python - TableView 中的行数意外影响交替行颜色

Question

我有一个带有 TableView 的 PySide2 Qt 5.13.1 应用程序。根据表中的行数，我遇到了一些奇怪的行为。我正在尝试交替行颜色。当行数为偶数时，剥离将按预期进行。当行数为奇数时，我的 TableView 会出现棋盘图案，这是意外的。下面的两个屏幕截图之间的唯一区别是模型中的行数。

main.py

import sys

from PySide2.QtCore import QUrl
from PySide2.QtQml import QQmlApplicationEngine, qmlRegisterType
from PySide2.QtWidgets import QApplication

from table_model import TableModel

import qml_rc  # noqa: F401


if __name__ == "__main__":
    app = QApplication(sys.argv)

    engine = QQmlApplicationEngine()

    qmlRegisterType(TableModel, "TableModel", 1, 0, "TableModel")

    engine.load(QUrl("qrc:/main.qml"))

    if not engine.rootObjects():
        sys.exit(-1)

    sys.exit(app.exec_())

main.qml

import QtQuick 2.13
import QtQuick.Controls 2.13

import TableModel 1.0

ApplicationWindow {
    visible: true

    Component.onCompleted: {
        showMaximized()
    }

    width: 640
    height: 480

    TableView {
        id: tableView
        clip: true
        anchors.fill: parent
        model: TableModel {}
        topMargin: columnsHeader.implicitHeight

        columnWidthProvider: function (column) { 
            return tableView.model ? tableView.width / tableView.model.columnCount() : 0
        }

        onWidthChanged: tableView.forceLayout()

        delegate: Rectangle {
            implicitWidth: tableView.columnWidthProvider(column)
            implicitHeight: 40
            color: index % 2 == 0 ? "grey" : "lightgrey"

            Text {
                text: display
            }
        }

        Row {
            id: columnsHeader
            y: tableView.contentY
            z: 2

            Repeater {
                model: tableView.columns > 0 ? tableView.columns : 1

                Rectangle {
                    width: tableView.columnWidthProvider(modelData)
                    height: 60
                    clip: true

                    Label {
                        id: headerText
                        width: parent.width
                        horizontalAlignment: Text.AlignHCenter
                        verticalAlignment: Text.AlignVCenter
                        text: tableView.model.headerData(modelData, Qt.Horizontal)
                        elide: Text.ElideRight
                        clip: true
                    }
                }
            }
        }
    }
}

表模型.py

from typing import Any, Optional

from PySide2.QtCore import QAbstractTableModel, QModelIndex, QObject, Qt

from table import Table


class TableModel(QAbstractTableModel):
    def __init__(self, parent: QObject = None) -> None:
        super().__init__(parent)
        self._model_data = Table(
            ["This", "Is", "A", "Test", "Of", "Headers"],
            [
                ["A", 1, 2, "B", "C", "D"],
                ["E", 3, 4, "F", "G", "H"],
                ["I", 5, 6, "J", "K", "L"],
                ["M", 7, 8, "N", "O", "P"],
                ["A", 1, 2, "B", "C", "D"],
                ["E", 3, 4, "F", "G", "H"],
                ["I", 5, 6, "J", "K", "L"],
                ["M", 7, 8, "N", "O", "P"],
                ["A", 1, 2, "B", "C", "D"],
                ["E", 3, 4, "F", "G", "H"],
                ["I", 5, 6, "J", "K", "L"],
                # ["I", 5, 6, "J", "K", "L"],
            ])

    def rowCount(self, parent=QModelIndex()) -> int:
        return len(self._model_data.rows)

    def columnCount(self, parent=QModelIndex()) -> int:
        return len(self._model_data.headers)

    def data(self, index: QModelIndex, role=Qt.DisplayRole) -> Optional[Any]:
        if role != Qt.DisplayRole:
            return None

        if not self.checkIndex(index, QAbstractTableModel.CheckIndexOption.IndexIsValid):
            return None

        return self._model_data.rows[index.row()][index.column()]

    def headerData(self, section: int, orientation, role) -> Optional[str]:
        if role != Qt.DisplayRole:
            return None

        if section < 0 or section >= len(self._model_data.headers):
            return None

        return self._model_data.headers[section]

    def reset_with_data(self, model_data: Table) -> None:
        self.beginResetModel()
        self._model_data = model_data
        self.endResetModel()

表.py

from dataclasses import dataclass
from typing import Any, List


@dataclass
class Table:
    headers: List[str]
    rows: List[List[Any]]

qml.qrc

<RCC>
    <qresource prefix="/">
        <file>main.qml</file>
    </qresource>
</RCC>

运行:

pipenv run pyside2-rcc -o qml_rc.py qml.qrc
pipenv run python main.py

Answer 1

index 属性并不代表行号，而是:

index = row + column * total_number_of_rows

而是使用row(或model.row)属性:

color: <b>model.row</b> % 2 == 0 ? "grey" : "lightgrey"