1 files changed, 98 insertions, 0 deletions
diff --git a/examples/full-screen/calculator.py b/examples/full-screen/calculator.py
new file mode 100755
index 0000000..fda6567
--- /dev/null
+++ b/examples/full-screen/calculator.py
@@ -0,0 +1,98 @@
+#!/usr/bin/env python
+"""
+A simple example of a calculator program.
+This could be used as inspiration for a REPL.
+"""
+from prompt_toolkit.application import Application
+from prompt_toolkit.document import Document
+from prompt_toolkit.filters import has_focus
+from prompt_toolkit.key_binding import KeyBindings
+from prompt_toolkit.layout.containers import HSplit, Window
+from prompt_toolkit.layout.layout import Layout
+from prompt_toolkit.styles import Style
+from prompt_toolkit.widgets import SearchToolbar, TextArea
+
+help_text = """
+Type any expression (e.g. "4 + 4") followed by enter to execute.
+Press Control-C to exit.
+"""
+
+
+def main():
+    # The layout.
+    search_field = SearchToolbar()  # For reverse search.
+
+    output_field = TextArea(style="class:output-field", text=help_text)
+    input_field = TextArea(
+        height=1,
+        prompt=">>> ",
+        style="class:input-field",
+        multiline=False,
+        wrap_lines=False,
+        search_field=search_field,
+    )
+
+    container = HSplit(
+        [
+            output_field,
+            Window(height=1, char="-", style="class:line"),
+            input_field,
+            search_field,
+        ]
+    )
+
+    # Attach accept handler to the input field. We do this by assigning the
+    # handler to the `TextArea` that we created earlier. it is also possible to
+    # pass it to the constructor of `TextArea`.
+    # NOTE: It's better to assign an `accept_handler`, rather then adding a
+    #       custom ENTER key binding. This will automatically reset the input
+    #       field and add the strings to the history.
+    def accept(buff):
+        # Evaluate "calculator" expression.
+        try:
+            output = "\n\nIn:  {}\nOut: {}".format(
+                input_field.text, eval(input_field.text)
+            )  # Don't do 'eval' in real code!
+        except BaseException as e:
+            output = f"\n\n{e}"
+        new_text = output_field.text + output
+
+        # Add text to output buffer.
+        output_field.buffer.document = Document(
+            text=new_text, cursor_position=len(new_text)
+        )
+
+    input_field.accept_handler = accept
+
+    # The key bindings.
+    kb = KeyBindings()
+
+    @kb.add("c-c")
+    @kb.add("c-q")
+    def _(event):
+        "Pressing Ctrl-Q or Ctrl-C will exit the user interface."
+        event.app.exit()
+
+    # Style.
+    style = Style(
+        [
+            ("output-field", "bg:#000044 #ffffff"),
+            ("input-field", "bg:#000000 #ffffff"),
+            ("line", "#004400"),
+        ]
+    )
+
+    # Run application.
+    application = Application(
+        layout=Layout(container, focused_element=input_field),
+        key_bindings=kb,
+        style=style,
+        mouse_support=True,
+        full_screen=True,
+    )
+
+    application.run()
+
+
+if __name__ == "__main__":
+    main()