.set_markup("")

+                NullAction._tooltip_item = item

+            if NullAction._tooltip_window.is_visible:

+                pointer = NullAction._tooltip_window.get_screen().get_root_window().get_pointer()

+                NullAction._tooltip_window.move(pointer.x + 15, pointer.y + 10)

         else:

             dot_widget.get_window().set_cursor(None)

             dot_widget.set_highlight(None)

+            NullAction._tooltip_window.hide()

+            NullAction._tooltip_label.set_markup("")

+            NullAction._tooltip_item = None

 class PanAction(DragAction):

@@ -469,7 +469,7 @@ class Element(CompoundShape):

 class Node(Element):

-    def __init__(self, id, x, y, w, h, shapes, url):

+    def __init__(self, id, x, y, w, h, shapes, url, tooltip):

         Element.__init__(self, shapes)

         self.id = id

@@ -482,6 +482,7 @@ class Node(Element):

         self.y2 = y + 0.5*h

         self.url = url

+        self.tooltip = tooltip

     def is_inside(self, x, y):

         return self.x1 <= x and x <= self.x2 and self.y1 <= y and y <= self.y2

@@ -510,11 +511,12 @@ def square_distance(x1, y1, x2, y2):

 class Edge(Element):

-    def __init__(self, src, dst, points, shapes):

+    def __init__(self, src, dst, points, shapes, tooltip):

         Element.__init__(self, shapes)

         self.src = src

         self.dst = dst

         self.points = points

+        self.tooltip = tooltip

     RADIUS = 10