python - 如何在使用自定义 QAbstractTableModel 创建 Qtableview 后为单元格着色

Question

我基于 QAbstractTableModel 创建了一个类“pandasModel”，如下所示:

import sys
from PyQt5.QtGui     import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore    import *
class pandasModel(QAbstractItemModel):

    def __init__(self, data, parent=None):
        QAbstractItemModel.__init__(self, parent)
        self._data = data

    def rowCount(self, parent=None):
        return self._data.index.size

    def columnCount(self, parent=None):
        return self._data.columns.size

    def data(self, index, role=Qt.DisplayRole):
        if index.isValid():
            if role == Qt.DisplayRole:
                return str(self._data.iloc[index.row(), index.column()])
            if role == Qt.EditRole:
                return str(self._data.iloc[index.row(), index.column()])
        return None

    def headerData(self, rowcol, orientation, role):
        if orientation == Qt.Horizontal and role == Qt.DisplayRole:
            return self._data.columns[rowcol]
        if orientation == Qt.Vertical and role == Qt.DisplayRole:
            return self._data.index[rowcol]
        return None

    def flags(self, index):
        flags = super(self.__class__, self).flags(index)
        flags |= Qt.ItemIsEditable
        flags |= Qt.ItemIsSelectable
        flags |= Qt.ItemIsEnabled
        flags |= Qt.ItemIsDragEnabled
        flags |= Qt.ItemIsDropEnabled
        return flags

    def sort(self, Ncol, order):
        """Sort table by given column number.
        """
        try:
            self.layoutAboutToBeChanged.emit()
            self._data = self._data.sort_values(self._data.columns[Ncol], ascending=not order)
            self.layoutChanged.emit()
        except Exception as e:
            print(e)

我还创建了一个 QTableView 来显示模型，如下所示:

class TableWin(QWidget):
    pos_updown = -1
    pos_save = []

    def __init__(self):
        super(TableWin, self).__init__()
        self.resize(200, 100)
        self.table = QTableView(self)
        self.v_layout = QVBoxLayout()
        self.v_layout.addWidget(self.table)
        self.setLayout(self.v_layout)
        self.showdata()

    def showdata(self):
        data = pd.DataFrame([[1,2,3,4],[5,6,7,8]])
        model = pandasModel(data)
        self.table.setModel(model)

    def set_cell_color(self, row, column)
        '''
          Pass two arguments to this function, which is called to set
          the background color of the cell corresponding to the row and column
        '''
if __name__ == '__main__':
    app = QApplication(sys.argv)
    tableView = TableWin()
    # I want to change cell's color by call function 'set_cell_color' here
    # tableView.set_cell_color(row=1,column=1) 
    tableView.show()
    sys.exit(app.exec_())

我们现在可以在 QTableview 中显示数据，但问题是我如何调用函数 'set_cell_color' 来设置具有给定行和列的单元格的背景颜色，所以你能告诉我如何完成 def set_cell_color 中的代码吗？

一旦我想像 QStandardItemModel 一样使用'model.item(row, col).setBackground(QColor(240, 255, 240))' 设置单元格的颜色，但引发错误''model' has no attribute 'item ''

this link shows a method to set cell's color

代码如下:

import sys
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *


class Model(QAbstractTableModel):
    def __init__(self, parent=None):
        super(Model, self).__init__(parent)
        self._data = [[['%d - %d' % (i, j), False] for j in range(10)] for i in range(10)]

    def rowCount(self, parent):
        return len(self._data)

    def columnCount(self, parent):
        return len(self._data[0])

    def flags(self, index):
        return Qt.ItemIsSelectable | Qt.ItemIsEnabled | Qt.ItemIsEditable

    def data(self, index, role):
        if index.isValid():
            data, changed = self._data[index.row()][index.column()]

        if role in [Qt.DisplayRole, Qt.EditRole]:
            return data

        if role == Qt.BackgroundRole and data == "In error":        # <---------
            return QBrush(Qt.red) 

    def setData(self, index, value, role):
        if role == Qt.EditRole:
            self._data[index.row()][index.column()] = [value, True]
            self.dataChanged.emit(index, index)
            return True
        return False

if __name__ == '__main__':
    app = QApplication(sys.argv)
    tableView = QTableView()
    m = Model(tableView)
    tableView.setModel(m)
    tableView.show()
    sys.exit(app.exec_())

在'data'函数中使用'return QBrush(Qt.red)'可以设置值为'In error'的单元格的背景颜色，但是当Qtableview完成创建时背景颜色已经设置，我只是想在调用函数 'set_cell_color' 时设置单元格的背景颜色，这意味着即使在 Qtableview 已经创建之后我也可以控制单元格的背景，我将非常感谢您的帮助。

Answer 1

逻辑是在模型中保存关联项目位置和项目颜色的信息，并更新它，必须发出 dataChanged 信号。

_{注意:您的模型是表类型，因此您必须继承自 QAbstractTableModel 而不是 QAbstractItemModel}

综合以上，解决方案是:

class pandasModel(QAbstractTableModel):
    def __init__(self, data, parent=None):
        QAbstractItemModel.__init__(self, parent)
        self._data = data

        self.colors = dict()

    def rowCount(self, parent=None):
        return self._data.index.size

    def columnCount(self, parent=None):
        return self._data.columns.size

    def data(self, index, role=Qt.DisplayRole):
        if index.isValid():
            if role == Qt.DisplayRole:
                return str(self._data.iloc[index.row(), index.column()])
            if role == Qt.EditRole:
                return str(self._data.iloc[index.row(), index.column()])
            if role == Qt.BackgroundRole:
                color = self.colors.get((index.row(), index.column()))
                if color is not None:
                    return color
        return None

    def headerData(self, rowcol, orientation, role):
        if orientation == Qt.Horizontal and role == Qt.DisplayRole:
            return self._data.columns[rowcol]
        if orientation == Qt.Vertical and role == Qt.DisplayRole:
            return self._data.index[rowcol]
        return None

    def flags(self, index):
        flags = super(self.__class__, self).flags(index)
        flags |= Qt.ItemIsEditable
        flags |= Qt.ItemIsSelectable
        flags |= Qt.ItemIsEnabled
        flags |= Qt.ItemIsDragEnabled
        flags |= Qt.ItemIsDropEnabled
        return flags

    def sort(self, Ncol, order):
        """Sort table by given column number.
        """
        try:
            self.layoutAboutToBeChanged.emit()
            self._data = self._data.sort_values(
                self._data.columns[Ncol], ascending=not order
            )
            self.layoutChanged.emit()
        except Exception as e:
            print(e)

    def change_color(self, row, column, color):
        ix = self.index(row, column)
        self.colors[(row, column)] = color
        self.dataChanged.emit(ix, ix, (Qt.BackgroundRole,))


class TableWin(QWidget):
    pos_updown = -1
    pos_save = []

    def __init__(self):
        super(TableWin, self).__init__()
        self.resize(200, 100)
        self.table = QTableView(self)
        self.v_layout = QVBoxLayout()
        self.v_layout.addWidget(self.table)
        self.setLayout(self.v_layout)
        self.showdata()

    def showdata(self):
        data = pd.DataFrame([[1, 2, 3, 4], [5, 6, 7, 8]])
        self.model = pandasModel(data)
        self.table.setModel(self.model)

    def set_cell_color(self, row, column):
        self.model.change_color(row, column, QBrush(Qt.red))