背景
Qt中的表格控件或树状图控件都提供了单元格基础的一些样式修改，可以通过qss设置，但是如果需要更加特性化的内容就需要实现代理QStyledItemDelegate
实现
继承QStyledItemDelegate，并按需要重写6个函数
def paint(self, painter: QPainter, option: QStyleOptionViewItem, index: QModelIndex)
这个函数是用于绘制单元格的背景，可以通过painter绘制点线面，还可以绘制控件样式，可以根据index单独控制某个单元格的背景。像以下代码就是在(1, 1)绘制了一张图片，(2, 2)绘制了一个进度条，(3, 2)绘制了一个按钮。
python
def paint(self, painter: QPainter, option: QStyleOptionViewItem, index: QModelIndex):
# 绘制单元格背景，不单止可以绘制线条、图片、还可以绘制进度条、按钮等控件
if index.row() == 1 and index.column() == 1:
rect: QRectF = option.rect
pixmap = QPixmap("ico.png")
pixmap = pixmap.scaled(rect.width(), rect.height(), Qt.KeepAspectRatio)
painter.drawPixmap(rect.x(), rect.y(), pixmap.width(), pixmap.height(), pixmap)
elif index.row() == 2 and index.column() == 2:
progressBarStyled = QStyleOptionProgressBar()
progressBarStyled.rect = option.rect
progressBarStyled.minimum = 0
progressBarStyled.maximum = 100
progressBarStyled.progress = int(index.data())
progressBarStyled.text = f"{int(index.data())}%"
progressBarStyled.state = option.state
progressBarStyled.textVisible = True
progressBarStyled.direction = option.direction
QApplication.style().drawControl(QStyle.CE_ProgressBar, progressBarStyled, painter)
return
elif index.row() == 3 and index.column() == 2:
btnStyled = QStyleOptionButton()
btnStyled.rect = option.rect
btnStyled.state = option.state
btnStyled.text = f"click"
btnStyled.direction = option.direction
QApplication.style().drawControl(QStyle.CE_PushButton, btnStyled, painter)
return
return super().paint(painter, option, index)
def editorEvent(self, event: QEvent, model, option, index)
那么绘制出来的按钮如何触发点击事件呢，就是重写这个editorEvent函数，像以下代码就是判断了当这个单元格被按下时触发clicked信号发出
python
def editorEvent(self, event: QEvent, model, option, index):
# 单元格事件处理
if index.row() == 3 and index.column() == 2:
if event.type() == QEvent.MouseButtonPress:
model.setData(index, "click")
self.clicked.emit("click")
return True
return super().editorEvent(event, model, option, index)def createEditor(self, parent, option, index)
那么如果需要双击进入编辑单元格模式时显示控件编辑，即有可能需要是下拉框选择内容，就可以通过重写这个函数实现
python
def createEditor(self, parent, option, index):
# 创建单元格编辑器，即双击单元格编辑时创建的编辑器
if index.row() == 0 and index.column() == 0:
spinBox = QDoubleSpinBox(parent)
spinBox.setSingleStep(0.1)
spinBox.setRange(0, 100)
return spinBox
if index.row() == 4 and index.column() == 4:
combobox = QComboBox(parent)
combobox.addItems(["None", "Left", "Right"])
return combobox
return super().createEditor(parent, option, index)
def updateEditorGeometry(self, editor, option, index)
如果需要修改由createEditor创建出来的控件的位置大小，可以通过重写这个函数实现，代码实现的是将(4, 4)内的下拉框位置大小修改为单元格的一半
python
def updateEditorGeometry(self, editor, option, index):
# 更新单元格编辑器的几何形状，即设置编辑器的位置和大小
if index.row() == 4 and index.column() == 4:
rect = option.rect
editor.setGeometry(rect.x(), rect.y(), rect.width(), rect.height() / 2)
return
return super().updateEditorGeometry(editor, option, index)
def setEditorData(self, editor, index)
Qt原本已经实现了单元格的数据添加到单元格编辑控件里面了，即如果双击单元格后显示的是一个doubleSpinBox的话，单元格显示的是80，那么SpinBox里显示的数据也是80。如果需要自定义值，例如一定要保证这个SpinBox的值一直是80，那么就可以重写这个函数实现。
python
def setEditorData(self, editor, index):
# 设置单元格数据编辑器的数据
if index.row() == 0 and index.column() == 0:
editor.setValue(50)
return
return super().setEditorData(editor, index)
一直是保持50
def setModelData(self, editor, model, index)
Qt原本也实现了编辑器控件修改后的值会直接添加到单元格中。即双击后显示的SpinBox值修改成100后，单元格恢复成查看模式时显示的就是100。如果需要保证单元格显示的值一直不变，那么就可以通过重写这个函数实现
python
def setModelData(self, editor, model, index):
# 通过编辑器修改值后，设置显示到单元格中的数据
if index.row() == 0 and index.column() == 0:
model.setData(index, 80)
return
return super().setModelData(editor, model, index) 
代码就是实现了不管编辑成什么数值，显示的都是80.
