added transparancey scale; added interactive debug button

src/core/widgets/transparency_scale.py

@@ -0,0 +1,48 @@
+# Python imports
+
+# Lib imports
+import gi
+gi.require_version('Gtk', '3.0')
+from gi.repository import Gtk
+
+# Application imports
+
+
+
+class TransparencyScale(Gtk.Scale):
+    def __init__(self):
+        super(TransparencyScale, self).__init__()
+
+
+        self._setup_styling()
+        self._setup_signals()
+        self._subscribe_to_events()
+        self._load_widgets()
+
+        self.show_all()
+
+
+    def _setup_styling(self):
+        self.set_digits(0)
+        self.set_value_pos(Gtk.PositionType.RIGHT)
+        self.add_mark(50.0, Gtk.PositionType.TOP, "50%")
+
+
+    def _setup_signals(self):
+        self.connect("value-changed", self._update_transparency)
+
+    def _subscribe_to_events(self):
+        ...
+
+    def _load_widgets(self):
+        adjust = self.get_adjustment()
+        adjust.set_lower(0)
+        adjust.set_upper(99)
+        adjust.set_value(settings.theming.transparency)
+        adjust.set_step_increment(1.0)
+
+    def _update_transparency(self, range):
+        event_system.emit("remove_transparency")
+        tp = int(range.get_value())
+        settings.theming.transparency = tp
+        event_system.emit("update_transparency")