ugly, refactor required

res/layouts/pages/settings-audio.xml

@@ -0,0 +1,23 @@
+<panel size='400' color='0' interval='1'>
+    <label id='l_master'>-</label>
+    <trackbar min='0' max='1' value='1' step='0.01' track-width='5' 
+        consumer='on_master_change'
+        supplier='core.get_setting("audio.volume-master")'/>
+    <label id='l_regular'>-</label>
+    <trackbar min='0' max='1' value='1' step='0.01' track-width='5' 
+        consumer='on_regular_change'
+        supplier='core.get_setting("audio.volume-regular")'/>
+    <label id='l_ui'>-</label>
+    <trackbar min='0' max='1' value='1' step='0.01' track-width='5' 
+        consumer='on_ui_change'
+        supplier='core.get_setting("audio.volume-ui")'/>
+    <label id='l_ambient'>-</label>
+    <trackbar min='0' max='1' value='1' step='0.01' track-width='5' 
+        consumer='on_ambient_change'
+        supplier='core.get_setting("audio.volume-ambient")'/>
+    <label id='l_music'>-</label>
+    <trackbar min='0' max='1' value='1' step='0.01' track-width='5' 
+        consumer='on_music_change'
+        supplier='core.get_setting("audio.volume-music")'/>
+    <button padding='10' onclick='menu:back()'>@Back</button>
+</panel>

res/layouts/pages/settings-audio.xml.lua

@@ -0,0 +1,37 @@
+function on_open()
+    on_master_change()
+    on_regular_change()
+    on_ui_change()
+    on_ambient_change()
+    on_music_change()
+end
+
+function on_volume_change(setting, label, name, val)
+    if val ~= nil then
+        core.set_setting(setting, val)
+    end
+    label.text = (
+        gui.str(name, "settings")..": "..
+        core.str_setting(setting)
+    )
+end
+
+function on_master_change(val)
+    on_volume_change("audio.volume-master", document.l_master, "Master Volume", val)
+end
+
+function on_regular_change(val)
+    on_volume_change("audio.volume-regular", document.l_regular, "Regular Sounds", val)
+end
+
+function on_ui_change(val)
+    on_volume_change("audio.volume-ui", document.l_ui, "UI Sounds", val)
+end
+
+function on_ambient_change(val)
+    on_volume_change("audio.volume-ambient", document.l_ambient, "Ambient", val)
+end
+
+function on_music_change(val)
+    on_volume_change("audio.volume-music", document.l_music, "Music", val)
+end