autohide ScrolledToolbar's arrows

1 files changed, 60 insertions, 18 deletions

diff --git a/common/Util/ScrolledToolbar.py b/common/Util/ScrolledToolbar.py
index c9512cc..415797f 100644
--- a/common/Util/ScrolledToolbar.py
+++ b/common/Util/ScrolledToolbar.py
@@ -6,7 +6,8 @@ class ScrollButton(gtk.ToolButton):
     def __init__(self, icon_name):
         gtk.ToolButton.__init__(self)
 
-        icon = Icon(icon_name = icon_name, icon_size=gtk.ICON_SIZE_SMALL_TOOLBAR)
+        icon = Icon(icon_name = icon_name,
+                icon_size=gtk.ICON_SIZE_SMALL_TOOLBAR)
         # The alignment is a hack to work around gtk.ToolButton code
         # that sets the icon_size when the icon_widget is a gtk.Image
         alignment = gtk.Alignment(0.5, 0.5)
@@ -14,34 +15,53 @@ class ScrollButton(gtk.ToolButton):
         self.set_icon_widget(alignment)
         
 class ScrolledToolbar(gtk.EventBox):
-    def __init__(self):
+    def __init__(self, arrows_policy = gtk.POLICY_AUTOMATIC):
         gtk.EventBox.__init__(self)
+        self._viewport = None
+        self._abox = None
+        self._aviewport = None
+        self._aviewport_sig = None
+        self._arrows_policy = arrows_policy
+        self._scrollLeft = None
+        self._scrollRight = None
 
         box = gtk.HBox()
+        if self._arrows_policy == gtk.POLICY_AUTOMATIC:
+            box.connect("size-allocate", self._box_allocate_cb)
         self.add(box)
 
-        self._scrollLeft = ScrollButton('go-left')
-        self._scrollLeft.connect( "clicked", self._scroll_cb, "left" )
-        box.pack_start( self._scrollLeft, False, False )
+        if self._arrows_policy != gtk.POLICY_NEVER:
+            self._scrollLeft = ScrollButton('go-left')
+            self._scrollLeft.connect( "clicked", self._scroll_cb, "left" )
+            box.pack_start(self._scrollLeft, False, False, 0)
 
         self._scrolledWindow = gtk.ScrolledWindow()
-        self._scrolledWindow.set_policy(gtk.POLICY_ALWAYS, gtk.POLICY_NEVER)
+        self._scrolledWindow.set_policy(gtk.POLICY_AUTOMATIC, gtk.POLICY_NEVER)
         self._scrolledWindow.connect('scroll-event', self._scroll_event_cb)
-        box.pack_start( self._scrolledWindow )
+        box.pack_start(self._scrolledWindow, True, True, 0)
         self._hadjustment = self._scrolledWindow.get_hadjustment()
         self._hadjustment.connect( "changed", self._scroll_changed_cb )
         self._hadjustment.connect( "value-changed", self._scroll_changed_cb )
 
-        self._scrollRight = ScrollButton('go-right')
-        self._scrollRight.connect( "clicked", self._scroll_cb, "right" )
-        box.pack_start(self._scrollRight, False, False)
+        if self._arrows_policy != gtk.POLICY_NEVER:
+            self._scrollRight = ScrollButton('go-right')
+            self._scrollRight.connect( "clicked", self._scroll_cb, "right" )
+            box.pack_start(self._scrollRight, False, False, 0)
 
     def modify_bg(self, state, bg):
         gtk.EventBox.modify_bg(self, state, bg)
         self._viewport.get_parent().modify_bg(state, bg)
 
     def set_viewport(self, widget):
+        if widget == self._viewport: return
+        if self._viewport and self._aviewport_sig:
+            self._viewport.disconnect(self._aviewport_sig)
         self._viewport = widget
+
+        if self._arrows_policy == gtk.POLICY_AUTOMATIC:
+            self._aviewport_sig = self._viewport.connect("size-allocate",
+                    self._viewport_allocate_cb)
+
         self._scrolledWindow.add_with_viewport(widget)
 
     def get_viewport_allocation(self):
@@ -52,6 +72,25 @@ class ScrolledToolbar(gtk.EventBox):
     def get_adjustment(self):
         return self._hadjustment
 
+    def _box_allocate_cb(self, w, a):
+        self._abox = a
+        self._update_arrows()
+
+    def _viewport_allocate_cb(self, w, a):
+        self._aviewport = a
+        self._update_arrows()
+
+    def _update_arrows(self):
+        if not self._abox or not self._aviewport: return
+
+        if self._abox.width < self._aviewport.width:
+            self._scrollLeft.show()
+            self._scrollRight.show()
+        else:
+            self._scrollLeft.hide()
+            self._scrollRight.hide()
+
+
     def _scroll_event_cb(self, widget, event):
         if event.direction == gtk.gdk.SCROLL_UP: event.direction = gtk.gdk.SCROLL_LEFT
         if event.direction == gtk.gdk.SCROLL_DOWN: event.direction = gtk.gdk.SCROLL_RIGHT
@@ -67,12 +106,15 @@ class ScrolledToolbar(gtk.EventBox):
 
     def _scroll_changed_cb( self, widget ):
         val = self._hadjustment.get_value()
-        if val == 0:
-            self._scrollLeft.set_sensitive( False )
-        else:
-            self._scrollLeft.set_sensitive( True )
+        if self._scrollLeft:
+            if val == 0:
+                self._scrollLeft.set_sensitive( False )
+            else:
+                self._scrollLeft.set_sensitive( True )
 
-        if val >= self._hadjustment.get_property( "upper" ) - self._hadjustment.get_property("page_size"):
-            self._scrollRight.set_sensitive( False )
-        else:
-            self._scrollRight.set_sensitive( True )
+        if self._scrollRight:
+            if val >= self._hadjustment.get_property( "upper" ) - \
+                    self._hadjustment.get_property("page_size"):
+                self._scrollRight.set_sensitive( False )
+            else:
+                self._scrollRight.set_sensitive( True )