first draft of menu tutorial example

--HG--
branch : feature-sphinx

1 files changed, 76 insertions, 0 deletions

diff --git a/docs/tutorial/menu.py b/docs/tutorial/menu.py
new file mode 100644
index 0000000..a44015a
--- /dev/null
+++ b/docs/tutorial/menu.py
@@ -0,0 +1,76 @@
+import urwid
+
+inventory = set()
+loop = urwid.MainLoop(None)
+
+class SubMenu(urwid.WidgetWrap):
+    def __init__(self, title, menu):
+        super(SubMenu, self).__init__(
+            urwid.SelectableIcon(u" > go to " + title, 1))
+        self.menu = menu
+
+    def keypress(self, size, key):
+        if key not in (' ', 'enter'):
+            return key
+        loop.widget = self.menu
+
+class Thing(urwid.WidgetWrap):
+    def __init__(self, name):
+        super(Thing, self).__init__(
+            urwid.SelectableIcon(u" * take " + name, 1))
+        self.name = name
+
+    def keypress(self, size, key):
+        if key not in (' ', 'enter'):
+            return key
+        self._w = urwid.Text(u" - " + self.name + " (taken)")
+        inventory.add(self.name)
+        if inventory >= set([u'sugar', u'lemon', u'jug']):
+            raise urwid.ExitMainLoop()
+        return 'up' # move selection off this item
+
+class Menu(urwid.ListBox):
+    def __init__(self, title, children):
+        super(Menu, self).__init__(urwid.SimpleListWalker([
+            urwid.Text(u"Location: " + title),
+            urwid.Divider()] + list(children)))
+        self.title = title
+
+    def set_parent(self, sub_menu):
+        self.body[2:2] = [sub_menu]
+
+def menu(title, *contents):
+    """Create menus and links back to parent menus"""
+    menu_full = Menu(title, contents)
+    sub_menu = SubMenu(title, menu_full)
+    for child in contents:
+        child_menu = getattr(child, 'menu', None)
+        if child_menu:
+            child_menu.set_parent(sub_menu)
+    return sub_menu
+
+menu_top = menu(u'porch',
+    menu(u'kitchen',
+        menu(u'refrigerator'),
+        menu(u'cupboard',
+            Thing(u'jug'),
+        ),
+    ),
+    menu(u'garden',
+        menu(u'tree',
+            Thing(u'lemon'),
+            Thing(u'bird'),
+        ),
+    ),
+    menu(u'street',
+        menu(u'store',
+            Thing(u'sugar'),
+            ),
+        menu(u'lake',
+            menu(u'beach'),
+            ),
+        ),
+    )
+loop.widget = menu_top.menu
+loop.run()
+print u"Congratulations, you can make lemonade!"