为单个单元格格式化 ForegroundRole

Question

我从QTableView refresh 获得了大部分代码。

我从 SQL 数据库中提取数据并通过 Pandas DataFrame 将其呈现给 QAbstractTableModel 并使用 QTableView 显示。一切正常（感谢上述文章的重大帮助）。现在的问题是我只想为第二列中的文本着色，这与我在数据函数的颜色决策中使用的列相同。

我已经调试了代码，发现“it”变量中的值只是我想要着色的值，所以在我看来，当“return qtg.QBrush(qtc.QT."COLOR" ) 应用它只会为该数据着色，而是为整行着色。

任何有助于理解这段代码如何工作的帮助将不胜感激！

import sys
import threading

import pandas as pd

from PyQt5 import QtCore as qtc
from PyQt5 import QtGui as qtg
from PyQt5 import QtWidgets as qtw

import data
import pyodbc


class PandasManager(qtc.QObject):
    dataFrameChanged = qtc.pyqtSignal(pd.DataFrame)

    def start(self):
        self.t = threading.Timer(0, self.load)
        self.t.start()

    def load(self):
        df = data.get_data()

        self.dataFrameChanged.emit(df)
        self.t = threading.Timer(5.0, self.load)
        self.t.start()

    def stop(self):
        self.t.cancel()


class PandasModel(qtc.QAbstractTableModel):
    def __init__(self, df=pd.DataFrame()):
        qtc.QAbstractTableModel.__init__(self)
        self._df = df

    @qtc.pyqtSlot(pd.DataFrame)
    def setDataFrame(self, df):
        self.beginResetModel()
        self._df = df
        self.endResetModel()

    def rowCount(self, parent=None):
        return self._df.shape[0]

    def columnCount(self, parent=None):
        return self._df.shape[1]

    def data(self, index, role=qtc.Qt.DisplayRole):
        if index.isValid():  #Checking the validity of the index
            if role == qtc.Qt.ForegroundRole: # The role for text color
                if self.columnCount() >= 3 : # checking the number of columns is greater than 3 (Should be 5)
                    it = self._df.iloc[index.row(), 1] # Finds the specific data (second column) to test and assigns it to the variable "it"
                    if it == "WE": # If the value matches
                        return qtg.QBrush(qtc.Qt.yellow) #Color -- I may not quite understand what this is actually doing
                    if it == "UMaint": # Another value to match
                        return qtg.QBrush(qtc.Qt.green) # Another color
            if role == qtc.Qt.DisplayRole: # If not ForegroundRole but is DisplayRole
                return str(self._df.iloc[index.row(), index.column()]) #Set value

    def headerData(self, col, orientation, role):
        if orientation == qtc.Qt.Horizontal and role == qtc.Qt.DisplayRole:
            return self._df.columns[col]
        return None


if __name__ == "__main__":
    app = qtw.QApplication(sys.argv)
    w = qtw.QTableView()
    model = PandasModel()
    w.setModel(model)
    w.show()

    manager = PandasManager()
    manager.dataFrameChanged.connect(model.setDataFrame)
    manager.start()

    ret = app.exec_()

    manager.stop()

    sys.exit(ret)

Answer 1

我能够让代码按我想要的方式工作，我将它粘贴在下面。我确信有一种更清洁、更“pythonic”的方式来完成它，但它确实有效。

至于是什么使它起作用，我不太确定。我确实为列索引实现了一个变量，以帮助我了解发生了什么，我删除了列计数 if 语句，但除此之外我不确定。

下面是我的工作代码，希望将来可以帮助其他人。

def data(self, index, role=QtCore.Qt.DisplayRole):

        current_column = index.column()
        current_row = index.row()

        we_color = QtGui.QColor('#FF9900')
        wp_color = QtGui.QColor('#CCCC33')
        umaint_color = QtGui.QColor('#FF0000')
        smaint_color = QtGui.QColor('#FA8072')
        equipinstall_color = QtGui.QColor('#0066FF')
        upartwt_color = QtGui.QColor('#990099')
        le_color = QtGui.QColor('#CC6600')
        prodrun_color = QtGui.QColor('#00FF00')
        matlassist_color = QtGui.QColor('#CC9999')
        oqual_color = QtGui.QColor('#C993FF')
        equipeng_color = QtGui.QColor('#B22222')

        white_color = QtGui.QColor(QtCore.Qt.white)
        black_color = QtGui.QColor(QtCore.Qt.black)

        if index.isValid():  # Checking the validity of the index
            if role == QtCore.Qt.ForegroundRole:  # The role for text color
                if current_column == 1:  # checking the number of columns is greater than 3 (Should be 5)
                    it = self._dataframe.iloc[index.row(), current_column]  # Finds the specific data (second column) to test and assigns it to the variable "it"
                    if it == "WE":  # If the value matches
                        return QtGui.QBrush(black_color)  # Color -- I may not quite understand what this is actually doing
                    if it == "WP":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "SMaint":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "UMaint":  # Another value to match
                        return QtGui.QBrush(white_color)  # Another color+
                    if it == "EquipInstall":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "UPartWt":  # Another value to match
                        return QtGui.QBrush(white_color)  # Another color+
                    if it == "LE":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "ProdRun":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "MatlAssist":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "OQual":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+
                    if it == "EquipEng":  # Another value to match
                        return QtGui.QBrush(black_color)  # Another color+

            if role == QtCore.Qt.BackgroundColorRole:  # The role for text color
                if current_column == 1:
                    it = self._dataframe.iloc[index.row(), current_column]  # Finds the specific data (second column) to test and assigns it to the variable "it"
                    if it == "WE":  # If the value matches
                        return QtGui.QBrush(we_color)  # Color -- I may not quite understand what this is actually doing
                    if it == "WP":  # Another value to match
                        return QtGui.QBrush(wp_color)  # Another color+
                    if it == "SMaint":  # Another value to match
                        return QtGui.QBrush(smaint_color)  # Another color+
                    if it == "UMaint":  # Another value to match
                        return QtGui.QBrush(umaint_color)  # Another color+
                    if it == "EquipInstall":  # Another value to match
                        return QtGui.QBrush(equipinstall_color)  # Another color+
                    if it == "UPartWt":  # Another value to match
                        return QtGui.QBrush(upartwt_color)  # Another color+
                    if it == "LE":  # Another value to match
                        return QtGui.QBrush(le_color)  # Another color+
                    if it == "ProdRun":  # Another value to match
                        return QtGui.QBrush(prodrun_color)  # Another color+
                    if it == "MatlAssist":  # Another value to match
                        return QtGui.QBrush(matlassist_color)  # Another color+
                    if it == "OQual":  # Another value to match
                        return QtGui.QBrush(oqual_color)  # Another color+
                    if it == "EquipEng":  # Another value to match
                        return QtGui.QBrush(equipeng_color)  # Another color+

            if role == QtCore.Qt.DisplayRole:  # If not ForegroundRole but is DisplayRole
                return str(self._dataframe.iloc[index.row(), index.column()])  # Set value