IntRangeWidget with tuple and scalar traits

widget_int.py

"""IntWidget class.

Represents an unbounded int 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
#-----------------------------------------------------------------------------
from .widget import DOMWidget
from IPython.utils.traitlets import Unicode, CInt, Bool, Enum, Tuple, link

#-----------------------------------------------------------------------------
# Classes
#-----------------------------------------------------------------------------
class _IntWidget(DOMWidget):
    value = CInt(0, help="Int value", sync=True)
    disabled = Bool(False, help="Enable or disable user changes", sync=True)
    description = Unicode(help="Description of the value this widget represents", sync=True)


class _BoundedIntWidget(_IntWidget):
    step = CInt(1, help="Minimum step that the value can take (ignored by some views)", sync=True)
    max = CInt(100, help="Max value", sync=True)
    min = CInt(0, help="Min value", sync=True)

    def __init__(self, *pargs, **kwargs):
        """Constructor"""
        DOMWidget.__init__(self, *pargs, **kwargs)
        self.on_trait_change(self._validate, ['value', 'min', 'max'])

    def _validate(self, name, old, new):
        """Validate value, max, min."""
        if self.min > new or new > self.max:
            self.value = min(max(new, self.min), self.max)


class IntTextWidget(_IntWidget):
    _view_name = Unicode('IntTextView', sync=True)


class BoundedIntTextWidget(_BoundedIntWidget):
    _view_name = Unicode('IntTextView', sync=True)


class IntSliderWidget(_BoundedIntWidget):
    _view_name = Unicode('IntSliderView', sync=True)
    orientation = Enum([u'horizontal', u'vertical'], u'horizontal',
        help="Vertical or horizontal.", sync=True)
    range = Bool(False, help="Display a range selector", sync=True)
    readout = Bool(True, help="Display the current value of the slider next to it.", sync=True)


class IntProgressWidget(_BoundedIntWidget):
    _view_name = Unicode('ProgressView', sync=True)

class _IntRangeWidget(_IntWidget):
    value = Tuple(CInt, CInt, default_value=(0, 1), help="Low and high int values", sync=True)
    lower = CInt(0, help="Lower bound")
    upper = CInt(1, help="Upper bound")

    def __init__(self, *pargs, **kwargs):
        if set(['value', 'lower']) <= set(kwargs) or set(['value', 'upper']) <= set(kwargs):
            raise ValueError("Cannot specify both value and (lower, upper) for IntRange")

        DOMWidget.__init__(self, *pargs, **kwargs)

        def make_closure(targetobj, targetattr, src_pos=None, dest_pos=None):
            def update(name, old, new):
                if src_pos is None:
                    value = new
                else:
                    value = new[src_pos]
                if dest_pos is None:
                    setattr(targetobj, targetattr, value)
                else:
                    targetvalue = list(getattr(targetobj, targetattr))
                    targetvalue[dest_pos] = value
                    setattr(targetobj, targetattr, tuple(targetvalue))
            return update

        if 'value' in kwargs:
            self.lower, self.upper = self.value
        elif 'lower' in kwargs or 'upper' in kwargs:
            self.value = self.lower, self.upper

        self.on_trait_change(make_closure(self, 'value', dest_pos=0), 'lower')
        self.on_trait_change(make_closure(self, 'value', dest_pos=1), 'upper')
        self.on_trait_change(make_closure(self, 'lower', src_pos=0), 'value')
        self.on_trait_change(make_closure(self, 'upper', src_pos=1), 'value')


class _BoundedIntRangeWidget(_IntRangeWidget):
    step = CInt(1, help="Minimum step that the value can take (ignored by some views)", sync=True)
    max = CInt(100, help="Max value", sync=True)
    min = CInt(0, help="Min value", sync=True)

    def __init__(self, *pargs, **kwargs):
        """Constructor"""
        _IntRangeWidget.__init__(self, *pargs, **kwargs)
        self.on_trait_change(self._validate, ['value', 'min', 'max'])

    def _validate(self, name, old, new):
        """Validate min <= low <= high <= max"""
        if name == "value":
            low, high = new
        else:
            low, high = self.value
        low = max(low, self.min)
        high = min(high, self.max)
        self.value = (min(low, high), max(low, high))


class IntRangeSliderWidget(_BoundedIntRangeWidget):
    _view_name = Unicode('IntSliderView', sync=True)
    orientation = Enum([u'horizontal', u'vertical'], u'horizontal',
        help="Vertical or horizontal.", sync=True)
    range = Bool(True, help="Display a range selector", sync=True)
    readout = Bool(True, help="Display the current value of the slider next to it.", sync=True)