Apply partial workaround for GTK3 tooltip positioning bug (MAGEIA#30574)

GTK3 has multiple tooltip positioning issues.
We can only partially dodge this.

Apply a hack from:
* https://bugs.mageia.org/show_bug.cgi?id=30574
* http://sophie.zarb.org/rpms/9d697fa6536295e90f166ca7199d7850/files/11

Thanks to Nicolas Salguero for the investigations.

To reduce the edit surface in the code of plugins, I moved the duplicated
parts to a separate function in misc.c and make it a part of lxpanel API.
(Ugly!)

Known issues:

1. The pager plugin tooltips are still buggy.
2. With this hack, tooltips don't seem to always show up when they should.

Partially fixes issue lxde#41

ChangeLog

@@ -4,6 +4,7 @@
 * Fix SF#773: Pager applet breaks panel layout with GTK3.
 * Fix issue: LXPanel and/or the task bar plugin grows in width above the
     configured size with GTK3.
+* Apply partial workaround for GTK3 tooltip positioning bug. (MAGEIA#30574)
 * Calculate _NET_WM_STRUT_PARTIAL with respect of HiDPI scale factor when built
     with GTK3.
 * batt: Fix division by zero with broken batteries. (SF#908)

plugins/batt/batt.c

@@ -564,6 +564,8 @@ static GtkWidget * constructor(LXPanel *panel, config_setting_t *settings)
     /* Start the update loop */
     lx_b->timer = g_timeout_add_seconds( 9, (GSourceFunc) update_timout, (gpointer) lx_b);
 
+    lxpanel_apply_hack_for_issue_41(lx_b->drawingArea);
+
     RET(p);
 }
 

plugins/launch-button.c

@@ -179,6 +179,9 @@ LaunchButton *launch_button_new(LXPanel *panel, GtkWidget *plugin, FmPath *id,
             return NULL;
         }
     }
+
+    lxpanel_apply_hack_for_issue_41(GTK_WIDGET(self));
+
     return self;
 }
 

plugins/monitors/monitors.c

@@ -285,6 +285,9 @@ cpu_tooltip_update (Monitor *m)
         tooltip_text = g_strdup_printf(_("CPU usage: %.2f%%"),
                 m->stats[ring_pos] * 100);
         gtk_widget_set_tooltip_text(m->da, tooltip_text);
+
+        lxpanel_apply_hack_for_issue_41(m->da);
+
         g_free(tooltip_text);
     }
 }
@@ -387,6 +390,9 @@ mem_tooltip_update (Monitor *m)
                 m->stats[ring_pos] * m->total / 1024,
                 m->stats[ring_pos] * 100);
         gtk_widget_set_tooltip_text(m->da, tooltip_text);
+
+        lxpanel_apply_hack_for_issue_41(m->da);
+
         g_free(tooltip_text);
     }
 }

plugins/netstat/statusicon.c

@@ -48,6 +48,8 @@ struct statusicon *create_statusicon(LXPanel *panel, GtkWidget *box,
     /* tooltip */
     gtk_widget_set_tooltip_text(newicon->main, tooltips);
 
+    lxpanel_apply_hack_for_issue_41(newicon->main);
+
     return newicon;
 }
 

plugins/task-button.c

@@ -102,6 +102,10 @@ struct _TaskButton
     unsigned int same_name :1;  /* TRUE if all visible windows have the same name */
     unsigned int entered_state :1; /* TRUE if cursor is inside taskbar button */
     unsigned int has_flash :1;  /* used by task_button_set_flash_state() */
+#if GTK_CHECK_VERSION(3, 0, 0)
+    GMutex idle_query_tp_mutex; /* mutex for callback reenabling query-tooltip */
+    guint idle_query_tooltip;   /* id of callback reenabling query-tooltip */
+#endif
 };
 
 enum {
@@ -1131,6 +1135,38 @@ static void task_update_icon(TaskButton *task, TaskDetails *details, Atom source
                                                          task, NULL);
 }
 
