AbstractFieldDelegate.py

##############################################################################
#
# Copyright (c) 2008 Albert Cervera i Areny <albert@nan-tic.com>
#
# WARNING: This program as such is intended to be used by professional
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#
# This program is Free Software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
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# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
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##############################################################################

from Koo import Rpc
from FieldPreferencesDialog import *
from PyQt4.QtGui import *
from PyQt4.QtCore import *

## @brief AbstractFieldDelegate is the base class for all delegates used in Koo.
# Delegates are used by editable lists but could be used by any Model/View based
# widget.
class AbstractFieldDelegate(QStyledItemDelegate):
        ## @brief Creates a new Delegate. 
        # 'attributes' is a dictionary with attributes that apply to the field such
        # as 'readonly' or 'required'.
        def __init__(self, parent, attributes):
                QStyledItemDelegate.__init__(self, parent)
                self.name = attributes['name']
                self.attributes = attributes
                self.colors = {
                        'invalid'  : '#FF6969',
                        'readonly' : '#e3e3e3', 
                        'required' : '#ddddff', 
                        'normal'   : 'white'
                }
                self.defaultMenuEntries = [
                        #(_('Set to default value'), self.setToDefault, 1),
                ]

        def createEditor(self, parent, option, index):
                # We expect a KooModel here
                model = index.model().recordFromIndex( index )
                if model and not model.isFieldValid( self.name ):
                        name = 'invalid'
                elif self.attributes.get('readonly', False):
                        name = 'readonly'
                elif self.attributes.get('required', False):
                        name = 'required'
                else:
                        name = 'normal'
                editor = QStyledItemDelegate.createEditor( self, parent, option, index )
                color = QColor( self.colors.get( name, 'white' ) )
                palette = QPalette()
                palette.setColor(QPalette.Base, color)
                editor.setPalette(palette);
                return editor

        ## @brief Use this function to return the menu entries your delegate wants to show
        # just before the context menu is shown. Return a list of tuples in the form:
        # [ (_('Menu text'), function/slot to connect the entry, True (for enabled) or False (for disabled) )] 
        def menuEntries(self, record):
                return []

        ## @brief Shows a popup menu with default and widget specific
        # entries.
        def showPopupMenu(self, parent, position):
                # parent is supposed to be a QAbstractItemView
                index = parent.indexAt( parent.mapFromGlobal( position ) )
                if not index or not index.isValid():
                        return
                record = index.model().recordFromIndex( index )

                entries = self.defaultMenuEntries[:]
                new = self.menuEntries( record )
                if len(new) > 0:
                        entries = entries + [(None, None, None)] + new
                if not entries:
                        return
                menu = QMenu( parent )
                for title, slot, enabled in entries:
                        if title:
                                item = QAction( title, menu )
                                if slot:
                                        self.connect( item, SIGNAL("triggered()"), slot )
                                item.setEnabled( enabled )
                                menu.addAction( item )
                        else:
                                menu.addSeparator()
                menu.popup( position )

        ## @brief Sets the default value to the field.
        #
        # Note that this requires a call to the server.
        def setToDefault(self):
                try:
                        model = self.record.group.resource
                        res = Rpc.session.call('/object', 'execute', model, 'default_get', [self.attrs['name']])
                        self.record.setValue(self.name, res.get(self.name, False))
                        self.display()
                except:
                        QMessageBox.warning(None, _('Operation not permited'), _('You can not set to the default value here !') )
                        return False