audio: Add a custom VolumeScale widget

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

audio/scale.py

@@ -59,6 +59,20 @@ class SeekScale(ScalePlus):
         return GLib.SOURCE_CONTINUE
 
 
+class VolumeScale(ScalePlus):
+    def __init__(self, player):
+        ScalePlus.__init__(self, 0.0, 1.0, 0.05, 0.25)
+        self.player = player
+        self.set_value(player.get_volume())
+
+    def do_change_value(self, scroll, value):
+        self.set_value(value)
+        self.player.set_volume(value)
+
+    def format_value(self, scale, value):
+        return f"{int(value * 100)}%"
+
+
 class ScaleButton(Gtk.Button):
     def __init__(self, scale, icon):
         Gtk.Button.__init__(self)

audio/test_scale.py

@@ -6,14 +6,17 @@ from gi.repository import Gst
 from . import scale
 
 class FakePlayer(GObject.GObject):
-    def __init__(self, position, duration):
+    def __init__(self, position, duration, volume):
         GObject.GObject.__init__(self)
         self.pos = position
         self.dur = duration
+        self.vol = volume
 
     def position(self): return self.pos
     def duration(self): return self.dur
     def seek(self, value): self.seek_val = value
+    def set_volume(self, volume): self.vol = volume
+    def get_volume(self): return self.vol
 
 
 class TestScalePlus(unittest.TestCase):
@@ -67,7 +70,7 @@ class TestScalePlus(unittest.TestCase):
 
 class TestSeekScale(unittest.TestCase):
     def test_seek_scale_init(self):
-        fake = FakePlayer(0, 5 * Gst.SECOND)
+        fake = FakePlayer(0, 5 * Gst.SECOND, 1)
         seek = scale.SeekScale(fake)
         adj  = seek.get_adjustment()
 
@@ -82,7 +85,7 @@ class TestSeekScale(unittest.TestCase):
         self.assertEqual(adj.get_page_increment(), 30 * Gst.SECOND)
 
     def test_seek_scale_update(self):
-        fake = FakePlayer(3 * Gst.SECOND, 15 * Gst.SECOND)
+        fake = FakePlayer(3 * Gst.SECOND, 15 * Gst.SECOND, 1)
         seek = scale.SeekScale(fake)
         adj  = seek.get_adjustment()
 
@@ -93,7 +96,7 @@ class TestSeekScale(unittest.TestCase):
         self.assertEqual(adj.get_upper(), 15 * Gst.SECOND)
 
     def test_seek_scale_values(self):
-        fake = FakePlayer(0, 15 * Gst.SECOND)
+        fake = FakePlayer(0, 15 * Gst.SECOND, 1)
         seek = scale.SeekScale(fake)
 
         seek.update()
@@ -106,6 +109,37 @@ class TestSeekScale(unittest.TestCase):
         self.assertEqual(fake.seek_val, 0)
 
 
+class TestVolumeScale(unittest.TestCase):
+    def test_volume_scale_init(self):
+        fake = FakePlayer(0, 5 * Gst.SECOND, 1.0)
+        volume = scale.VolumeScale(fake)
+        adj = volume.get_adjustment()
+
+        self.assertIsInstance(volume, scale.ScalePlus)
+        self.assertEqual(volume.player, fake)
+        self.assertEqual(adj.get_value(), 1.0)
+        self.assertEqual(adj.get_lower(), 0.0)
+        self.assertEqual(adj.get_upper(), 1.0)
+        self.assertEqual(adj.get_step_increment(), 0.05)
+        self.assertEqual(adj.get_page_increment(), 0.25)
+
+        fake.set_volume(0.5)
+        vol2 = scale.VolumeScale(fake)
+        self.assertEqual(vol2.get_value(), 0.5)
+
+    def test_volume_scale_values(self):
+        fake = FakePlayer(0, 15 * Gst.SECOND, 0.5)
+        volume = scale.VolumeScale(fake)
+
+        volume.increment()
+        self.assertEqual(fake.get_volume(), 0.55)
+        self.assertEqual(volume.format_value(volume, 0.55), "55%")
+
+        volume.decrement()
+        self.assertEqual(fake.get_volume(), 0.50)
+        self.assertEqual(volume.format_value(volume, 0.50), "50%")
+
+
 class TestScaleButton(unittest.TestCase):
     def test_scale_button(self):
         splus = scale.ScalePlus(0, 5, 1, 1)