Add Expander example

Closes #181

Author: cydanil

examples/expander_example.py

@@ -0,0 +1,47 @@
+import gi
+
+gi.require_version("Gtk", "3.0")
+from gi.repository import Gtk
+
+
+class ExpanderExample(Gtk.Window):
+    def __init__(self):
+        Gtk.Window.__init__(self, title="Expander Demo")
+
+        self.set_size_request(350, 100)
+
+        vbox = Gtk.Box(orientation=Gtk.Orientation.VERTICAL, spacing=6)
+        self.add(vbox)
+
+        text_expander = Gtk.Expander(
+                label="This expander displays additional information"
+        )
+        text_expander.set_expanded(True)
+        vbox.add(text_expander)
+
+        msg = """
+This message is quite long, complicated even:
+    - It has a list with a sublist:
+        - of 3 elements;
+        - taking several lines;
+        - with indentation.
+"""
+        details = Gtk.Label(label=msg)
+        text_expander.add(details)
+
+        widget_expander = Gtk.Expander(label="Expand for more controls")
+        vbox.add(widget_expander)
+
+        expander_hbox = Gtk.HBox()
+        widget_expander.add(expander_hbox)
+
+        expander_hbox.add(Gtk.Label(label="Text message"))
+        expander_hbox.add(Gtk.Button(label="Click me"))
+
+        self.show_all()
+
+
+win = ExpanderExample()
+win.connect("destroy", Gtk.main_quit)
+win.show_all()
+Gtk.main()

images/expander_example.png

@@ -0,0 +1,24 @@
+Expander
+========
+
+Expanders allow to dynamically hide or show information within a window or
+dialog. An expander can take a single widget that will be displayed when
+expanded.
+
+Expanders remain expanded until clicked again. When the state of an expander
+is changed, the "activate" signal is emitted.
+
+An expander can be programmatically expanded or collapsed by passing `True` or
+`False` to :meth:`Gtk.Expander.set_expanded`. Note that doing so causes the
+"activate" signal to be emitted.
+
+More than one widget, such as a :class:`Gtk.Label` and :class:`Gtk.Button`,
+can be added by appending them to a :class:`Gtk.Box`.
+
+Example
+^^^^^^^
+
+.. image:: ../images/expander_example.png
+
+.. literalinclude:: ../examples/expander_example.py
+    :linenos:

source/expander.txt

@@ -43,6 +43,7 @@ Contents:
    label
    entry
    button_widgets
+   expander
    progressbar
    spinner
    treeview