Library: Port 'Wallpaper' to Python (#814)

Author: gregorni

src/Library/demos/Wallpaper/main.py

@@ -0,0 +1,35 @@
+import gi
+
+gi.require_version("Xdp", "1.0")
+gi.require_version("XdpGtk4", "1.0")
+from gi.repository import Gio, Xdp, XdpGtk4
+import workbench
+
+portal = Xdp.Portal()
+parent = XdpGtk4.parent_new_gtk(workbench.window)
+button = workbench.builder.get_object("button")
+
+uri = workbench.resolve("./wallpaper.png")
+
+
+def on_wallpaper_set(_portal, result):
+    success = _portal.set_wallpaper_finish(result)
+    if success:
+        print("Wallpaper set successfully")
+    else:
+        print("Could not set wallpaper")
+
+
+def on_clicked(_button):
+    portal.set_wallpaper(
+        parent,
+        uri,
+        Xdp.WallpaperFlags.PREVIEW
+        | Xdp.WallpaperFlags.BACKGROUND
+        | Xdp.WallpaperFlags.LOCKSCREEN,
+        None,
+        on_wallpaper_set,
+    )
+
+
+button.connect("clicked", on_clicked)