playlist: Create a new LabelFactory

For creating the labels used by the ColumnView columns

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

playlist/column.py

@@ -3,6 +3,33 @@ from lib import settings
 from gi.repository import Gtk, GLib
 import audio
 
+
+class LabelFactory(Gtk.SignalListItemFactory):
+    def __init__(self, xalign):
+        Gtk.SignalListItemFactory.__init__(self)
+        self.connect("setup", self.on_setup)
+        self.connect("bind", self.on_bind)
+        self.connect("unbind", self.on_unbind)
+        self.connect("teardown", self.on_teardown)
+        self.xalign = xalign
+
+    def get_track_text(self, track):
+        raise NotImplementedError
+
+    def on_setup(self, factory, listitem):
+        listitem.set_child(Gtk.Label(xalign=self.xalign))
+
+    def on_bind(self, factory, listitem):
+        text = self.get_track_text(listitem.get_item())
+        listitem.get_child().set_text(text)
+
+    def on_unbind(self, factory, listitem):
+        listitem.get_child().set_text("")
+
+    def on_teardown(self, factory, listitem):
+        listitem.set_child(None)
+
+
 class Column(Gtk.ColumnViewColumn):
     def __init__(self, title, field, width=-1, expand=False, align=0):
         Gtk.ColumnViewColumn.__init__(self)

playlist/test_column.py

@@ -4,6 +4,43 @@ from . import column
 from gi.repository import Gtk
 import unittest
 
+class FakeListItem:
+    def __init__(self): self.child = None
+    def get_item(self): return None
+    def get_child(self): return self.child
+    def set_child(self, child): self.child = child
+
+
+class TestLabelFactory(unittest.TestCase):
+    def test_init(self):
+        factory = column.LabelFactory(0.5)
+        self.assertIsInstance(factory, Gtk.SignalListItemFactory)
+        self.assertEqual(factory.xalign, 0.5)
+
+    def test_setup_teardown(self):
+        fake = FakeListItem()
+        factory = column.LabelFactory(0.5)
+
+        factory.on_setup(factory, fake)
+        self.assertIsInstance(fake.child, Gtk.Label)
+        self.assertEqual(fake.child.get_xalign(), 0.5)
+
+        factory.on_teardown(factory, fake)
+        self.assertIsNone(fake.child)
+
+    def test_bind_unbind(self):
+        fake = FakeListItem()
+        factory = column.LabelFactory(0.5)
+        factory.on_setup(factory, fake)
+
+        with self.assertRaises(NotImplementedError):
+            factory.on_bind(factory, fake)
+
+        fake.child.set_text("abcde")
+        factory.on_unbind(factory, fake)
+        self.assertEqual(fake.child.get_text(), "")
+
+
 class TestPlaylistColumn(unittest.TestCase):
     def tearDown(self):
         settings.reset()