所以最后两个函数可以按需求确认是否需要重新实现
完整代码
python
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
from PyQt5.QtCore import *
class StyledItemDelegate(QStyledItemDelegate):
clicked = pyqtSignal(str)
def __init__(self, parent=None):
super().__init__(parent)
def paint(self, painter: QPainter, option: QStyleOptionViewItem, index: QModelIndex):
# 绘制单元格背景，不单止可以绘制线条、图片、还可以绘制进度条、按钮等控件
if index.row() == 1 and index.column() == 1:
rect: QRectF = option.rect
pixmap = QPixmap("ico.png")
pixmap = pixmap.scaled(rect.width(), rect.height(), Qt.KeepAspectRatio)
painter.drawPixmap(rect.x(), rect.y(), pixmap.width(), pixmap.height(), pixmap)
elif index.row() == 2 and index.column() == 2:
progressBarStyled = QStyleOptionProgressBar()
progressBarStyled.rect = option.rect
progressBarStyled.minimum = 0
progressBarStyled.maximum = 100
progressBarStyled.progress = int(index.data())
progressBarStyled.text = f"{int(index.data())}%"
progressBarStyled.state = option.state
progressBarStyled.textVisible = True
progressBarStyled.direction = option.direction
QApplication.style().drawControl(QStyle.CE_ProgressBar, progressBarStyled, painter)
return
elif index.row() == 3 and index.column() == 2:
btnStyled = QStyleOptionButton()
btnStyled.rect = option.rect
btnStyled.state = option.state
btnStyled.text = f"click"
btnStyled.direction = option.direction
QApplication.style().drawControl(QStyle.CE_PushButton, btnStyled, painter)
return
return super().paint(painter, option, index)
def editorEvent(self, event: QEvent, model, option, index):
# 单元格事件处理
if index.row() == 3 and index.column() == 2:
if event.type() == QEvent.MouseButtonPress:
model.setData(index, "click")
self.clicked.emit("click")
return True
return super().editorEvent(event, model, option, index)
def createEditor(self, parent, option, index):
# 创建单元格编辑器，即双击单元格编辑时创建的编辑器
if index.row() == 0 and index.column() == 0:
spinBox = QDoubleSpinBox(parent)
spinBox.setSingleStep(0.1)
spinBox.setRange(0, 100)
return spinBox
if index.row() == 4 and index.column() == 4:
combobox = QComboBox(parent)
combobox.addItems(["None", "Left", "Right"])
return combobox
return super().createEditor(parent, option, index)
def updateEditorGeometry(self, editor, option, index):
# 更新单元格编辑器的几何形状，即设置编辑器的位置和大小
if index.row() == 4 and index.column() == 4:
rect = option.rect
editor.setGeometry(rect.x(), rect.y(), rect.width(), rect.height() / 2)
return
return super().updateEditorGeometry(editor, option, index)
def setEditorData(self, editor, index):
# 设置单元格数据编辑器的数据
if index.row() == 0 and index.column() == 0:
editor.setValue(50)
return
return super().setEditorData(editor, index)
def setModelData(self, editor, model, index):
# 通过编辑器修改值后，设置显示到单元格中的数据
if index.row() == 0 and index.column() == 0:
model.setData(index, 80)
return
return super().setModelData(editor, model, index)