python - PyQt5 QTableWidget 单元格选择、保存和复制

Question

As extension to my previous question我添加了一个复制按钮。当用户在单元格中输入内容时，用户想要选择一行，然后单击复制按钮复制内容并在所选行下方添加具有相同内容的新行。下面的代码假设执行根据用户需要添加新行的工作，期望其内容不复制？我尝试打印来看看问题所在。我将 Qtablewidget 项目添加到空列表中，然后在 for 循环之前打印该列表，看到它已添加内容。应该如此，但是在 setItem 方法之后打印项目会返回空。它与表的序列化过程相同。我还想序列化整个表并将其粘贴回来。

列出 for 循环之前和之后的打印。

我的代码:

import sys
from PyQt5 import QtCore, QtGui, QtWidgets, Qt


class loadtable(QtWidgets.QTableWidget):
def __init__(self, parent=None):
    super(loadtable, self).__init__(1, 5,parent)



    self.setColumnCount(5)
    self.setRowCount(1)
    self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))   
    headertitle = ("A","B","C","D","E")
    QtWidgets.QTableWidgetItem(headertitle[i]))
    self.setHorizontalHeaderLabels(headertitle)
    self.verticalHeader().setVisible(False)
    self.horizontalHeader().setHighlightSections(False)
    self.horizontalHeader().setSectionResizeMode(QtWidgets.QHeaderView.Fixed)
    self.setSelectionMode(QtWidgets.QAbstractItemView.NoSelection)
    self.setColumnWidth(0, 130)
    combox_lay = QtWidgets.QComboBox(self)
    combox_lay.addItems(["I","II"])
    self.setCellWidget(0, 4, combox_lay)


    self.cellChanged.connect(self._cellclicked)


def _cellclicked(self):
    self.value = self.currentItem()
    self.value.setTextAlignment(Qt.AlignCenter)

@QtCore.pyqtSlot()  
def _addrow(self):
    rowcount = self.rowCount()
    print(rowcount)
    self.setRowCount(rowcount+1)
    combox_add = QtWidgets.QComboBox(self)
    combox_add.addItems(["I","II"])
    self.setCellWidget(rowcount, 4, combox_add)

@QtCore.pyqtSlot()
def _removerow(self):
    if self.rowCount() > 0:
        self.removeRow(self.rowCount()-1)

@QtCore.pyqtSlot()
def _cellselected(self):
    r = self.currentRow()
    c = self.columnCount()
    cell = []
    for i in range(c):
        if i == c-1:
            it = self.cellWidget(r , i)
        else:
            it = self.item(r , i)
        cell.append(it)
    self.setcopy(cell,r,c)

def setcopy(self,cell,r,c):
    self.insertRow(r+1)
    print(cell)
    for j in range(c):
        if j < c-1:
            it = self.setItem(r+1, j,cell[j])
        else:
            it = self.setCellWidget(r+1, j, cell[j])
        print(it)
    return it    

class thirdtabloads(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(thirdtabloads, self).__init__(parent)      
        table = loadtable()


    button_layout = QtWidgets.QVBoxLayout()
    add_button = QtWidgets.QPushButton("Add")
    add_button.clicked.connect(table._addrow)
    delete_button = QtWidgets.QPushButton("Delete")
    delete_button.clicked.connect(table._removerow)
    copy_button = QtWidgets.QPushButton("Copy")
    copy_button.clicked.connect(table._cellselected)

    button_layout = QtWidgets.QVBoxLayout()
    button_layout.addWidget(add_button, alignment=QtCore.Qt.AlignBottom)
    button_layout.addWidget(delete_button, alignment=QtCore.Qt.AlignTop)
    button_layout.addWidget(copy_button, alignment=QtCore.Qt.AlignTop)


    tablehbox = QtWidgets.QHBoxLayout()
    tablehbox.setContentsMargins(10,10,10,10)
    tablehbox.addWidget(table)

    grid = QtWidgets.QGridLayout(self)
    grid.addLayout(button_layout, 0, 1)
    grid.addLayout(tablehbox, 0, 0)        



if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = thirdtabloads()
    w.show()
    sys.exit(app.exec_())

