18.04gnome-shellindicator
App indicators of gnome are disappearing after lock screen. When I unlock the screen, indicators are not there anymore. If I restart gnome using ALT+F2+r, indicator appear again. To be clear, indicators are missing after logging in, obviously they are not shown in the lock screen as expected.
I've tried installing TopIcons plus extension and tried enabling/disabling Ubuntu appindicators extension, but no difference.
Well, it is really simpler then I expected. There is no specific API for it. Because it is just a GSimpleActionGroup & with corresponding GMenu's exported through DBus then Unity is told about their presence using declaration file with same name put in /usr/share/unity/indicators/. No need for any other library.
Here a very small C language example:
Get a copy of tests/indicator-test-service.c from libindicator source
apt-get source libindicator
cp libindicator-*/tests/indicator-test-service.c .
cp libindicator-*/tests/com.canonical.indicator.test* .
indicator-test-service.c no changes
#include <gio/gio.h>
typedef struct
{
GSimpleActionGroup *actions;
GMenu *menu;
guint actions_export_id;
guint menu_export_id;
} IndicatorTestService;
static void
bus_acquired (GDBusConnection *connection,
const gchar *name,
gpointer user_data)
{
IndicatorTestService *indicator = user_data;
GError *error = NULL;
indicator->actions_export_id = g_dbus_connection_export_action_group (connection,
"/com/canonical/indicator/test",
G_ACTION_GROUP (indicator->actions),
&error);
if (indicator->actions_export_id == 0)
{
g_warning ("cannot export action group: %s", error->message);
g_error_free (error);
return;
}
indicator->menu_export_id = g_dbus_connection_export_menu_model (connection,
"/com/canonical/indicator/test/desktop",
G_MENU_MODEL (indicator->menu),
&error);
if (indicator->menu_export_id == 0)
{
g_warning ("cannot export menu: %s", error->message);
g_error_free (error);
return;
}
}
static void
name_lost (GDBusConnection *connection,
const gchar *name,
gpointer user_data)
{
IndicatorTestService *indicator = user_data;
if (indicator->actions_export_id)
g_dbus_connection_unexport_action_group (connection, indicator->actions_export_id);
if (indicator->menu_export_id)
g_dbus_connection_unexport_menu_model (connection, indicator->menu_export_id);
}
static void
activate_show (GSimpleAction *action,
GVariant *parameter,
gpointer user_data)
{
g_message ("showing");
}
int
main (int argc, char **argv)
{
IndicatorTestService indicator = { 0 };
GMenuItem *item;
GMenu *submenu;
GActionEntry entries[] = {
{ "_header", NULL, NULL, "{'label': <'Test'>,"
" 'icon': <'indicator-test'>,"
" 'accessible-desc': <'Test indicator'> }", NULL },
{ "show", activate_show, NULL, NULL, NULL }
};
GMainLoop *loop;
indicator.actions = g_simple_action_group_new ();
g_simple_action_group_add_entries (indicator.actions, entries, G_N_ELEMENTS (entries), NULL);
submenu = g_menu_new ();
g_menu_append (submenu, "Show", "indicator.show");
item = g_menu_item_new (NULL, "indicator._header");
g_menu_item_set_attribute (item, "x-canonical-type", "s", "com.canonical.indicator.root");
g_menu_item_set_submenu (item, G_MENU_MODEL (submenu));
indicator.menu = g_menu_new ();
g_menu_append_item (indicator.menu, item);
g_bus_own_name (G_BUS_TYPE_SESSION,
"com.canonical.indicator.test",
G_BUS_NAME_OWNER_FLAGS_NONE,
bus_acquired,
NULL,
name_lost,
&indicator,
NULL);
loop = g_main_loop_new (NULL, FALSE);
g_main_loop_run (loop);
g_object_unref (submenu);
g_object_unref (item);
g_object_unref (indicator.actions);
g_object_unref (indicator.menu);
g_object_unref (loop);
return 0;
}
com.canonical.indicator.test modified to add lock & greeter mode
[Indicator Service]
Name=indicator-test
ObjectPath=/com/canonical/indicator/test
[desktop]
