audio: Create a menu button with volume controls

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

audio/menu.py

@@ -0,0 +1,47 @@
+# Copyright 2021 (c) Anna Schumaker.
+from lib import settings
+from gi.repository import Gtk
+
+class Button(Gtk.MenuButton):
+    def __init__(self):
+        Gtk.MenuButton.__init__(self)
+
+        settings.initialize("audio.volume", 1.0)
+        self.vol_img = Gtk.Image()
+        self.volume = Gtk.Scale.new_with_range(Gtk.Orientation.HORIZONTAL,
+                                               0.0, 1.0, 0.05)
+        self.volume.connect("value-changed", self.on_volume_changed)
+        self.volume.set_value(settings.get_float("audio.volume"))
+        self.volume.set_format_value_func(self.format_volume)
+        self.volume.set_draw_value(True)
+        self.on_volume_changed(self.volume)
+
+        self.grid = Gtk.Grid()
+        self.grid.attach(self.vol_img, 0, 1, 1, 1)
+        self.grid.attach(self.volume,  1, 1, 1, 1)
+        self.grid.add_css_class("large-icons")
+        self.grid.set_column_spacing(5)
+
+        self.popover = Gtk.Popover()
+        self.popover.set_child(self.grid)
+
+        self.set_popover(self.popover)
+        self.add_css_class("normal-icons")
+
+    def format_volume(self, scale, value):
+        return f"{int(value*100)}%"
+
+    def get_volume(self):
+        return self.volume.get_value()
+
+    def on_volume_changed(self, scale):
+        value = scale.get_value()
+        settings.set("audio.volume", value)
+        if value == 0:
+            self.vol_img.set_from_icon_name("audio-volume-muted-symbolic")
+        elif value < 1/3:
+            self.vol_img.set_from_icon_name("audio-volume-low-symbolic")
+        elif value < 2/3:
+            self.vol_img.set_from_icon_name("audio-volume-medium-symbolic")
+        else:
+            self.vol_img.set_from_icon_name("audio-volume-high-symbolic")

audio/test_menu.py

@@ -0,0 +1,65 @@
+# Copyright 2021 (c) Anna Schumaker.
+from . import menu
+from lib import settings
+from gi.repository import Gtk
+import unittest
+
+class TestAudioMenu(unittest.TestCase):
+    def setUp(self):
+        settings.reset()
+
+    def test_audio_menu_init(self):
+        button = menu.Button()
+
+        self.assertIsInstance(button, Gtk.MenuButton)
+        self.assertIsInstance(button.popover, Gtk.Popover)
+        self.assertIsInstance(button.grid, Gtk.Grid)
+
+        self.assertTrue(button.has_css_class("normal-icons"))
+        self.assertTrue(button.grid.has_css_class("large-icons"))
+
+        self.assertEqual(button.grid.get_column_spacing(), 5)
+        self.assertEqual(button.get_popover(), button.popover)
+        self.assertEqual(button.popover.get_child(), button.grid)
+
+    def test_audio_menu_volume_init(self):
+        button = menu.Button()
+        adjustment = button.volume.get_adjustment()
+
+        self.assertIsInstance(button.vol_img, Gtk.Image)
+        self.assertIsInstance(button.volume, Gtk.Scale)
+
+        self.assertTrue(button.volume.get_draw_value())
+
+        self.assertEqual(settings.get_float("audio.volume"), 1.0)
+        self.assertEqual(adjustment.get_lower(), 0.0)
+        self.assertEqual(adjustment.get_upper(), 1.0)
+        self.assertEqual(adjustment.get_step_increment(), 0.05)
+        self.assertEqual(adjustment.get_value(), 1.0)
+        self.assertEqual(button.vol_img.get_icon_name(), "audio-volume-high-symbolic")
+
+        self.assertIn(button.vol_img, button.grid)
+        self.assertIn(button.volume, button.grid)
+
+    def test_audio_menu_volume(self):
+        button = menu.Button()
+
+        button.volume.set_value(0)
+        self.assertEqual(button.vol_img.get_icon_name(), "audio-volume-muted-symbolic")
+        self.assertEqual(settings.get("audio.volume"), "0.0")
+        self.assertEqual(button.get_volume(), 0.0)
+
+        button.volume.set_value(0.3)
+        self.assertEqual(button.vol_img.get_icon_name(), "audio-volume-low-symbolic")
+        self.assertEqual(settings.get("audio.volume"), "0.3")
+        self.assertEqual(button.get_volume(), 0.3)
+
+        button.volume.set_value(0.6)
+        self.assertEqual(button.vol_img.get_icon_name(), "audio-volume-medium-symbolic")
+        self.assertEqual(settings.get("audio.volume"), "0.6")
+        self.assertEqual(button.get_volume(), 0.6)
+
+        button.volume.set_value(0.9)
+        self.assertEqual(button.vol_img.get_icon_name(), "audio-volume-high-symbolic")
+        self.assertEqual(settings.get("audio.volume"), "0.9")
+        self.assertEqual(button.get_volume(), 0.9)