根据项目的文本本身更改项目的前景色
Change foreground color of items based on the item's text itself
我有一个包含 5 列的 QTreeView，我为其中的 2 列（第 1 列和第 2 列）设置了一个 QComboBox 委托。他们都有相同的代表，并且他们必须有相同的下拉列表。假设列表始终为：["Next", "Stop"]。
到目前为止一切顺利：代表工作完美。
现在的问题是：我希望第 1 列和第 2 列的项目根据文本本身以不同颜色显示文本。例如：如果文本是“Next”，文本的颜色应该是绿色，如果文本是“Stop”，那么颜色应该是红色。
经过一番搜索，我决定使用委托来设置颜色。我找到了不同的解决方案，但唯一对我有用的解决方案是这个（参见 paint() 函数）：
class ComboBoxDelegate(QtWidgets.QStyledItemDelegate):
def paint(self, painter, option, index):
painter.save()
text = index.data(Qt.DisplayRole)
if text == 'Next':
color = GREEN
elif text == 'Stop':
color = RED
else:
color = BLACK
painter.setPen(QPen(color))
painter.drawText(option.rect, Qt.AlignLeft | Qt.AlignVCenter, text)
painter.restore()
def createEditor(self, parent, option, index):
editor = QtWidgets.QComboBox(parent)
editor.currentIndexChanged.connect(self.commitEditor)
return editor
# @QtCore.Slot
def commitEditor(self):
editor = self.sender()
self.commitData.emit(editor)
if isinstance(self.parent(), QtWidgets.QAbstractItemView):
self.parent().updateEditorGeometries()
self.closeEditor.emit(editor)
def setEditorData(self, editor, index):
try:
values = index.data(QtCore.Qt.UserRole + 100)
val = index.data(QtCore.Qt.UserRole + 101).strip('<>')
editor.clear()
for i, x in enumerate(values):
editor.addItem(x, x)
if val == x:
editor.setCurrentIndex(i)
except (TypeError, AttributeError):
LOG.warning(f"No values in drop-down list for item at row: {index.row()} and column: {index.column()}")
def setModelData(self, editor, model, index):
values = index.data(QtCore.Qt.UserRole + 100)
if values:
ix = editor.currentIndex()
model.setData(index, values[ix], QtCore.Qt.UserRole + 101)
model.setData(index, values[ix], QtCore.Qt.DisplayRole)
def updateEditorGeometry(self, editor, option, index):
editor.setGeometry(option.rect)
如下图所示，选择和悬停无法正常工作：
我做错了什么？
最小可重现示例（记得导入 ComboBoxDelegate）：
import sys
from PySide2.QtGui import QStandardItemModel, QStandardItem
from PySide2.QtWidgets import QTreeView, QApplication, QMainWindow
from combo_box_delegate import ComboBoxDelegate
COLUMN_HEADER_LIST = ["0", "1", "2", "3", "4"]
class MyTreeView(QTreeView):
def __init__(self):
super(MyTreeView, self).__init__()
self.model = QStandardItemModel()
self.root = self.model.invisibleRootItem()
self.setModel(self.model)
delegate = ComboBoxDelegate(self)
self.setItemDelegateForColumn(1, delegate)
self.setItemDelegateForColumn(2, delegate)
self.data = {
"a": {
"b": {
"c": ["Next", "Stop", "1", "Hello World!"],
"d": ["Next", "Stop", "2", "Hello World!"],
"e": ["Next", "Stop", "3", "Hello World!"],
"f": ["Next", "Stop", "4", "Hello World!"]
