Source code for camelot.view.controls.delegates.floatdelegate

#  ============================================================================
#
#  Copyright (C) 2007-2013 Conceptive Engineering bvba. All rights reserved.
#  www.conceptive.be / info@conceptive.be
#
#  This file is part of the Camelot Library.
#
#  This file may be used under the terms of the GNU General Public
#  License version 2.0 as published by the Free Software Foundation
#  and appearing in the file license.txt included in the packaging of
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#  visit www.python-camelot.com or contact info@conceptive.be
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#  WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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#  ============================================================================
from PyQt4 import QtCore
from PyQt4.QtCore import Qt

from customdelegate import CustomDelegate, DocumentationMetaclass
from camelot.view.controls import editors
from camelot.core import constants
from camelot.core.utils import variant_to_pyobject
from camelot.view.proxy import ValueLoading

class FloatDelegate( CustomDelegate ):
    """Custom delegate for float values"""

    __metaclass__ = DocumentationMetaclass

    editor = editors.FloatEditor

    def __init__( self,
                 minimum=constants.camelot_minfloat,
                 maximum=constants.camelot_maxfloat,
                 parent=None,
                 unicode_format=None,
                 **kwargs ):
        CustomDelegate.__init__(self,
                                parent=parent,
                                minimum=minimum, maximum=maximum,
                                **kwargs )                   
        self.minimum = minimum
        self.maximum = maximum
        self.unicode_format = unicode_format
        self._locale = QtCore.QLocale()

    def paint( self, painter, option, index ):
        painter.save()
        self.drawBackground(painter, option, index)
        value = variant_to_pyobject(index.model().data(index, Qt.EditRole))
        field_attributes = variant_to_pyobject( index.model().data( index, Qt.UserRole ) )

        if field_attributes == ValueLoading:
            precision = 2
        else:
            precision = field_attributes.get('precision', 2)
            
        if value in (None, ValueLoading):
            value_str = ''
        elif self.unicode_format:
            value_str = self.unicode_format(value)
        else:
            value_str = unicode( self._locale.toString( float(value), 
                                                        'f', 
                                                        precision ) )

        self.paint_text( painter, option, index, value_str, horizontal_align=Qt.AlignRight )
        painter.restore()