[Dextrose] [PATCH sugar v3] uy#698: Rectifying "Activity-icons not displaying, if notification-messages are shown"

[Ajay Garg]

---

Issue:
------
Originally discussed at :
http://lists.sugarlabs.org/archive/dextrose/2011-August/001340.html

and catched by Esteban Bordón, the issue is that whenever (and not just
at startup) any notification-messages are displayed, any Activity-icon
(and not just the Journal-Activity icon) is not displayed in the
top-panel-frame.

Technical history/details:
---------------------------

The mesh-, group-, home-, and activity-zoom buttons are a group of
radiobuttons; only one may be visibly-active at a time (this is
highlighted by the white-background of the corresponding selected
zoom-button).
Please see:
               "src/jarabe/frame/zoomtoolbar.py"
for code-details.

Similarly, all the opened activity-instances are shown by a yet another
group of radiobuttons; the selected activity being highlighed by the
corresponding selected activity-icon-button.

Now, what was happening, was that the notification-message-icon was
being added into the Activities-Tray (the second group of radiobuttons
as discussed above); but any further activity-icons were not being added
into the tray, because the notification-message-icon did not respect the
semantics of the activity-icons. Hence, the notification-message-icon, and
any other activity-icon (including Journal-activity icon) were not being
made a part of the same group.

Fix:
----

The top-panel-frame-setup (wherein the startup-notification-messages may
be added) gets processed, ONLY after the journal has been set-up.
Thus, "gio.File.monitor_file" has been used as the signalling mechanism.

As rightly pointed out by Bernie and Sascha, gio-file-monitor might not 
be the best signalling/synchronizing mechaism here. I tried to use threading.Event()
objects, but it needed to spawn another thread (note that all operations 
happen here in the context of the main-thread, even for "gobject.idle_add()" 
operations.


CHANGELOG:
---------

Changes of version-3 over version-2 :
-------------------------------------
a. Review changes as per Bernie and Sascha.


Changes of version-2 over version-1 :
-------------------------------------
a. Reverted to the previous-behaviour, wherein the notification-message-icon 
   is shown at the end of all activity-icons (Thanks Anish and Estaban). 
   Of course, this included the fix of the issue :)


 bin/sugar-session                  |   22 +++++++++++++++++++++-
 src/jarabe/frame/activitiestray.py |   18 ++++++++++++++++++
 2 files changed, 39 insertions(+), 1 deletions(-)

diff --git a/bin/sugar-session b/bin/sugar-session
index 40c9db7..1b28d4f 100755
--- a/bin/sugar-session
+++ b/bin/sugar-session
@@ -21,6 +21,7 @@ import sys
 import time
 import subprocess
 import shutil
+import gio
 
 if os.environ.get('SUGAR_LOGGER_LEVEL', '') == 'debug':
     print '%r STARTUP: Starting the shell' % time.time()
@@ -35,6 +36,9 @@ import gobject
 import dbus.glib
 import wnck
 
+MONITORS = []
+MONITOR_ACTION_TAKEN = False
+
 try:
     import xklavier
 except ImportError:
@@ -181,15 +185,31 @@ def setup_window_manager():
             shell=True):
         logging.warning('Can not disable metacity keybindings')
 
+def file_monitor_changed_cb(monitor, one_file, other_file, event_type):
+    global MONITOR_ACTION_TAKEN
+    if (not MONITOR_ACTION_TAKEN) and \
+       (one_file.get_path() == os.path.expanduser('~/.sugar/journal_created')):
+        if event_type == gio.FILE_MONITOR_EVENT_CREATED:
+            gobject.idle_add(setup_frame_cb)
+            MONITOR_ACTION_TAKEN = True
+
+def arrange_for_setup_frame_cb():
+    path = gio.File(os.path.expanduser('~/.sugar/journal_created'))
+    monitor = path.monitor_file()
+    monitor.connect('changed', file_monitor_changed_cb)
+    MONITORS.append(monitor)
+
 def bootstrap():
     setup_window_manager()
 
     from jarabe.view import launcher
     launcher.setup()
 
-    gobject.idle_add(setup_frame_cb)
     gobject.idle_add(setup_keyhandler_cb)
+
+    arrange_for_setup_frame_cb()
     gobject.idle_add(setup_journal_cb)
+
     gobject.idle_add(setup_notification_service_cb)
     gobject.idle_add(setup_file_transfer_cb)
     gobject.idle_add(show_software_updates_cb)
diff --git a/src/jarabe/frame/activitiestray.py b/src/jarabe/frame/activitiestray.py
index 2b8b7c6..1c8e285 100644
--- a/src/jarabe/frame/activitiestray.py
+++ b/src/jarabe/frame/activitiestray.py
@@ -246,6 +246,24 @@ class ActivitiesTray(HTray):
         button.connect('clicked', self.__activity_clicked_cb, home_activity)
         button.show()
 
+        # JournalActivity is always the first activity to be added.
+        # Broadcast the signal-of-its-creation.
+        if group is None:
+            self._signal_addition_of_journal_activity()
+
+    def _signal_addition_of_journal_activity(self):
+        monitor_file = os.path.expanduser('~/.sugar/journal_created')
+
+        # Remove the file, if it exists.
+        # This is important, since we are checking for the
+        # FILE_CREATED event in the monitor.
+        if os.path.exists(monitor_file):
+            os.remove(monitor_file)
+
+        # Now, create the file.
+        f = open(monitor_file, 'w')
+        f.close()
+
     def __activity_removed_cb(self, home_model, home_activity):
         logging.debug('__activity_removed_cb: %r', home_activity)
         button = self._buttons[home_activity]
-- 
1.7.4.4