Source code for enaml.widgets.bounded_datetime

#  Copyright (c) 2011, Enthought, Inc.
#  All rights reserved.
from datetime import datetime as py_datetime

from dateutil.parser import parse as parse_iso_dt
from traits.api import Property, BaseInstance, on_trait_change

from enaml.core.trait_types import Bounded

from .control import Control

#: A custom trait which validates Python datetime instances.
Datetime = BaseInstance(py_datetime)

[docs]class BoundedDatetime(Control): """ A base class for use with widgets that edit a Python datetime.datetime object bounded between minimum and maximum values. This class is not meant to be used directly. """ #: The minimum datetime available in the datetime edit. If not #: defined then the default value is midnight September 14, 1752. minimum = Property(Datetime, depends_on ='_minimum') #: The internal minimum datetime storage _minimum = Datetime(py_datetime(1752, 9, 14, 0, 0, 0, 0)) #: The maximum datetime available in the datetime edit. If not #: defined then the default value is the second before midnight #: December 31, 7999. maximum = Property(Datetime, depends_on ='_maximum') #: The internal maximum datetime storage _maximum = Datetime(py_datetime(7999, 12, 31, 23, 59, 59, 999000)) #: The currently selected date. Default is The #: value is bounded between :attr:`minimum` and :attr:`maximum`. datetime = Bounded(Datetime(, low='minimum', high='maximum') #-------------------------------------------------------------------------- # Initialization #--------------------------------------------------------------------------
[docs] def snapshot(self): """ Return a dictionary which contains all the state necessary to initialize a client widget. """ snap = super(BoundedDatetime, self).snapshot() snap['minimum'] = self.minimum.isoformat() snap['maximum'] = self.maximum.isoformat() snap['datetime'] = self.datetime.isoformat() return snap
[docs] def bind(self): """ A method called after initialization which allows the widget to bind any event handlers necessary. """ super(BoundedDatetime, self).bind() otc = self.on_trait_change otc(self._send_minimum, 'minimum') otc(self._send_maximum, 'maximum') otc(self._send_datetime, 'datetime') #-------------------------------------------------------------------------- # Message Handling #--------------------------------------------------------------------------
[docs] def on_action_datetime_changed(self, content): """ The handler for the 'datetime_changed' action sent from the client widget. """ datetime = parse_iso_dt(content['datetime']) self.set_guarded(datetime=datetime)
def _send_minimum(self): """ Send the minimum datetime to the client widget. """ content = {'minimum': self.minimum.isoformat()} self.send_action('set_minimum', content) def _send_maximum(self): """ Send the maximum datetime to the client widget. """ content = {'maximum': self.maximum.isoformat()} self.send_action('set_maximum', content) def _send_datetime(self): """ Send the current datetime to the client widget. """ if 'datetime' not in self.loopback_guard: content = {'datetime': self.datetime.isoformat()} self.send_action('set_datetime', content) #-------------------------------------------------------------------------- # Properties #-------------------------------------------------------------------------- def _get_minimum(self): """ The property getter for the minimum datetime. """ return self._minimum def _set_minimum(self, datetime): """ The property setter for the minimum datetime. If the new minimum is greater than the current maximum, then the maximum will be adjusted up. """ if datetime > self._maximum: self._maximum = datetime self._minimum = datetime def _get_maximum(self): """ The property getter for the maximum datetime. """ return self._maximum def _set_maximum(self, datetime): """ The property setter for the maximum datetime. If the new maximum is less than the current minimum, then the minimum will be ajusted down. """ if datetime < self._minimum: self._minimum = datetime self._maximum = datetime #-------------------------------------------------------------------------- # Private API #-------------------------------------------------------------------------- @on_trait_change('minimum, maximum') def _adapt_datetime(self): """ Actively adapt the datetime to lie within the boundaries. """ self.datetime = min(max(self.datetime, self.minimum), self.maximum)