具有复杂小部件表示的模型/视图 QListView

Question

我正在尝试在 PyQT5 应用程序中显示 QListView 以显示一些数据。

我的目标是用复杂的表示来表示这些数据，而不仅仅是一行文本。

因此，我的 QListView 应该“实例化”从 Ui 文件加载的新 QWidget，并使用该 Ui 表示显示每个元素。

我的问题在于我的 Windows 布局。

我有一个主窗口，其中有一个 QSplitter，QListView 位于左侧，右侧有一些小部件（Label、textedit、...） QMainWindow 设计器：

我想要表示为这个小部件的 QListView 的每一行： 小部件设计器：

似乎如果 QListView 在这样的小部件容器内：

Arbo 对象检查器：

然后我有一个奇怪的行为，其中子小部件显示在彼此之上：

ListView 小部件堆叠：

但是如果我删除 QListView 的容器 OkWindow 设计器：

和检查员的观点

它们显示正确

按预期工作：

知道为什么吗？

我的代码和在模型/视图 QListView 中实现复杂小部件表示的方式有什么问题吗？

这是应用示例的代码：

import typing

from PyQt5 import QtCore, uic
from PyQt5.QtCore import QAbstractListModel, QModelIndex, Qt
from PyQt5.QtWidgets import (
    QApplication,
    QStyledItemDelegate,
    QWidget, QMainWindow, )


class Editor(QWidget):
    def __init__(self, index, parent=None):
        super().__init__(parent)
        uic.loadUi('step.ui', self)

        value = index.model().data(index, Qt.ItemDataRole)

        self.label.setText(value)


class MyListModel(QAbstractListModel):
    def __init__(self, parent=None):
        super().__init__(parent)
        self._data_list = []

    def data(self, index: QModelIndex, role: int = Qt.DisplayRole) -> typing.Any:
        if role == Qt.ItemDataRole:
            return self._data_list[index.row()]

    def rowCount(self, parent: QModelIndex = QModelIndex()) -> int:
        return len(self._data_list)

    @property
    def data_list(self):
        return self._data_list

    @data_list.setter
    def data_list(self, data_list):
        self.beginResetModel()
        self._data_list = data_list.copy()
        self.endResetModel()


class StyledItemDelegate(QStyledItemDelegate):

    def __init__(self, parent):
        QStyledItemDelegate.__init__(self, parent)
        self.editor = None

    def createEditor(self, parent, option, index):
        self.editor = Editor(index, parent)
        return self.editor

    def sizeHint(self, option: 'QStyleOptionViewItem', index: QtCore.QModelIndex) -> QtCore.QSize:
        if self.editor:
            return self.editor.sizeHint()
        else:
            return super().sizeHint(option, index)

data = ["Apple", "Strawberry", "Cherry"]


class MainWindow(QMainWindow):
    def __init__(self, qapp):
        """
        Init main window
        """
        super().__init__()

        self.qapp = qapp
        # Not working main_window ui file 
        # uic.loadUi('main_window.ui', self)

        # Working main_window ui file 
        uic.loadUi('main_window_ok.ui', self)

        self.load_data()

    def load_data(self):
        controller = MyCtrl(self)
        controller.load_datalist()

class MyCtrl:
    def __init__(self, parent: QMainWindow):
        self.parent = parent

    def load_datalist(self):
        self.model = MyListModel()
        self.model.data_list = data
        self.parent.listView.setModel(self.model)
        delegate = StyledItemDelegate(self.parent.listView)
        self.parent.listView.setItemDelegate(delegate)

        for i in range(self.model.rowCount()):
            index = self.model.index(i, 0)
            self.parent.listView.openPersistentEditor(index)


if __name__ == "__main__":
    import sys

    app = QApplication(sys.argv)
    main = MainWindow(app)
    main.showMaximized()

    sys.exit(app.exec_())

main_window.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>800</width>
    <height>642</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QVBoxLayout" name="verticalLayout_3">
    <item>
     <widget class="QSplitter" name="splitter">
      <property name="orientation">
       <enum>Qt::Horizontal</enum>
      </property>
      <widget class="QWidget" name="widget" native="true">
       <layout class="QVBoxLayout" name="verticalLayout">
        <item>
         <widget class="QListView" name="listView"/>
        </item>
       </layout>
      </widget>
      <widget class="QWidget" name="widget_2" native="true">
       <layout class="QVBoxLayout" name="verticalLayout_2">
        <item>
         <widget class="QLabel" name="label">
          <property name="text">
           <string>TextLabel</string>
          </property>
         </widget>
        </item>
        <item>
         <widget class="QLineEdit" name="lineEdit"/>
        </item>
        <item>
         <widget class="QSlider" name="horizontalSlider">
          <property name="orientation">
           <enum>Qt::Horizontal</enum>
          </property>
         </widget>
        </item>
        <item>
         <spacer name="verticalSpacer">
          <property name="orientation">
           <enum>Qt::Vertical</enum>
          </property>
          <property name="sizeHint" stdset="0">
           <size>
            <width>20</width>
            <height>40</height>
           </size>
          </property>
         </spacer>
        </item>
       </layout>
      </widget>
     </widget>
    </item>
    <item>
     <layout class="QHBoxLayout" name="horizontalLayout">
      <item>
       <spacer name="horizontalSpacer">
        <property name="orientation">
         <enum>Qt::Horizontal</enum>
        </property>
        <property name="sizeHint" stdset="0">
         <size>
          <width>40</width>
          <height>20</height>
         </size>
        </property>
       </spacer>
      </item>
      <item>
       <widget class="QPushButton" name="pushButton_2">
        <property name="text">
         <string>Cancel</string>
        </property>
       </widget>
      </item>
      <item>
       <widget class="QPushButton" name="pushButton">
        <property name="text">
         <string>Ok</string>
        </property>
       </widget>
      </item>
     </layout>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>800</width>
     <height>26</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

