Question

以下示例应用程序旨在显示QTreeView，将其填充4行，并再添加12行，将其作为子级随机分布在最初添加的4行之间。必须通过其UUID列（不能是行的第一列）的值来选择父对象。所有的UUID都是唯一的。

我正在尝试使用self.findItems(parent_uuid, Qt.MatchExactly, 1)（其中parent_uuid: str是选定的父ID值，而1是存储ID的列的索引）来查找所需的父行，但返回了结果似乎只是包含UUID的QStandardItem的1元素列表。

如何更改代码以实现所需的行为？

我使用Python 3.7和Qt 5.11。 UI代码是使用pyuic5从QtDesigner生成的Qt UI XML文件生成的。

完整的应用程序源代码：

#!/usr/bin/env python


import random
import sys
import uuid

from PyQt5 import QtCore, QtWidgets
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QStandardItemModel, QStandardItem
from PyQt5.QtWidgets import QApplication, QMainWindow

LETTERS = 'abcdefghijklm'


def main():
    application = QApplication(sys.argv)
    main_window = MainWindow()
    main_window.show()
    sys.exit(application.exec_())


class TreeViewModel(QStandardItemModel):
    def __init__(self, *args, **kwargs):
        super(TreeViewModel, self).__init__(*args, **kwargs)

    def populate(self):  # This is where the work is done
        self.clear()
        self.setHorizontalHeaderLabels(['Name', 'UUID', 'Attr1'])

        parents_uuids = []

        for i in range(16):
            name = random.choice(LETTERS) \
                   + random.choice(LETTERS) \
                   + random.choice(LETTERS)
            uuid_ = str(uuid.uuid4())
            attr1 = str(random.random())

            row = [QStandardItem(name),
                   QStandardItem(uuid_),
                   QStandardItem(attr1)]

            if len(parents_uuids) < 4:
                self.appendRow(row)
                parents_uuids.append(uuid_)
            else:
                # TODO: Fix this else clause so it'd make the new row a child
                # The parent row must be found by its UUID column str value
                parent_uuid = random.choice(parents_uuids)
                parent = self.findItems(parent_uuid, Qt.MatchExactly, 1)
                parent.appendRow(row)  # Error


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        self.ui.actionPopulateTree.triggered \
            .connect(self.on_action_populate_tree)
        self.ui.treeView.setModel(TreeViewModel(self))

    def on_action_populate_tree(self):
        self.ui.treeView.model().populate()


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(320, 240)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.gridLayout = QtWidgets.QGridLayout(self.centralwidget)
        self.gridLayout.setObjectName("gridLayout")
        self.treeView = QtWidgets.QTreeView(self.centralwidget)
        self.treeView.setObjectName("treeView")
        self.gridLayout.addWidget(self.treeView, 0, 0, 1, 1)
        MainWindow.setCentralWidget(self.centralwidget)
        self.toolBar = QtWidgets.QToolBar(MainWindow)
        self.toolBar.setObjectName("toolBar")
        MainWindow.addToolBar(QtCore.Qt.TopToolBarArea, self.toolBar)
        self.actionPopulateTree = QtWidgets.QAction(MainWindow)
        self.actionPopulateTree.setObjectName("actionPopulateTree")
        self.toolBar.addAction(self.actionPopulateTree)

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

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.toolBar.setWindowTitle(_translate("MainWindow", "toolBar"))
        self.actionPopulateTree.setText(_translate("MainWindow", "PopulateTree"))


if __name__ == "__main__":
    main()

Answer 1

findItems返回与搜索匹配的项目的列表，因此，在您的情况下，您只需要获取第一个项目，但仍然不能添加这些项目，因为您必须将第0列中的项目作为父项，但是您已经获得了列1中的项目，因此其他逻辑部分将获得该项目：

parent_uuid = random.choice(parents_uuids)
items = self.findItems(parent_uuid, Qt.MatchExactly, 1)
if items:
    ix = self.indexFromItem(items[0])
    ix_col_0 = self.sibling(ix.row(), 0, ix)
    it_col_0 = self.itemFromIndex(ix_col_0)
    it_col_0.appendRow(row)

如何将子行添加到通过特定列值找到的QTreeView行中？

1 个答案: