QAbstractTabelModel.data() 总是得到 index.row() == 0 并且只显示 1 行

Question

我已经在 python 中定义了我的自定义QAbstrtactTableModel 并实现了columnCount()、rowCount()、data() 和headerData()，并且还在add() 新条目中添加了一个函数：

import sys
from PySide2.QtUiTools import QUiLoader
from PySide2.QtWidgets import QApplication, QMainWindow
from PySide2.QtCore import QFile, QProcess, Signal,\
    Slot, QObject, QThread, Qt, QAbstractTableModel, QModelIndex,\
    QTimer
import random


class TableModel(QAbstractTableModel):
    def __init__(self, values):
        QAbstractTableModel.__init__(self)

        self.values = values

    def columnCount(self, parent=QModelIndex()):
        return 2

    def rowCount(self, parent=QModelIndex()):
        return len(self.values)

    def data(self, index, role=Qt.DisplayRole):
        print("called")
        if 0 <= index.row() < self.rowCount() and 0 <= index.column() < self.columnCount():
            if role == Qt.DisplayRole:
                print(index.row())
                if index.column() == 0:
                    return list(self.values.keys())[index.row()]
                else:
                    return self.values[list(self.values.keys())[index.row()]]

    def add(self, data):
        self.values[data[0]] = data[1]

    def headerData(self, section, orientation, role=Qt.DisplayRole):
        if role == Qt.DisplayRole:
            if orientation == Qt.Horizontal:
                if section == 0:
                    return "Parking,Meter"
                elif section == 1:
                    return "Revenue"


class Monitor(QObject):
    data_batch_ready = Signal(list)

    def __init__(self, parent=None):
        super(Monitor, self).__init__(parent)

    @Slot(list)
    def fill_batch(self):
        my_data = []
        for parking in range(4):
            for index in range(10):

                my_data.append([str(parking)+","+str(index), random.randint(1,101)])
        self.data_batch_ready.emit(my_data)


class Gui(QMainWindow):
    system_process = QProcess()
    parking_model = TableModel(values={"0,0": "0"})

    def __init__(self, parent=None):
        super(Gui, self).__init__(parent)
        file = QFile("minimal.ui")
        file.open(QFile.ReadOnly)

        loader = QUiLoader()
        ui = loader.load(file)
        self.setCentralWidget(ui)

        self.centralWidget().parking_table.setModel(self.parking_model)

    @Slot(list)
    def update_gui_revenue(self, data):
        print("fire")
        for row in data:
            self.parking_model.add(row)


def main():

    app = QApplication(sys.argv)
    gui = Gui()
    gui.show()

    thread = QThread()
    moni = Monitor()
    timer = QTimer(moni)
    timer.setInterval(1)
    moni.moveToThread(thread)
    moni.data_batch_ready.connect(gui.update_gui_revenue, Qt.QueuedConnection)
    timer.timeout.connect(moni.fill_batch, Qt.QueuedConnection)
    thread.started.connect(timer.start)
    thread.started.connect(lambda: print("time started"))
    thread.start()

    sys.exit(app.exec_())


if __name__ == "__main__":
    main()

数据是一个 python 字典，它通过调用一个随机函数来修改，该函数每 1 秒用 1 个条目填充字典，如下所示：

"0,0":[随机值]
"0,1":[随机值]
"0,2":[随机值]
"1,0":[随机值]
"1,1":[随机值]
"1,2":[随机值]

rowCount()正确反映了数据values中的行数，但tableView一直只显示1行，data()只是请求index.row() == 0

编辑：添加timer.setInterval(1)

Answer 1

如果您不通知，模型无法监控数据何时被修改，在您的情况下，有两种类型的修改，第一种是行插入，另一种是更新。对于插入行，您必须使用beginInsertRows() 和endInsertRows() 方法，第二次您必须通过启动dataChanged 信号来通知。

另一方面，不要在类中使模型变量，您必须使其成为实例的变量。

import sys
from PySide2 import QtCore, QtWidgets, QtUiTools
import random


class TableModel(QtCore.QAbstractTableModel):
    def __init__(self, values={}, parent=None):
        super(TableModel, self).__init__(parent)
        self.values = values

    def columnCount(self, parent=QtCore.QModelIndex()):
        if parent.isValid(): return 0
        return 2

    def rowCount(self, parent=QtCore.QModelIndex()):
        if parent.isValid(): return 0
        return len(self.values)

    def data(self, index, role=QtCore.Qt.DisplayRole):
        if 0 <= index.row() < self.rowCount() and 0 <= index.column() < self.columnCount():
            if role == QtCore.Qt.DisplayRole:
                if index.column() == 0:
                    return list(self.values.keys())[index.row()]
                else:
                    return self.values[list(self.values.keys())[index.row()]]

    def add(self, data):
        key, value = data 
        if key in self.values:
            row = list(self.values.keys()).index(key)
            self.values[key] = value
            self.dataChanged.emit(self.index(row, 1), self.index(row, 1))
        else:
            self.add_row(key, value)

    def add_row(self, key, value):
        self.beginInsertRows(QtCore.QModelIndex(), self.rowCount(), self.rowCount())
        self.values[key] = value
        self.endInsertRows()

    def headerData(self, section, orientation, role=QtCore.Qt.DisplayRole):
        if role == QtCore.Qt.DisplayRole:
            if orientation == QtCore.Qt.Horizontal:
                if section == 0:
                    return "Parking,Meter"
                elif section == 1:
                    return "Revenue"


class Monitor(QtCore.QObject):
    data_batch_ready = QtCore.Signal(list)

    @QtCore.Slot(list)
    def fill_batch(self):
        my_data = []
        for parking in range(4):
            for index in range(10):
                my_data.append([str(parking)+","+str(index), random.randint(1,101)])
        self.data_batch_ready.emit(my_data)


class Gui(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        super(Gui, self).__init__(parent)
        file =QtCore.QFile("minimal.ui")
        file.open(QtCore.QFile.ReadOnly)
        self.parking_model = TableModel(values={"0,0": "0"}, parent=self)

        loader = QtUiTools.QUiLoader()
        ui = loader.load(file)
        self.setCentralWidget(ui)

        self.centralWidget().parking_table.setModel(self.parking_model)

    @QtCore.Slot(list)
    def update_gui_revenue(self, data):
        for row in data:
            self.parking_model.add(row)


def main():

    app = QtWidgets.QApplication(sys.argv)
    gui = Gui()
    gui.show()

    thread = QtCore.QThread()
    moni = Monitor()
    timer = QtCore.QTimer(moni)
    timer.setInterval(10)
    moni.moveToThread(thread)
    moni.data_batch_ready.connect(gui.update_gui_revenue, QtCore.Qt.QueuedConnection)
    timer.timeout.connect(moni.fill_batch, QtCore.Qt.QueuedConnection)
    thread.started.connect(timer.start)
    thread.started.connect(lambda: print("time started"))
    thread.start()
    app.aboutToQuit.connect(thread.quit)
    sys.exit(app.exec_())


if __name__ == "__main__":
    main()