[meld] meld.ui.notebook: Move tab movement handling to MeldNotebook class

[Kai Willadsen <kaiw src gnome org>]

commit 675d2333d4cc662c1a13888a7e4760d72fc0484d
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Wed Nov 4 07:50:24 2015 +1000

    meld.ui.notebook: Move tab movement handling to MeldNotebook class

 data/ui/meldapp-ui.xml |    7 ----
 data/ui/meldapp.ui     |    2 +-
 meld/meldwindow.py     |   39 -------------------------
 meld/ui/notebook.py    |   75 ++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 76 insertions(+), 47 deletions(-)
---
diff --git a/data/ui/meldapp-ui.xml b/data/ui/meldapp-ui.xml
index 330ecb3..d475f76 100644
--- a/data/ui/meldapp-ui.xml
+++ b/data/ui/meldapp-ui.xml
@@ -51,13 +51,6 @@
       <menuitem action="Stop" />
       <menuitem action="Refresh" />
     </menu>
-    <menu action="TabMenu">
-      <menuitem action="PrevTab" />
-      <menuitem action="NextTab" />
-      <separator/>
-      <menuitem action="MoveTabPrev" />
-      <menuitem action="MoveTabNext" />
-    </menu>
   </menubar>
 
   <toolbar action="Toolbar">
diff --git a/data/ui/meldapp.ui b/data/ui/meldapp.ui
index 4ac2c93..932aef7 100644
--- a/data/ui/meldapp.ui
+++ b/data/ui/meldapp.ui
@@ -28,7 +28,7 @@
             <property name="visible">True</property>
             <property name="can_focus">True</property>
             <property name="scrollable">True</property>
-            <property name="enable_popup">True</property>
+            <property name="enable_popup">False</property>
             <signal name="page-reordered" handler="after_page_reordered" after="yes" swapped="no"/>
             <signal name="switch-page" handler="on_switch_page" swapped="no"/>
             <signal name="switch-page" handler="after_switch_page" after="yes" swapped="no"/>
diff --git a/meld/meldwindow.py b/meld/meldwindow.py
index efbdac3..d3c5ad5 100644
--- a/meld/meldwindow.py
+++ b/meld/meldwindow.py
@@ -108,22 +108,6 @@ class MeldWindow(gnomeglade.Component):
             ("Refresh", Gtk.STOCK_REFRESH, None, "<Primary>R",
                 _("Refresh the view"),
                 self.on_menu_refresh_activate),
-
-            ("TabMenu", None, _("_Tabs")),
-            ("PrevTab",   None, _("_Previous Tab"), "<Ctrl><Alt>Page_Up",
-                _("Activate previous tab"),
-                self.on_prev_tab),
-            ("NextTab",   None, _("_Next Tab"), "<Ctrl><Alt>Page_Down",
-                _("Activate next tab"),
-                self.on_next_tab),
-            ("MoveTabPrev", None,
-                _("Move Tab _Left"), "<Ctrl><Alt><Shift>Page_Up",
-                _("Move current tab to left"),
-                self.on_move_tab_prev),
-            ("MoveTabNext", None,
-                _("Move Tab _Right"), "<Ctrl><Alt><Shift>Page_Down",
-                _("Move current tab to right"),
-                self.on_move_tab_next),
         )
         toggleactions = (
             ("Fullscreen", None, _("Fullscreen"), "F11",
@@ -328,12 +312,6 @@ class MeldWindow(gnomeglade.Component):
 
     def _update_page_action_sensitivity(self):
         current_page = self.notebook.get_current_page()
-        have_prev_tab = current_page > 0
-        have_next_tab = current_page < self.notebook.get_n_pages() - 1
-        self.actiongroup.get_action("PrevTab").set_sensitive(have_prev_tab)
-        self.actiongroup.get_action("NextTab").set_sensitive(have_next_tab)
-        self.actiongroup.get_action("MoveTabPrev").set_sensitive(have_prev_tab)
-        self.actiongroup.get_action("MoveTabNext").set_sensitive(have_next_tab)
 
         if current_page != -1:
             page = self.notebook.get_nth_page(current_page).pyobject
@@ -532,23 +510,6 @@ class MeldWindow(gnomeglade.Component):
     def on_toolbar_stop_clicked(self, *args):
         self.current_doc().stop()
 
