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#!/usr/bin/env python
#############################################################################
##
## Copyright (C) 2013 Riverbank Computing Limited
## Copyright (C) 2010 Darryl Wallace <wallacdj@gmail.com>.
## Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
## All rights reserved.
##
## This file is part of the examples of PyQt.
##
## $QT_BEGIN_LICENSE:BSD$
## You may use this file under the terms of the BSD license as follows:
##
## "Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions are
## met:
## * Redistributions of source code must retain the above copyright
## notice, this list of conditions and the following disclaimer.
## * Redistributions in binary form must reproduce the above copyright
## notice, this list of conditions and the following disclaimer in
## the documentation and/or other materials provided with the
## distribution.
## * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
## the names of its contributors may be used to endorse or promote
## products derived from this software without specific prior written
## permission.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
## $QT_END_LICENSE$
##
#############################################################################
from PyQt5.QtCore import (pyqtSignal, QAbstractListModel, QDir, QLibraryInfo,
QModelIndex, Qt)
from PyQt5.QtWidgets import (QApplication, QGridLayout, QLabel, QLineEdit,
QListView, QSizePolicy, QTextBrowser, QWidget)
class FileListModel(QAbstractListModel):
numberPopulated = pyqtSignal(int)
def __init__(self, parent=None):
super(FileListModel, self).__init__(parent)
self.fileCount = 0
self.fileList = []
def rowCount(self, parent=QModelIndex()):
return self.fileCount
def data(self, index, role=Qt.DisplayRole):
if not index.isValid():
return None
if index.row() >= len(self.fileList) or index.row() < 0:
return None
if role == Qt.DisplayRole:
return self.fileList[index.row()]
if role == Qt.BackgroundRole:
batch = (index.row() // 100) % 2
if batch == 0:
return QApplication.palette().base()
return QApplication.palette().alternateBase()
return None
def canFetchMore(self, index):
return self.fileCount < len(self.fileList)
def fetchMore(self, index):
remainder = len(self.fileList) - self.fileCount
itemsToFetch = min(100, remainder)
self.beginInsertRows(QModelIndex(), self.fileCount,
self.fileCount + itemsToFetch)
self.fileCount += itemsToFetch
self.endInsertRows()
self.numberPopulated.emit(itemsToFetch)
def setDirPath(self, path):
dir = QDir(path)
self.beginResetModel()
self.fileList = dir.entryList()
self.fileCount = 0
self.endResetModel()
class Window(QWidget):
def __init__(self, parent=None):
super(Window, self).__init__(parent)
model = FileListModel(self)
model.setDirPath(QLibraryInfo.location(QLibraryInfo.PrefixPath))
label = QLabel("Directory")
lineEdit = QLineEdit()
label.setBuddy(lineEdit)
view = QListView()
view.setModel(model)
self.logViewer = QTextBrowser()
self.logViewer.setSizePolicy(QSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred))
lineEdit.textChanged.connect(model.setDirPath)
lineEdit.textChanged.connect(self.logViewer.clear)
model.numberPopulated.connect(self.updateLog)
layout = QGridLayout()
layout.addWidget(label, 0, 0)
layout.addWidget(lineEdit, 0, 1)
layout.addWidget(view, 1, 0, 1, 2)
layout.addWidget(self.logViewer, 2, 0, 1, 2)
self.setLayout(layout)
self.setWindowTitle("Fetch More Example")
def updateLog(self, number):
self.logViewer.append("%d items added." % number)
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
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