main_window_ok.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>799</width>
    <height>642</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QVBoxLayout" name="verticalLayout_3">
    <item>
     <widget class="QSplitter" name="splitter">
      <property name="orientation">
       <enum>Qt::Horizontal</enum>
      </property>
      <widget class="QListView" name="listView"/>
      <widget class="QWidget" name="widget_2" native="true">
       <layout class="QVBoxLayout" name="verticalLayout_2">
        <item>
         <widget class="QLabel" name="label">
          <property name="text">
           <string>TextLabel</string>
          </property>
         </widget>
        </item>
        <item>
         <widget class="QLineEdit" name="lineEdit"/>
        </item>
        <item>
         <widget class="QSlider" name="horizontalSlider">
          <property name="orientation">
           <enum>Qt::Horizontal</enum>
          </property>
         </widget>
        </item>
        <item>
         <spacer name="verticalSpacer">
          <property name="orientation">
           <enum>Qt::Vertical</enum>
          </property>
          <property name="sizeHint" stdset="0">
           <size>
            <width>20</width>
            <height>40</height>
           </size>
          </property>
         </spacer>
        </item>
       </layout>
      </widget>
     </widget>
    </item>
    <item>
     <layout class="QHBoxLayout" name="horizontalLayout">
      <item>
       <spacer name="horizontalSpacer">
        <property name="orientation">
         <enum>Qt::Horizontal</enum>
        </property>
        <property name="sizeHint" stdset="0">
         <size>
          <width>40</width>
          <height>20</height>
         </size>
        </property>
       </spacer>
      </item>
      <item>
       <widget class="QPushButton" name="pushButton_2">
        <property name="text">
         <string>Cancel</string>
        </property>
       </widget>
      </item>
      <item>
       <widget class="QPushButton" name="pushButton">
        <property name="text">
         <string>Ok</string>
        </property>
       </widget>
      </item>
     </layout>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>799</width>
     <height>21</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

step.ui 文件

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Form</class>
 <widget class="QWidget" name="Form">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>387</width>
    <height>173</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Form</string>
  </property>
  <layout class="QVBoxLayout" name="verticalLayout">
   <item>
    <widget class="QLabel" name="label">
     <property name="text">
      <string>TextLabel</string>
     </property>
    </widget>
   </item>
   <item>
    <layout class="QHBoxLayout" name="horizontalLayout">
     <item>
      <widget class="QDial" name="dial"/>
     </item>
     <item>
      <widget class="QComboBox" name="comboBox"/>
     </item>
    </layout>
   </item>
  </layout>
 </widget>
 <resources/>
 <connections/>
</ui>

Answer 1

创建一个存储 QWidget 的变量是无用且危险的，因为例如您将只有最后一个小部件，或者更糟的是访问已删除的小部件。相反，您必须使用角色来存储和获取大小，并且默认角色是 Qt::SizeHintRole。

from PyQt5.uic import loadUi
from PyQt5.QtCore import QAbstractListModel, QModelIndex, Qt, QSize
from PyQt5.QtWidgets import (
    QApplication,
    QStyledItemDelegate,
    QWidget,
    QMainWindow,
)


class Editor(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        loadUi("step.ui", self)


class MyListModel(QAbstractListModel):
    def __init__(self, parent=None):
        super().__init__(parent)
        self._data_list = list()

        self._size_hints = dict()

    def rowCount(self, parent=QModelIndex()):
        if parent.isValid():
            return 0
        return len(self._data_list)

    def data(self, index, role=Qt.DisplayRole):
        if role == Qt.DisplayRole:
            return self._data_list[index.row()]
        elif role == Qt.SizeHintRole:
            return self._size_hints.get(index.row(), QSize(100, 30))

    def setData(self, index, value, role=Qt.EditRole):
        if role == Qt.SizeHintRole:
            self._size_hints[index.row()] = value
            self.dataChanged.emit(index, index, (role,))
            return True
        return False

    @property
    def data_list(self):
        return self._data_list

    @data_list.setter
    def data_list(self, data_list):
        self.beginResetModel()
        self._data_list = data_list.copy()
        self.endResetModel()


class StyledItemDelegate(QStyledItemDelegate):
    def createEditor(self, parent, option, index):
        editor = Editor(parent)
        model = index.model()
        model.setData(index, editor.sizeHint(), Qt.SizeHintRole)
        return editor

    def setEditorData(self, editor, index):
        value = index.data()
        editor.label.setText(value)


data = ["Apple", "Strawberry", "Cherry"]


class MainWindow(QMainWindow):
    def __init__(self):
        """
        Init main window
        """
        super().__init__()
        loadUi("main_window.ui", self)


class MyCtrl:
    def __init__(self, view):
        self.view = view

    def load_datalist(self):
        self.model = MyListModel()
        self.model.data_list = data
        self.view.listView.setModel(self.model)
        delegate = StyledItemDelegate(self.view.listView)
        self.view.listView.setItemDelegate(delegate)

        for i in range(self.model.rowCount()):
            index = self.model.index(i, 0)
            self.view.listView.openPersistentEditor(index)


if __name__ == "__main__":
    import sys

    app = QApplication(sys.argv)

    main = MainWindow()
    main.showMaximized()

    controller = MyCtrl(main)
    controller.load_datalist()

    sys.exit(app.exec_())