Answer 1

首先，setItem()方法不会返回任何内容，因为它是一个setter，所以如果你想知道该项目是否存在，你必须使用作为 getter 的 item() 方法。

讨论这个问题，您已经注意到必须复制 2 个元素:QTableWidgetItem 和使用 setCellWidget() 设置的小部件。如果你想复制QTableWidgetItem，你必须使用它的clone()方法，对于小部件来说，没有方法可以做到这一点，所以你必须创建复制必要的方法，在我的解决方案中，我展示了如何从 QComboBox 复制项目，如果您有其他小部件，则必须实现更多代码。最后始终进行检查，例如，当未选择任何内容时，currentRow 可以为 -1。

import sys
from PyQt5 import QtCore, QtGui, QtWidgets

# copy qwidgets
def copy_widget(w):
    if isinstance(w, QtWidgets.QWidget):
        new_w = type(w)()
        if isinstance(w, QtWidgets.QComboBox):
            vals = [w.itemText(ix) for ix in range(w.count())]
            new_w.addItems(vals)

        # if instance(w, QtWidgets.AnotherWidget):
        #     copy values
        return new_w

class LoadTable(QtWidgets.QTableWidget):
    def __init__(self, parent=None):
        super(LoadTable, self).__init__(1, 5, parent)
        self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))   
        headertitle = ("A","B","C","D","E")
        self.setHorizontalHeaderLabels(headertitle)
        self.verticalHeader().hide()
        self.horizontalHeader().setHighlightSections(False)
        self.horizontalHeader().setSectionResizeMode(QtWidgets.QHeaderView.Fixed)

        self.setSelectionMode(QtWidgets.QAbstractItemView.NoSelection)
        self.setColumnWidth(0, 130)

        combox_lay = QtWidgets.QComboBox(self)
        combox_lay.addItems(["I","II"])
        self.setCellWidget(0, 4, combox_lay)

        self.cellChanged.connect(self._cellclicked)

    @QtCore.pyqtSlot(int, int)
    def _cellclicked(self, r, c):
        it = self.item(r, c)
        it.setTextAlignment(QtCore.Qt.AlignCenter)        

    @QtCore.pyqtSlot()
    def _addrow(self):
        rowcount = self.rowCount()
        self.insertRow(rowcount)
        combox_add = QtWidgets.QComboBox(self)
        combox_add.addItems(["I","II"])
        self.setCellWidget(rowcount, 4, combox_add)

    @QtCore.pyqtSlot()
    def _removerow(self):
        if self.rowCount() > 0:
            self.removeRow(self.rowCount()-1)

    @QtCore.pyqtSlot()
    def _copyrow(self):
        r = self.currentRow()
        if 0 <= r < self.rowCount():
            cells = {"items": [], "widgets": []}
            for i in range(self.columnCount()):
                it = self.item(r, i)
                if it:
                    cells["items"].append((i, it.clone()))
                w = self.cellWidget(r, i)
                if w:
                    cells["widgets"].append((i, copy_widget(w)))
            self.copy(cells, r+1)

    def copy(self, cells, r):
        self.insertRow(r)
        for i, it in cells["items"]:
            self.setItem(r, i, it)
        for i, w in cells["widgets"]:
            self.setCellWidget(r, i, w)


class ThirdTabLoads(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(ThirdTabLoads, self).__init__(parent)    

        table = LoadTable()

        add_button = QtWidgets.QPushButton("Add")
        add_button.clicked.connect(table._addrow)

        delete_button = QtWidgets.QPushButton("Delete")
        delete_button.clicked.connect(table._removerow)

        copy_button = QtWidgets.QPushButton("Copy")
        copy_button.clicked.connect(table._copyrow)

        button_layout = QtWidgets.QVBoxLayout()
        button_layout.addWidget(add_button, alignment=QtCore.Qt.AlignBottom)
        button_layout.addWidget(delete_button, alignment=QtCore.Qt.AlignTop)
        button_layout.addWidget(copy_button, alignment=QtCore.Qt.AlignTop)

        tablehbox = QtWidgets.QHBoxLayout()
        tablehbox.setContentsMargins(10, 10, 10, 10)
        tablehbox.addWidget(table)

        grid = QtWidgets.QGridLayout(self)
        grid.addLayout(button_layout, 0, 1)
        grid.addLayout(tablehbox, 0, 0)        


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = ThirdTabLoads()
    w.show()
    sys.exit(app.exec_())