}
}
}
self.populate_tree(self.root, self.data)
self._format_columns()
def populate_tree(self, parent, data):
for key, value in data.items():
if isinstance(value, dict):
child = QStandardItem(key)
parent.appendRow(child)
self.populate_tree(child, data[key])
elif isinstance(value, list):
items = [QStandardItem(key)] + [QStandardItem(str(val)) for val in value]
parent.appendRow(items)
def _format_columns(self):
self.model.setHorizontalHeaderLabels(COLUMN_HEADER_LIST)
self.expandAll()
class Main(QMainWindow):
def __init__(self):
super(Main, self).__init__()
tree = MyTreeView()
self.setCentralWidget(tree)
self.setMinimumWidth(600)
self.setMinimumHeight(400)
if __name__ == "__main__":
app = QApplication(sys.argv)
main_window = Main()
main_window.show()
app.exec_()
您注意到的奇怪选择问题可能是因为设置了当前选择。
先设置根模型索引，再设置当前索引。
然后设置回树当前项。
大致如下所述（未测试。还要注意语法。）
yourComboBox.setRootModelIndex(yourTree.currentIndex())
yourComboBox.setCurrentIndex(index)
yourTree.setCurrentItem(yourTree.invisibleRootItem(),0)
物品的绘制比较特殊，一般不建议重写paint()方法，建议在initStyleOption()方法中修改QStyleOptionViewItem的属性，用于绘画，例如更改 QPalette:
from PySide2.QtCore import Qt
from PySide2.QtGui import QBrush, QColor, QPalette
from PySide2.QtWidgets import QAbstractItemView, QComboBox, QStyledItemDelegate
RED = "red"
BLACK = "black"
GREEN = "green"
class ComboBoxDelegate(QStyledItemDelegate):
def initStyleOption(self, option, index):
super().initStyleOption(option, index)
text = index.data(Qt.DisplayRole)
if text == "Next":
color = GREEN
elif text == "Stop":
color = RED
else:
color = BLACK
option.palette.setBrush(QPalette.Text, QBrush(QColor(color)))
def createEditor(self, parent, option, index):
editor = QComboBox(parent)
editor.currentIndexChanged.connect(self.commitEditor)
return editor
# @QtCore.Slot
def commitEditor(self):
editor = self.sender()
self.commitData.emit(editor)
if isinstance(self.parent(), QAbstractItemView):
self.parent().updateEditorGeometries()
self.closeEditor.emit(editor)
def setEditorData(self, editor, index):
try:
values = index.data(Qt.UserRole + 100)
val = index.data(Qt.UserRole + 101).strip("<>")
editor.clear()
for i, x in enumerate(values):
editor.addItem(x, x)
if val == x:
editor.setCurrentIndex(i)
except (TypeError, AttributeError):
pass
# LOG.warning(f"No values in drop-down list for item at row: {index.row()} and column: {index.column()}")
def setModelData(self, editor, model, index):
values = index.data(Qt.UserRole + 100)
if values:
ix = editor.currentIndex()
model.setData(index, values[ix], QtCore.Qt.UserRole + 101)
model.setData(index, values[ix], QtCore.Qt.DisplayRole)
def updateEditorGeometry(self, editor, option, index):
editor.setGeometry(option.rect)
我有一个包含 5 列的 QTreeView，我为其中的 2 列（第 1 列和第 2 列）设置了一个 QComboBox 委托。他们都有相同的代表，并且他们必须有相同的下拉列表。假设列表始终为：["Next", "Stop"]。
到目前为止一切顺利：代表工作完美。
现在的问题是：我希望第 1 列和第 2 列的项目根据文本本身以不同颜色显示文本。例如：如果文本是“Next”，文本的颜色应该是绿色，如果文本是“Stop”，那么颜色应该是红色。
经过一番搜索，我决定使用委托来设置颜色。我找到了不同的解决方案，但唯一对我有用的解决方案是这个（参见 paint() 函数）：
class ComboBoxDelegate(QtWidgets.QStyledItemDelegate):
def paint(self, painter, option, index):
painter.save()
text = index.data(Qt.DisplayRole)
if text == 'Next':
color = GREEN
elif text == 'Stop':
color = RED
else:
color = BLACK
painter.setPen(QPen(color))
painter.drawText(option.rect, Qt.AlignLeft | Qt.AlignVCenter, text)
painter.restore()
def createEditor(self, parent, option, index):
editor = QtWidgets.QComboBox(parent)
editor.currentIndexChanged.connect(self.commitEditor)
return editor
# @QtCore.Slot
def commitEditor(self):
editor = self.sender()
self.commitData.emit(editor)
if isinstance(self.parent(), QtWidgets.QAbstractItemView):
self.parent().updateEditorGeometries()
self.closeEditor.emit(editor)
def setEditorData(self, editor, index):
try:
values = index.data(QtCore.Qt.UserRole + 100)
val = index.data(QtCore.Qt.UserRole + 101).strip('<>')
editor.clear()
for i, x in enumerate(values):
editor.addItem(x, x)
if val == x:
editor.setCurrentIndex(i)
except (TypeError, AttributeError):
LOG.warning(f"No values in drop-down list for item at row: {index.row()} and column: {index.column()}")
def setModelData(self, editor, model, index):
values = index.data(QtCore.Qt.UserRole + 100)
if values:
ix = editor.currentIndex()
model.setData(index, values[ix], QtCore.Qt.UserRole + 101)
model.setData(index, values[ix], QtCore.Qt.DisplayRole)
def updateEditorGeometry(self, editor, option, index):
editor.setGeometry(option.rect)
如下图所示，选择和悬停无法正常工作：
我做错了什么？
最小可重现示例（记得导入 ComboBoxDelegate）：
import sys
from PySide2.QtGui import QStandardItemModel, QStandardItem
from PySide2.QtWidgets import QTreeView, QApplication, QMainWindow
from combo_box_delegate import ComboBoxDelegate
COLUMN_HEADER_LIST = ["0", "1", "2", "3", "4"]
class MyTreeView(QTreeView):
def __init__(self):
super(MyTreeView, self).__init__()
self.model = QStandardItemModel()
self.root = self.model.invisibleRootItem()
self.setModel(self.model)
delegate = ComboBoxDelegate(self)
self.setItemDelegateForColumn(1, delegate)
self.setItemDelegateForColumn(2, delegate)
self.data = {
"a": {
"b": {
"c": ["Next", "Stop", "1", "Hello World!"],
"d": ["Next", "Stop", "2", "Hello World!"],
"e": ["Next", "Stop", "3", "Hello World!"],
"f": ["Next", "Stop", "4", "Hello World!"]
}
}
}
self.populate_tree(self.root, self.data)
self._format_columns()
def populate_tree(self, parent, data):
for key, value in data.items():
if isinstance(value, dict):
child = QStandardItem(key)
parent.appendRow(child)
self.populate_tree(child, data[key])
elif isinstance(value, list):
items = [QStandardItem(key)] + [QStandardItem(str(val)) for val in value]
parent.appendRow(items)
def _format_columns(self):
self.model.setHorizontalHeaderLabels(COLUMN_HEADER_LIST)
self.expandAll()
class Main(QMainWindow):
def __init__(self):
super(Main, self).__init__()
tree = MyTreeView()
self.setCentralWidget(tree)
self.setMinimumWidth(600)
self.setMinimumHeight(400)
if __name__ == "__main__":
app = QApplication(sys.argv)
main_window = Main()
main_window.show()
app.exec_()
您注意到的奇怪选择问题可能是因为设置了当前选择。
先设置根模型索引，再设置当前索引。 然后设置回树当前项。
大致如下所述（未测试。还要注意语法。）
yourComboBox.setRootModelIndex(yourTree.currentIndex())
yourComboBox.setCurrentIndex(index)
yourTree.setCurrentItem(yourTree.invisibleRootItem(),0)
物品的绘制比较特殊，一般不建议重写paint()方法，建议在initStyleOption()方法中修改QStyleOptionViewItem的属性，用于绘画，例如更改 QPalette:
from PySide2.QtCore import Qt
from PySide2.QtGui import QBrush, QColor, QPalette
from PySide2.QtWidgets import QAbstractItemView, QComboBox, QStyledItemDelegate
RED = "red"
BLACK = "black"
GREEN = "green"
class ComboBoxDelegate(QStyledItemDelegate):
def initStyleOption(self, option, index):
super().initStyleOption(option, index)
text = index.data(Qt.DisplayRole)
if text == "Next":
color = GREEN
elif text == "Stop":
color = RED
else:
color = BLACK
option.palette.setBrush(QPalette.Text, QBrush(QColor(color)))
def createEditor(self, parent, option, index):
editor = QComboBox(parent)
editor.currentIndexChanged.connect(self.commitEditor)
return editor
# @QtCore.Slot
def commitEditor(self):
editor = self.sender()
self.commitData.emit(editor)
if isinstance(self.parent(), QAbstractItemView):
self.parent().updateEditorGeometries()
self.closeEditor.emit(editor)
def setEditorData(self, editor, index):
try:
values = index.data(Qt.UserRole + 100)
val = index.data(Qt.UserRole + 101).strip("<>")
editor.clear()
for i, x in enumerate(values):
editor.addItem(x, x)
if val == x:
editor.setCurrentIndex(i)
except (TypeError, AttributeError):
pass
# LOG.warning(f"No values in drop-down list for item at row: {index.row()} and column: {index.column()}")
def setModelData(self, editor, model, index):
values = index.data(Qt.UserRole + 100)
if values:
ix = editor.currentIndex()
model.setData(index, values[ix], QtCore.Qt.UserRole + 101)
model.setData(index, values[ix], QtCore.Qt.DisplayRole)
def updateEditorGeometry(self, editor, option, index):
editor.setGeometry(option.rect)