Add an example

examples/full-screen/simple-demos/word-wrapping.py

@@ -0,0 +1,146 @@
+#!/usr/bin/env python
+"""
+An example of a BufferControl in a full screen layout that offers auto
+completion.
+
+Important is to make sure that there is a `CompletionsMenu` in the layout,
+otherwise the completions won't be visible.
+"""
+
+from prompt_toolkit.application import Application
+from prompt_toolkit.buffer import Buffer
+from prompt_toolkit.filters import Condition
+from prompt_toolkit.formatted_text import HTML, to_formatted_text
+from prompt_toolkit.key_binding import KeyBindings
+from prompt_toolkit.layout.containers import Float, FloatContainer, HSplit, Window
+from prompt_toolkit.layout.controls import BufferControl, FormattedTextControl
+from prompt_toolkit.layout.layout import Layout
+from prompt_toolkit.layout.menus import CompletionsMenu
+
+LIPSUM = " ".join(
+    """\
+Lorem ipsum dolor sit amet, consectetur adipiscing elit.  Maecenas
+quis interdum enim. Nam viverra, mauris et blandit malesuada, ante est bibendum
+mauris, ac dignissim dui tellus quis ligula. Aenean condimentum leo at
+dignissim placerat. In vel dictum ex, vulputate accumsan mi. Donec ut quam
+placerat massa tempor elementum. Sed tristique mauris ac suscipit euismod. Ut
+tempus vehicula augue non venenatis. Mauris aliquam velit turpis, nec congue
+risus aliquam sit amet. Pellentesque blandit scelerisque felis, faucibus
+consequat ante. Curabitur tempor tortor a imperdiet tincidunt. Nam sed justo
+sit amet odio bibendum congue. Quisque varius ligula nec ligula gravida, sed
+convallis augue faucibus. Nunc ornare pharetra bibendum. Praesent blandit ex
+quis sodales maximus.""".split("\n")
+)
+
+
+def get_line_prefix(lineno, wrap_count):
+    if wrap_count == 0:
+        return HTML('[%s] <style bg="orange" fg="black">--&gt;</style> ') % lineno
+
+    text = str(lineno) + "-" + "*" * (lineno // 2) + ": "
+    return HTML('[%s.%s] <style bg="ansigreen" fg="ansiblack">%s</style>') % (
+        lineno,
+        wrap_count,
+        text,
+    )
+
+
+# Global wrap lines flag.
+wrap_lines = True
+
+
+# The layout
+buff = Buffer(complete_while_typing=True)
+buff.text = LIPSUM
+
+
+body = FloatContainer(
+    content=HSplit(
+        [
+            Window(
+                FormattedTextControl(
+                    'Press "q" to quit. Press "w" to enable/disable wrapping.'
+                ),
+                height=1,
+                style="reverse",
+            ),
+            # Break words
+            Window(
+                BufferControl(buffer=buff),
+                wrap_lines=Condition(lambda: wrap_lines),
+                word_wrap=False,
+            ),
+            # Default word wrapping
+            Window(
+                BufferControl(buffer=buff),
+                wrap_lines=Condition(lambda: wrap_lines),
+                word_wrap=True,
+            ),
+            # Add a marker to signify continuation
+            Window(
+                BufferControl(buffer=buff),
+                wrap_lines=True,
+                wrap_finder=Window._whitespace_wrap_finder(
+                    lambda n: [] if n else to_formatted_text(LIPSUM),
+                    continuation=to_formatted_text(" ⮠"),
+                ),
+                get_line_prefix=lambda lineno, wrap_count: to_formatted_text("    ⭢ ")
+                if wrap_count
+                else [],
+            ),
+            # Truncating (only wrap the first timle around)
+            Window(
+                BufferControl(buffer=buff),
+                wrap_lines=True,
+                wrap_finder=lambda lineno,
+                wrap_count,
+                start,
+                end,
+                fallback=Window._whitespace_wrap_finder(
+                    lambda n: [] if n else to_formatted_text(LIPSUM),
+                ): (end - 3, -1, "...")
+                if wrap_count > 0
+                else fallback(lineno, wrap_count, start, end),
+            ),
+        ]
+    ),
+    floats=[
+        Float(
+            xcursor=True,
+            ycursor=True,
+            content=CompletionsMenu(max_height=16, scroll_offset=1),
+        )
+    ],
+)
+
+
+# Key bindings
+kb = KeyBindings()
+
+
+@kb.add("q")
+@kb.add("c-c")
+def _(event):
+    "Quit application."
+    event.app.exit()
+
+
+@kb.add("w")
+def _(event):
+    "Disable/enable wrapping."
+    global wrap_lines
+    wrap_lines = not wrap_lines
+
+
+# The `Application`
+application = Application(
+    layout=Layout(body), key_bindings=kb, full_screen=True, mouse_support=True
+)
+
+
+def run():
+    application.run()
+
+
+if __name__ == "__main__":
+    run()