【Qt 教程】自定义排序 Custom Sorting in Qt

原文链接：https://www.xingyulei.com/post/qt-sorting/

Sorting Overview

Sorting happens a lot in qt viewports like list, table and tree. Using
convenience class such as item-based widget provides limited sorting options.

One common thing may occur when you are sorting items is the widget treats their
value as string instead of int, which will result incorrect ordering

list = ["3", "1", "2", "20", "92", "89", "40", "10", "11"]

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    mywidget = QtWidgets.QTableWidget()
    mywidget.insertColumn(0)

    for index in range(len(list)):
        mywidget.insertRow(index)
        value = list[index]
        item = QtWidgets.QTableWidgetItem(value)
        mywidget.setItem(index, 0, item)

    mywidget.sortItems(0, QtCore.Qt.AscendingOrder)
    mywidget.show()
    sys.exit(app.exec_())

This will sort the list of items based on their string, so the order will be:

- 1
- 10
- 11
- 2

instead of

- 1
- 2
- ...

So naturally, you would need to specify the item value as integer type,
but you cannot instantiate item with integer, but setData() will work

# intead of 
item = QtWidgets.QTableWidgetItem(int(value))
# do this
item.setData(QtCore.Qt.ItemDataRole, int(value))

Now everything will sort by numeric order

Custom Sorting (Operator override)

What if you need more than numeric value for your data, for example, when displaying frame number, you would like to include frame range
too. Like frame 1, frame 2, frame 3-7, frame 8, frame 9-14. It looks like using string
is the only option.

This time you need to override value compare operator for these value, that is making
your own item class like the following example

the __lt__ is the less than operator (<)

Everything should behave correctly

Custom Sorting (QSortFilterProxyModel Class)

https://doc-snapshots.qt.io/qtforpython-5.15/PySide2/QtCore/QSortFilterProxyModel.html

Reference

Stack Overflow - Is it possible to sort numbers in a QTreeWidget column?

标签：__,Sorting,Qt,自定义,frame,list,value,item,mywidget
来源： https://blog.csdn.net/sheldonlei/article/details/123203187