问题
I have a problem with the line below self.tableView.set??????????(df) that supposed to display the data frame in PyQt5. I put ??? there where I am missing the code I need.
def btn_clk(self):
path = self.lineEdit.text()
df = pd.read_csv(path)
self.tableView.set??????????(df)
The rest of the code works, because if I use print(df) in the above code, the data frame is printed in the IPython console. So, Pandas reads the CSV and prints it.
But, I tried many things to get it displayed in PyQt5 and nothing works. I am not very familiar with PyQt, just started to play around with it and I am stuck here.
Here is my code:
from PyQt5 import QtCore, QtGui, QtWidgets
import pandas as pd
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(662, 512)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.horizontalLayout = QtWidgets.QHBoxLayout(self.centralwidget)
self.horizontalLayout.setObjectName("horizontalLayout")
self.verticalLayout = QtWidgets.QVBoxLayout()
self.verticalLayout.setObjectName("verticalLayout")
self.lineEdit = QtWidgets.QLineEdit(self.centralwidget)
self.lineEdit.setObjectName("lineEdit")
self.verticalLayout.addWidget(self.lineEdit)
self.tableView = QtWidgets.QTableView(self.centralwidget)
self.tableView.setObjectName("tableView")
self.verticalLayout.addWidget(self.tableView)
self.pushButton = QtWidgets.QPushButton(self.centralwidget)
self.pushButton.setObjectName("pushButton")
self.verticalLayout.addWidget(self.pushButton)
self.horizontalLayout.addLayout(self.verticalLayout)
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 662, 21))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.pushButton.setText(_translate("MainWindow", "PushButton"))
self.pushButton.clicked.connect(self.btn_clk)
MainWindow.show()
def btn_clk(self):
path = self.lineEdit.text()
df = pd.read_csv(path)
self.tableView.set????????????(df)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)
MainWindow.show()
sys.exit(app.exec_())
回答1:
In the case of QTableView the data must be provided through a model since it implements the MVC (Model-View-Controller) paradigm, in the case of pandas there is no default model but we can create a custom as shown in the following part:
class PandasModel(QtCore.QAbstractTableModel):
def __init__(self, df = pd.DataFrame(), parent=None):
QtCore.QAbstractTableModel.__init__(self, parent=parent)
self._df = df.copy()
def toDataFrame(self):
return self._df.copy()
def headerData(self, section, orientation, role=QtCore.Qt.DisplayRole):
if role != QtCore.Qt.DisplayRole:
return QtCore.QVariant()
if orientation == QtCore.Qt.Horizontal:
try:
return self._df.columns.tolist()[section]
except (IndexError, ):
return QtCore.QVariant()
elif orientation == QtCore.Qt.Vertical:
try:
# return self.df.index.tolist()
return self._df.index.tolist()[section]
except (IndexError, ):
return QtCore.QVariant()
def data(self, index, role=QtCore.Qt.DisplayRole):
if role != QtCore.Qt.DisplayRole:
return QtCore.QVariant()
if not index.isValid():
return QtCore.QVariant()
return QtCore.QVariant(str(self._df.ix[index.row(), index.column()]))
def setData(self, index, value, role):
row = self._df.index[index.row()]
col = self._df.columns[index.column()]
if hasattr(value, 'toPyObject'):
# PyQt4 gets a QVariant
value = value.toPyObject()
else:
# PySide gets an unicode
dtype = self._df[col].dtype
if dtype != object:
value = None if value == '' else dtype.type(value)
self._df.set_value(row, col, value)
return True
def rowCount(self, parent=QtCore.QModelIndex()):
return len(self._df.index)
def columnCount(self, parent=QtCore.QModelIndex()):
return len(self._df.columns)
def sort(self, column, order):
colname = self._df.columns.tolist()[column]
self.layoutAboutToBeChanged.emit()
self._df.sort_values(colname, ascending= order == QtCore.Qt.AscendingOrder, inplace=True)
self._df.reset_index(inplace=True, drop=True)
self.layoutChanged.emit()
And then use it:
def btn_clk(self):
path = self.lineEdit.text()
df = pd.read_csv(path)
model = PandasModel(df)
self.tableView.setModel(model)
The complete code is here
Update 03-07-2019:
Some Pandas methods are deprecated so I have implemented a new version (which can also be used in QML as this answer shows):
class DataFrameModel(QtCore.QAbstractTableModel):
DtypeRole = QtCore.Qt.UserRole + 1000
ValueRole = QtCore.Qt.UserRole + 1001
def __init__(self, df=pd.DataFrame(), parent=None):
super(DataFrameModel, self).__init__(parent)
self._dataframe = df
def setDataFrame(self, dataframe):
self.beginResetModel()
self._dataframe = dataframe.copy()
self.endResetModel()
def dataFrame(self):
return self._dataframe
dataFrame = QtCore.pyqtProperty(pd.DataFrame, fget=dataFrame, fset=setDataFrame)
@QtCore.pyqtSlot(int, QtCore.Qt.Orientation, result=str)
def headerData(self, section: int, orientation: QtCore.Qt.Orientation, role: int = QtCore.Qt.DisplayRole):
if role == QtCore.Qt.DisplayRole:
if orientation == QtCore.Qt.Horizontal:
return self._dataframe.columns[section]
else:
return str(self._dataframe.index[section])
return QtCore.QVariant()
def rowCount(self, parent=QtCore.QModelIndex()):
if parent.isValid():
return 0
return len(self._dataframe.index)
def columnCount(self, parent=QtCore.QModelIndex()):
if parent.isValid():
return 0
return self._dataframe.columns.size
def data(self, index, role=QtCore.Qt.DisplayRole):
if not index.isValid() or not (0 <= index.row() < self.rowCount() \
and 0 <= index.column() < self.columnCount()):
return QtCore.QVariant()
row = self._dataframe.index[index.row()]
col = self._dataframe.columns[index.column()]
dt = self._dataframe[col].dtype
val = self._dataframe.iloc[row][col]
if role == QtCore.Qt.DisplayRole:
return str(val)
elif role == DataFrameModel.ValueRole:
return val
if role == DataFrameModel.DtypeRole:
return dt
return QtCore.QVariant()
def roleNames(self):
roles = {
QtCore.Qt.DisplayRole: b'display',
DataFrameModel.DtypeRole: b'dtype',
DataFrameModel.ValueRole: b'value'
}
return roles
回答2:
To fix the sorting...
from natsort import natsorted, index_natsorted, order_by_index
def sort(self, column, order):
self.layoutAboutToBeChanged.emit()
if order == 0:
self._df = self._df.reindex(index=order_by_index(self._df.index, index_natsorted(eval('self._df.%s' % (list(self._df.columns)[column])))))
else:
self._df = self._df.reindex(index=order_by_index(self._df.index, reversed(index_natsorted(eval('self._df.%s' % (list(self._df.columns)[column]))))))
self._df.reset_index(inplace=True, drop=True)
self.setDataFrame(self._df)
self.layoutChanged.emit()
来源：https://stackoverflow.com/questions/44603119/how-to-display-a-pandas-data-frame-with-pyqt5-pyside2