+#if GTK_CHECK_VERSION(3, 0, 0)
+static gboolean enable_query_tooltip(gpointer p_data)
+{
+    TaskButton *task = p_data;
+    if (g_mutex_trylock(&task->idle_query_tp_mutex))
+    {
+        if (!g_source_is_destroyed(g_main_current_source()))
+        {
+            GtkWidget *widget = p_data;
+            task->idle_query_tooltip = 0;
+            gtk_widget_set_has_tooltip(widget, TRUE);
+        }
+        g_mutex_unlock(&task->idle_query_tp_mutex);
+    }
+    return G_SOURCE_REMOVE;
+}
+
+static gboolean task_query_tooltip(GtkWidget *widget, gint x, gint y, gboolean keyboard_tip, GtkTooltip *tooltip, gpointer p_data)
+{
+    TaskButton *task = widget;
+    if (g_mutex_trylock(&task->idle_query_tp_mutex))
+    {
+        gtk_widget_set_has_tooltip(widget, FALSE);
+        GtkWidget *parent = gtk_widget_get_toplevel(widget);
+        gtk_widget_set_tooltip_text(parent, gtk_widget_get_tooltip_text(widget));
+        task->idle_query_tooltip = g_timeout_add(2 * G_TIME_SPAN_MILLISECOND, enable_query_tooltip, widget);
+        g_mutex_unlock(&task->idle_query_tp_mutex);
+    }
+    return TRUE;
+}
+#endif
+
 /* Draw the label and tooltip on a taskbar button. */
 static void task_draw_label(TaskButton *tb, gboolean bold_style, gboolean force)
 {
@@ -1228,6 +1264,12 @@ static void task_button_finalize(GObject *object)
 {
     TaskButton *self = (TaskButton *)object;
 
+#if GTK_CHECK_VERSION(3, 0, 0)
+    if (self->idle_query_tooltip)
+        g_source_remove(self->idle_query_tooltip);
+    g_mutex_clear(&self->idle_query_tp_mutex);
+#endif
+
     /* free all data */
     g_free(self->res_class);
     if (self->menu_list)
@@ -1368,6 +1410,18 @@ static gboolean task_button_leave_notify_event(GtkWidget *widget, GdkEventCrossi
 {
     TaskButton *tb = PANEL_TASK_BUTTON(widget);
 
+#if GTK_CHECK_VERSION(3, 0, 0)
+    if (g_mutex_trylock(&tb->idle_query_tp_mutex))
+    {
+        if (tb->idle_query_tooltip)
+        {
+            GtkWidget *parent = gtk_widget_get_toplevel(widget);
+            gtk_widget_set_has_tooltip(parent, FALSE);
+        }
+        g_mutex_unlock(&tb->idle_query_tp_mutex);
+    }
+#endif
+
     tb->entered_state = FALSE;
     task_draw_label(tb, FALSE, FALSE);
     if (tb->flags.flat_button)
@@ -1495,6 +1549,10 @@ TaskButton *task_button_new(Window win, gint desk, gint desks, LXPanel *panel,
     assemble_gui(self);
     /* and finally set visibility on it */
     gtk_widget_set_visible(GTK_WIDGET(self), self->n_visible > 0);
+#if GTK_CHECK_VERSION(3, 0, 0)
+    g_mutex_init(&self->idle_query_tp_mutex);
+    g_signal_connect(GTK_WIDGET(self), "query-tooltip", G_CALLBACK(task_query_tooltip), NULL);
+#endif
     return self;
 }
 

plugins/weather/weatherwidget.c

@@ -530,6 +530,8 @@ gtk_weather_render(GtkWeather * weather)
 
   gtk_widget_set_tooltip_text(GTK_WIDGET(weather), tooltip_text);
 
+  lxpanel_apply_hack_for_issue_41(weather);
+
   g_free(tooltip_text);
 }
 

src/misc.c

@@ -1258,6 +1258,12 @@ static gboolean fb_button_enter(GtkImage * widget, GdkEventCrossing * event)
 /* Handler for "leave-notify-event" signal on image that has highlighting requested. */
 static gboolean fb_button_leave(GtkImage * widget, GdkEventCrossing * event, gpointer user_data)
 {
+#if GTK_CHECK_VERSION(3, 0, 0)
+    /* XXX: a part of workaround for https://github.com/lxde/lxpanel/issues/41 */
+    GtkWidget *parent = gtk_widget_get_toplevel(GTK_WIDGET(widget));
+    gtk_widget_set_has_tooltip(parent, FALSE);
+#endif
+
     if (gtk_image_get_storage_type(widget) == GTK_IMAGE_PIXBUF)
     {
         ImgData * data = (ImgData *) g_object_get_qdata(G_OBJECT(widget), img_data_id);
@@ -1651,4 +1657,38 @@ gboolean lxpanel_launch_app(const char* exec, GList* files, gboolean in_terminal
     return (error == NULL);
 }
 