ObjectPath=/com/canonical/indicator/test/desktop
[desktop_greeter]
ObjectPath=/com/canonical/indicator/test/desktop
[desktop_lockscreen]
ObjectPath=/com/canonical/indicator/test/desktop
com.canonical.indicator.test.service remove .in postfix from filename and change the executable path
[D-BUS Service]
Name=com.canonical.indicator.test
Exec=/usr/lib/x86_64-linux-gnu/indicator-test/indicator-test-service
Compile it
gcc -o indicator-test-service indicator-test-service.c `pkg-config --cflags --libs gtk+-3.0`
Manual Installation
sudo su
mkdir /usr/lib/x86_64-linux-gnu/indicator-test/
cp indicator-test-service /usr/lib/x86_64-linux-gnu/indicator-test/
cp com.canonical.indicator.test /usr/share/unity/indicators/
cp com.canonical.indicator.test.service /usr/share/dbus-1/services/
Configuration for Greeter, override the default indicators list
90_unity-greeter.gschema.override
[com.canonical.unity-greeter]
indicators=['ug-accessibility', 'com.canonical.indicator.keyboard', 'com.canonical.indicator.session', 'com.canonical.indicator.datetime', 'com.canonical.indicator.power', 'com.canonical.indicator.sound', 'com.canonical.indicator.test', 'application']
Install
cp 90_unity-greeter.gschema.override /usr/share/glib-2.0/schemas/
glib-compile-schemas /usr/share/glib-2.0/schemas/
Test
sudo service lightdm restart
DBus service is troublesome, if you want user to be able to close application anytime. It is better to use autostart instead, like default indicators do.
I have uploaded ready files here:
https://github.com/sneetsher/mysystemindicator_minimum
and a modified copy here:
https://github.com/sneetsher/mysystemindicator
Where I have tried different menu for different mode. It could be installed and tested quickly.
This seems too simple and can be easily ported to any other language that have support for GIO Gnome lib (including DBus). As I'm looking for python, I may add it later.
This is not full standalone indicator as the one above, it is just a share lib plugin, similar to libappmenu.so & libprintersmenu.so (application menu & printer indicator). It could be shown only in regular user session & greeter (Not on lock screen).
I couldn't make it work in my current machine, but I did before. Here the steps, may be I'm missing something.
Using same source above of libindicator
test/libdummy-indicator-*.c are examples (simple & visible the ones show up on the panel)
Compile
./autogen.sh
make
Install
sudo cp tests/.libs/libdummy-indicator-visible.so /usr/lib/indicators3/7/libdummy.so
Configure to show in greeter screen
90_unity-greeter.gschema.override use same name without lib prefix and .so extension.
[com.canonical.unity-greeter]
indicators=['ug-accessibility', 'com.canonical.indicator.keyboard', 'com.canonical.indicator.session', 'com.canonical.indicator.datetime', 'com.canonical.indicator.power', 'com.canonical.indicator.sound', 'application', 'dummy']
Install
cp 90_unity-greeter.gschema.override /usr/share/glib-2.0/schemas/
glib-compile-schemas /usr/share/glib-2.0/schemas/
I've encountered the same problem. I tried to remove the indicator-application-service completely, and see, the problem went away! I guess coming from 16.04 leaves some Unity-related stuff on my machine that is not only obsolete but prevents the AppIndicator extension from properly working.
What to do:
sudo apt remove indicator-application
Best Answer
I have the same "fail", even the lock screen doesn't work (I can't change the option in settings, it looks like I cannot change none of this). Maybe it's for an update. The only way is like you said, restarting Gnome or even the Ubuntu Appindicator, but you need start (K)Status (but the next session you need to do the same, off (K)Status and activate Ubuntu Appindicator if u want work this).