1 files changed, 137 insertions, 0 deletions
diff --git a/examples/widgets/itemviews/fetchmore/fetchmore.py b/examples/widgets/itemviews/fetchmore/fetchmore.py
new file mode 100644
index 000000000..5150250e0
--- /dev/null
+++ b/examples/widgets/itemviews/fetchmore/fetchmore.py
@@ -0,0 +1,137 @@
+# Copyright (C) 2009 Darryl Wallace, 2009 <wallacdj@gmail.com>
+# Copyright (C) 2013 Riverbank Computing Limited.
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+"""PySide6 port of the itemviews/fetchmore/fetchmore example from Qt v6.x
+
+Navigate to a directory with many entries by doubleclicking and scroll
+down the list to see the model being populated on demand.
+"""
+
+import sys
+
+from PySide6.QtCore import (QAbstractListModel, QDir,
+                            QModelIndex, Qt, Signal, Slot)
+from PySide6.QtWidgets import (QApplication, QFileIconProvider, QListView,
+                               QPlainTextEdit, QSizePolicy, QVBoxLayout,
+                               QWidget)
+
+
+BATCH_SIZE = 100
+
+
+class FileListModel(QAbstractListModel):
+
+    number_populated = Signal(str, int, int, int)
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self._path = ''
+        self._file_count = 0
+        self._file_list = []
+        self._icon_provider = QFileIconProvider()
+
+    def rowCount(self, parent=QModelIndex()):
+        return self._file_count
+
+    def data(self, index, role=Qt.DisplayRole):
+        if not index.isValid():
+            return None
+
+        row = index.row()
+        if row >= len(self._file_list) or row < 0:
+            return None
+
+        if role == Qt.DisplayRole:
+            return self._file_list[row].fileName()
+
+        if role == Qt.BackgroundRole:
+            batch = row // BATCH_SIZE
+            palette = qApp.palette()  # noqa: F821
+            return palette.base() if batch % 2 == 0 else palette.alternateBase()
+
+        if role == Qt.DecorationRole:
+            return self._icon_provider.icon(self._file_list[row])
+
+        return None
+
+    def canFetchMore(self, index):
+        return self._file_count < len(self._file_list)
+
+    def fetchMore(self, index):
+        start = self._file_count
+        total = len(self._file_list)
+        remainder = total - start
+        items_to_fetch = min(BATCH_SIZE, remainder)
+
+        self.beginInsertRows(QModelIndex(), start, start + items_to_fetch)
+
+        self._file_count += items_to_fetch
+
+        self.endInsertRows()
+
+        self.number_populated.emit(self._path, start, items_to_fetch, total)
+
+    @Slot(str)
+    def set_dir_path(self, path):
+        self._path = path
+        directory = QDir(path)
+
+        self.beginResetModel()
+        directory_filter = QDir.AllEntries | QDir.NoDot
+        self._file_list = directory.entryInfoList(directory_filter, QDir.Name)
+        self._file_count = 0
+        self.endResetModel()
+
+    def fileinfo_at(self, index):
+        return self._file_list[index.row()]
+
+
+class Window(QWidget):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self._model = FileListModel(self)
+        self._model.set_dir_path(QDir.rootPath())
+
+        self._view = QListView()
+        self._view.setModel(self._model)
+
+        self._log_viewer = QPlainTextEdit()
+        self._log_viewer.setSizePolicy(QSizePolicy(QSizePolicy.Preferred,
+                                       QSizePolicy.Preferred))
+
+        self._model.number_populated.connect(self.update_log)
+        self._view.activated.connect(self.activated)
+
+        layout = QVBoxLayout(self)
+        layout.addWidget(self._view)
+        layout.addWidget(self._log_viewer)
+
+        self.setWindowTitle("Fetch More Example")
+
+    @Slot(str, int, int, int)
+    def update_log(self, path, start, number, total):
+        native_path = QDir.toNativeSeparators(path)
+        last = start + number - 1
+        entry = f'{start}..{last}/{total} items from "{native_path}" added.'
+        self._log_viewer.appendPlainText(entry)
+
+    @Slot(QModelIndex)
+    def activated(self, index):
+        fileinfo = self._model.fileinfo_at(index)
+        if fileinfo.isDir():
+            self._log_viewer.clear()
+            self._model.set_dir_path(fileinfo.absoluteFilePath())
+
+
+if __name__ == '__main__':
+    app = QApplication(sys.argv)
+
+    window = Window()
+    window.resize(400, 500)
+    window.show()
+
+    sys.exit(app.exec())