widget_string.py
111 lines
| 3.9 KiB
| text/x-python
|
PythonLexer
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r14283 | """StringWidget class. | ||
Represents a unicode string using a widget. | ||||
""" | ||||
#----------------------------------------------------------------------------- | ||||
# Copyright (c) 2013, the IPython Development Team. | ||||
# | ||||
# Distributed under the terms of the Modified BSD License. | ||||
# | ||||
# The full license is in the file COPYING.txt, distributed with this software. | ||||
#----------------------------------------------------------------------------- | ||||
#----------------------------------------------------------------------------- | ||||
# Imports | ||||
#----------------------------------------------------------------------------- | ||||
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r14391 | import inspect | ||
import types | ||||
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r14308 | from .widget import Widget | ||
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r14391 | from IPython.utils.traitlets import Unicode, Bool, List, Int | ||
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r14243 | |||
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r14283 | #----------------------------------------------------------------------------- | ||
# Classes | ||||
#----------------------------------------------------------------------------- | ||||
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r14243 | class StringWidget(Widget): | ||
target_name = Unicode('StringWidgetModel') | ||||
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r14291 | default_view_name = Unicode('TextBoxView') | ||
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r14283 | |||
# Keys | ||||
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r14403 | _keys = ['value', 'disabled', 'description'] | ||
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r14283 | value = Unicode(help="String value") | ||
disabled = Bool(False, help="Enable or disable user changes") | ||||
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r14292 | description = Unicode(help="Description of the value this widget represents") | ||
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r14391 | |||
def __init__(self, **kwargs): | ||||
super(StringWidget, self).__init__(**kwargs) | ||||
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r14402 | self._submission_callbacks = [] | ||
self.on_msg(self._handle_string_msg) | ||||
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r14391 | |||
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r14393 | def scroll_to_bottom(self): | ||
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r14403 | self._comm.send({"method": "scroll_to_bottom"}) | ||
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r14393 | |||
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r14402 | def on_click(self, callback, remove=False): | ||
"""Register a callback to execute when the button is clicked. The | ||||
callback can either accept no parameters or one sender parameter: | ||||
- callback() | ||||
- callback(sender) | ||||
If the callback has a sender parameter, the ButtonWidget instance that | ||||
called the callback will be passed into the method as the sender. | ||||
Parameters | ||||
---------- | ||||
remove : bool (optional) | ||||
Set to true to remove the callback from the list of callbacks.""" | ||||
if remove: | ||||
self._click_handlers.remove(callback) | ||||
elif not callback in self._click_handlers: | ||||
self._click_handlers.append(callback) | ||||
def _handle_string_msg(self, content): | ||||
"""Handle a msg from the front-end | ||||
Parameters | ||||
---------- | ||||
content: dict | ||||
Content of the msg.""" | ||||
if 'event' in content and content['event'] == 'submit': | ||||
self._handle_submit() | ||||
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r14391 | def on_submit(self, callback, remove=False): | ||
"""Register a callback to handle text submission (triggered when the | ||||
user clicks enter). | ||||
Parameters | ||||
callback: Method handle | ||||
Function to be called when the text has been submitted. Function | ||||
can have two possible signatures: | ||||
callback() | ||||
callback(sender) | ||||
remove: bool (optional) | ||||
Whether or not to unregister the callback""" | ||||
if remove and callback in self._submission_callbacks: | ||||
self._submission_callbacks.remove(callback) | ||||
elif not remove and not callback in self._submission_callbacks: | ||||
self._submission_callbacks.append(callback) | ||||
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r14402 | def _handle_submit(self): | ||
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r14391 | """Handles when a string widget view is submitted.""" | ||
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r14402 | for handler in self._submission_callbacks: | ||
if callable(handler): | ||||
argspec = inspect.getargspec(handler) | ||||
nargs = len(argspec[0]) | ||||
# Bound methods have an additional 'self' argument | ||||
if isinstance(handler, types.MethodType): | ||||
nargs -= 1 | ||||
# Call the callback | ||||
if nargs == 0: | ||||
handler() | ||||
elif nargs == 1: | ||||
handler(self) | ||||
else: | ||||
raise TypeError('StringWidget submit callback must ' \ | ||||
'accept 0 or 1 arguments.') | ||||