python - 如何根据原始列表相同的值但不同的索引创建新列表

Question

我在 Python 中使用Pyqt5创建了一个 GUI 界面，它导入一个 Excel 文件并将其列显示为listWidget中的项目。用户可以在其中检查项目，每个检查的项目都附加到new_list。

问题是，如果我有以下示例：

original_list = ["a","b","c","d","e","f"]

如果用户为新列表选择以下项目：

“C”、“f”、“a”

结果：

new_list = ["a","c","f"]

预期结果：

new_list =  ["c","f","a"]

在此图像中，用户在索引 0 的项目之前选择索引 3 的项目：

但是new_list将索引 0 的项目附加到索引 3 的项目之前

代码：

from PyQt5 import QtCore, QtGui, QtWidgets

import os
import pandas as pd
import numpy as np

import chardet




class Ui_MainWindow(QtWidgets.QMainWindow):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)

        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        
        self.header_list = QtWidgets.QListWidget(self.centralwidget)
        self.header_list.setMaximumSize(QtCore.QSize(120, 1667))
        self.header_list.setSelectionMode(QtWidgets.QAbstractItemView.MultiSelection)
        self.header_list.setObjectName("header_list")
        self.header_list.itemChanged.connect(self.selectionChanged)
        
        MainWindow.setCentralWidget(self.centralwidget)
        
        self.menubar = QtWidgets.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 22))
        self.menubar.setObjectName("menubar")

        self.menufile = self.menubar.addMenu("File")
        self.menufile.setObjectName("menufile")

        self.menuimportfile = QtWidgets.QAction("Import File",self.menufile)
        self.menuimportfile.setObjectName("importfile")
        self.menuimportfile.triggered.connect(lambda:self.loadFile())
        
        MainWindow.setMenuBar(self.menubar)
        
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        
        MainWindow.setStatusBar(self.statusbar)
        
        self.menufile.addAction(self.menuimportfile)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.menufile.setTitle(_translate("MainWindow", "file"))


    def loadFile(self):
        try:
            fileName, _ = QtWidgets.QFileDialog.getOpenFileName(self, "Open File", "", "Excel Files (*.csv *.xls *.xlsx)");
            print(fileName)            
            name, ext = os.path.splitext(fileName)
            print("name: {} ".format(name))
            print("ext:  {} ".format(ext))
            if ext == ".csv":
                with open(fileName, 'rb') as rawdata:
                    result = chardet.detect(rawdata.read(100000))
                print(result)
                df = pd.read_csv(fileName,encoding = result["encoding"])
            elif ext == ".xls" or ext == ".xlsx":
                df = pd.read_excel(fileName)
            self.df = df

            
        #part that display items in the qlistWidget
            self.header_list.clear()
            savelist = list(self.df)
            for item in savelist:
                qitem = QtWidgets.QListWidgetItem ( ) 
                qitem.setText ( item ) 
                qitem. setFlags ( QtCore. Qt . ItemIsUserCheckable | QtCore. Qt . ItemIsEnabled ) 
                qitem.setCheckState ( QtCore.Qt.Unchecked ) 
                self.header_list.addItem ( qitem )
        
        except Exception as e:
            print("error is {}".format(e))

    def selectionChanged(self):
        self.checked = []
        
        for row in range(self.header_list.count()):
            item = self.header_list.item(row)
            #need to be checked in order to display the item in the order that the user choose.
            if item.checkState():
                if item in self.checked:
                    del self.checked[item]
                else:
                # if not item in self.checked: 
                    self.checked.append(item)
            
                
        # checked.insert(len(checked)-1,item)
        print("Checked items: ", ", ".join(i.text() for i in self.checked))
        self.checked = [i.text() for i in self.checked]




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_())

标签： pythonlistpyqt5qlistwidget

Answer 1

看起来selectionChanged可以是下面的行。
只需迭代并收集选中的项目。

def selectionChanged(self):
    self.checked = [self.header_list.item(row) for row in range(self.header_list.count()) if self.header_list.item(row).checkState()]