Library: Port 'Color Dialog' to Python (#725)

Author: gregorni

src/Library/demos/Color Dialog/main.py

@@ -0,0 +1,46 @@
+import gi
+
+gi.require_version("Gtk", "4.0")
+from gi.repository import Gdk, Gio, Gtk
+import workbench
+
+
+color_dialog_button = workbench.builder.get_object("color_dialog_button")
+custom_button = workbench.builder.get_object("custom_button")
+
+color = Gdk.RGBA()
+color.parse("red")
+
+dialog_standard = Gtk.ColorDialog(
+    title="Select a color",
+    modal=True,
+    with_alpha=True,
+)
+
+color_dialog_button.set_dialog(dialog_standard)
+color_dialog_button.set_rgba(color)
+
+color_dialog_button.connect(
+    "notify::rgba",
+    lambda *_: print(
+        f"Color Dialog Button: The color selected is {color_dialog_button.get_rgba().to_string()}",
+    ),
+)
+
+dialog_custom = Gtk.ColorDialog(
+    title="Select a color",
+    modal=True,
+    with_alpha=False,
+)
+
+
+def on_color_selected(_dialog, _result):
+    color = _dialog.choose_rgba_finish(_result)
+    print(f"Custom Button: The color selected is {color.to_string()}")
+
+
+def on_clicked(_button):
+    dialog_custom.choose_rgba(workbench.window, None, None, on_color_selected)
+
+
+custom_button.connect("clicked", on_clicked)