openlp/openlp/core/lib/listwidgetwithdnd.py

# -*- coding: utf-8 -*-
# vim: autoindent shiftwidth=4 expandtab textwidth=80 tabstop=4 softtabstop=4

###############################################################################
# OpenLP - Open Source Lyrics Projection                                      #
# --------------------------------------------------------------------------- #
# Copyright (c) 2008-2014 Raoul Snyman                                        #
# Portions copyright (c) 2008-2014 Tim Bentley, Gerald Britton, Jonathan      #
# Corwin, Samuel Findlay, Michael Gorven, Scott Guerrieri, Matthias Hub,      #
# Meinert Jordan, Armin Köhler, Erik Lundin, Edwin Lunando, Brian T. Meyer.   #
# Joshua Miller, Stevan Pettit, Andreas Preikschat, Mattias Põldaru,          #
# Christian Richter, Philip Ridout, Simon Scudder, Jeffrey Smith,             #
# Maikel Stuivenberg, Martin Thompson, Jon Tibble, Dave Warnock,              #
# Frode Woldsund, Martin Zibricky                                             #
# --------------------------------------------------------------------------- #
# This program is free software; you can redistribute it and/or modify it     #
# under the terms of the GNU General Public License as published by the Free  #
# Software Foundation; version 2 of the License.                              #
#                                                                             #
# 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.                                                               #
#                                                                             #
# 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                          #
###############################################################################
"""
Extend QListWidget to handle drag and drop functionality
"""
import os

from PyQt4 import QtCore, QtGui

from openlp.core.lib import Receiver

class ListWidgetWithDnD(QtGui.QListWidget):
    """
    Provide a list widget to store objects and handle drag and drop events
    """
    def __init__(self, parent=None, name=u''):
        """
        Initialise the list widget
        """
        QtGui.QListWidget.__init__(self, parent)
        self.mimeDataText = name
        assert(self.mimeDataText)

    def activateDnD(self):
        """
        Activate DnD of widget
        """
        self.setAcceptDrops(True)
        self.setDragDropMode(QtGui.QAbstractItemView.DragDrop)
        QtCore.QObject.connect(Receiver.get_receiver(),
            QtCore.SIGNAL(u'%s_dnd' % self.mimeDataText),
            self.parent().loadFile)

    def mouseMoveEvent(self, event):
        """
        Drag and drop event does not care what data is selected
        as the recipient will use events to request the data move
        just tell it what plugin to call
        """
        if event.buttons() != QtCore.Qt.LeftButton:
            event.ignore()
            return
        if not self.selectedItems():
            event.ignore()
            return
        drag = QtGui.QDrag(self)
        mimeData = QtCore.QMimeData()
        drag.setMimeData(mimeData)
        mimeData.setText(self.mimeDataText)
        drag.start(QtCore.Qt.CopyAction)

    def dragEnterEvent(self, event):
        if event.mimeData().hasUrls():
            event.accept()
        else:
            event.ignore()

    def dragMoveEvent(self, event):
        if event.mimeData().hasUrls():
            event.setDropAction(QtCore.Qt.CopyAction)
            event.accept()
        else:
            event.ignore()

    def dropEvent(self, event):
        """
        Receive drop event check if it is a file and process it if it is.

        ``event``
            Handle of the event pint passed
        """
        if event.mimeData().hasUrls():
            event.setDropAction(QtCore.Qt.CopyAction)
            event.accept()
            files = []
            for url in event.mimeData().urls():
                localFile = unicode(url.toLocalFile())
                if os.path.isfile(localFile):
                    files.append(localFile)
                elif os.path.isdir(localFile):
                    listing = os.listdir(localFile)
                    for file in listing:
                        files.append(os.path.join(localFile, file))
            Receiver.send_message(u'%s_dnd' % self.mimeDataText, files)
        else:
            event.ignore()