mq_tab_body_new(): Assign focus to Web view

This fixes the following assertion in GTK+ versions before 3.15.3:

    Gtk-CRITICAL **: gtk_widget_is_ancestor: assertion 'GTK_IS_WIDGET (widget)' failed

This assertion occurs when:

 1. No widget has been given input focus,
 2. A popover (e.g. the tab label context menu) is shown, and
 3. The window regains focus.

This is because of the following code in window_focus_in() in
gtk/gtkpopover.c (from 3.14.x):

          focus = gtk_window_get_focus (GTK_WINDOW (widget));

          if (!gtk_widget_is_ancestor (focus, GTK_WIDGET (popover)))
            gtk_widget_grab_focus (GTK_WIDGET (popover));

When no widget has focus, the first argument to gtk_widget_is_ancestor()
(which is checked with a GTK_IS_WIDGET() assertion) is NULL.

So, some widget needs to have focus before a popover is shown and the
window regains focus.

Arguably, this is a bug in GTK+, and it has been fixed in GTK+ 3.15.3:

    https://git.gnome.org/browse/gtk+/commit/gtk/gtkpopover.c?id=e26fddc

With that change, the above lines from window_focus_in() now read:

          focus = gtk_window_get_focus (GTK_WINDOW (widget));

          if (focus == NULL || !gtk_widget_is_ancestor (focus, GTK_WIDGET (popover)))
            gtk_widget_grab_focus (GTK_WIDGET (popover));

That is, if focus is NULL, don't check if popover is an ancestor of it.
Instead just give focus to popover.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/tab-body.c b/src/tab-body.c
index d195f6d..44c4451 100644
--- a/src/tab-body.c
+++ b/src/tab-body.c
@@ -38,6 +38,7 @@ mq_tab_body_new(gchar *uri)
 
 	body->container = GTK_WIDGET(body->web_view);
 	gtk_widget_set_vexpand(body->container, TRUE);
+	gtk_widget_grab_focus(body->container);
 
 	return body;
 }