+/* XXX: workaround for https://github.com/lxde/lxpanel/issues/41 */
+/*
+    Tooltip positioning bug in GTK3.
+    * https://bugs.mageia.org/show_bug.cgi?id=30574
+    * https://github.com/lxde/lxpanel/issues/41
+*/
+
+#if GTK_CHECK_VERSION(3, 0, 0)
+static gboolean enable_query_tooltip(gpointer p_data)
+{
+    GtkWidget *widget = p_data;
+    gtk_widget_set_has_tooltip(widget, TRUE);
+    return G_SOURCE_REMOVE;
+}
+
+static gboolean plugin_query_tooltip(GtkWidget *widget, gint x, gint y, gboolean keyboard_tip, GtkTooltip *tooltip, gpointer p_data)
+{
+    gtk_widget_set_has_tooltip(widget, FALSE);
+    GtkWidget *parent = gtk_widget_get_toplevel(widget);
+    gtk_widget_set_tooltip_text(parent, gtk_widget_get_tooltip_text(widget));
+    g_timeout_add(2 * G_TIME_SPAN_MILLISECOND, enable_query_tooltip, widget);
+    return TRUE;
+}
+#endif
+
+void lxpanel_apply_hack_for_issue_41(GtkWidget *widget)
+{
+#if GTK_CHECK_VERSION(3, 0, 0)
+    g_signal_connect(widget, "query-tooltip", G_CALLBACK(plugin_query_tooltip), NULL);
+#else
+    (void) widget;
+#endif
+}
+
 /* vim: set sw=4 et sts=4 : */

src/misc.h

@@ -269,6 +269,8 @@ extern GtkWidget *lxpanel_image_new_for_fm_icon(LXPanel *panel, FmIcon *icon,
 extern gboolean lxpanel_image_change_icon(GtkWidget *img, const gchar *name,
                                           const char *fallback);
 
+extern void lxpanel_apply_hack_for_issue_41(GtkWidget *widget);
+
 G_END_DECLS
 
 #endif

src/panel.c

@@ -401,6 +401,15 @@ static gboolean lxpanel_button_press(GtkWidget *widget, GdkEventButton *event)
     return FALSE;
 }
 
+#if GTK_CHECK_VERSION(3, 0, 0)
+/* XXX: a part of workaround for https://github.com/lxde/lxpanel/issues/41 */
+static gboolean lxpanel_enter_notify(GtkWidget* widget, GdkEventCrossing event, gpointer p_data)
+{
+    gtk_widget_set_has_tooltip(widget, FALSE);
+    return FALSE;
+}
+#endif
+
 static void lxpanel_class_init(PanelToplevelClass *klass)
 {
     GObjectClass *gobject_class = (GObjectClass *)klass;
@@ -430,6 +439,7 @@ static void lxpanel_class_init(PanelToplevelClass *klass)
     widget_class->button_press_event = lxpanel_button_press;
     widget_class->button_release_event = _lxpanel_button_release;
     widget_class->motion_notify_event = _lxpanel_motion_notify;
+    widget_class->enter_notify_event = lxpanel_enter_notify;
 
     signals[ICON_SIZE_CHANGED] =
         g_signal_new("icon-size-changed",

src/plugin.c

@@ -587,6 +587,9 @@ GtkWidget *lxpanel_add_plugin(LXPanel *p, const char *name, config_setting_t *cf
     g_object_set_qdata(G_OBJECT(widget), lxpanel_plugin_qinit, (gpointer)init);
     g_object_set_qdata_full(G_OBJECT(widget), lxpanel_plugin_qsize,
                             g_new0(GdkRectangle, 1), g_free);
+
+    lxpanel_apply_hack_for_issue_41(widget);
+
     return widget;
 }