-    def on_prev_tab(self, *args):
-        self.notebook.prev_page()
-
-    def on_next_tab(self, *args):
-        self.notebook.next_page()
-
-    def on_move_tab_prev(self, *args):
-        page_num = self.notebook.get_current_page()
-        child = self.notebook.get_nth_page(page_num)
-        page_num = page_num - 1 if page_num > 0 else 0
-        self.notebook.reorder_child(child, page_num)
-
-    def on_move_tab_next(self, *args):
-        page_num = self.notebook.get_current_page()
-        child = self.notebook.get_nth_page(page_num)
-        self.notebook.reorder_child(child, page_num + 1)
-
     def page_removed(self, page, status):
         if hasattr(page, 'scheduler'):
             self.scheduler.remove_scheduler(page.scheduler)
diff --git a/meld/ui/notebook.py b/meld/ui/notebook.py
index 8f70caf..916533b 100644
--- a/meld/ui/notebook.py
+++ b/meld/ui/notebook.py
@@ -14,6 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from gi.repository import Gdk
+from gi.repository import Gio
 from gi.repository import GObject
 from gi.repository import Gtk
 
@@ -31,9 +32,45 @@ class MeldNotebook(Gtk.Notebook):
         MeldNotebook { gtk-key-bindings: TabSwitchBindings; }
     """
 
+    ui = """
+        <?xml version="1.0" encoding="UTF-8"?>
+        <interface>
+          <menu id="tab-menu">
+            <item>
+              <attribute name="label">Move _Left</attribute>
+              <attribute name="action">popup.tabmoveleft</attribute>
+            </item>
+            <item>
+              <attribute name="label">Move _Right</attribute>
+              <attribute name="action">popup.tabmoveright</attribute>
+            </item>
+            <item>
+              <attribute name="label">_Close</attribute>
+              <attribute name="action">win.close</attribute>
+            </item>
+          </menu>
+        </interface>
+    """
+
     def __init__(self, *args, **kwargs):
         Gtk.Notebook.__init__(self, *args, **kwargs)
 
+        self.action_group = Gio.SimpleActionGroup()
+
+        actions = (
+            ("tabmoveleft", self.on_tab_move_left),
+            ("tabmoveright", self.on_tab_move_right),
+        )
+        for (name, callback) in actions:
+            action = Gio.SimpleAction.new(name, None)
+            action.connect('activate', callback)
+            self.action_group.add_action(action)
+
+        self.insert_action_group("popup", self.action_group)
+
+        builder = Gtk.Builder.new_from_string(self.ui, -1)
+        self.popup_menu = builder.get_object("tab-menu")
+
         provider = Gtk.CssProvider()
         provider.load_from_data(self.css)
         Gtk.StyleContext.add_provider_for_screen(
@@ -49,5 +86,43 @@ class MeldNotebook(Gtk.Notebook):
                 bindings, 'bind "<Alt>%d" { "tab-switch" (%d) };' % (key, i))
         self.connect('tab-switch', self.do_tab_switch)
 
+        self.connect('button-press-event', self.on_button_press_event)
+        self.connect('popup-menu', self.on_popup_menu)
+
     def do_tab_switch(self, notebook, page_num):
         notebook.set_current_page(page_num)
+
+    def on_popup_menu(self, widget, event=None):
+        self.action_group.lookup_action("tabmoveleft").set_enabled(
+            self.get_current_page() > 0)
+        self.action_group.lookup_action("tabmoveright").set_enabled(
+            self.get_current_page() < self.get_n_pages() - 1)
+
+        if event:
+            button = event.button
+            time = event.time
+        else:
+            button = 0
+            time = Gtk.get_current_event_time()
+        popup = Gtk.Menu.new_from_model(self.popup_menu)
+        popup.attach_to_widget(widget, None)
+        popup.show_all()
+        popup.popup(None, None, None, None, button, time)
+        return True
+
+    def on_button_press_event(self, widget, event):
+        if (event.triggers_context_menu() and
+                event.type == Gdk.EventType.BUTTON_PRESS):
+            return self.on_popup_menu(widget, event)
+        return False
+
+    def on_tab_move_left(self, *args):
+        page_num = self.get_current_page()
+        child = self.get_nth_page(page_num)
+        page_num = page_num - 1 if page_num > 0 else 0
+        self.reorder_child(child, page_num)
+
+    def on_tab_move_right(self, *args):
+        page_num = self.get_current_page()
+        child = self.get_nth_page(page_num)
+        self.reorder_child(child, page_num + 1)