为此,您可能需要一个项目委托。
我们的想法是,您将把基本项目绘制留给基类paint() 函数,然后在其上绘制一个虚拟按钮。
为了实现这一点,QStyleOptionButton 用于视图样式(从option 参数获得):您创建一个样式选项,init 从视图(option.widget,它将应用小部件的基本矩形、字体、调色板等),调整矩形以满足您的需要,最后绘制它。
为了更好地实现绘图(鼠标悬停效果,同时确保正确的绘图更新),您还需要将树形视图的鼠标跟踪设置为 True。除了代码中解释的其他检查外,这还允许您绘制虚拟按钮,包括其悬停或按下状态。
最后,当释放按钮并且鼠标在其边界内时,会发出buttonClicked 信号,并以当前索引作为参数。
class TreeButtonDelegate(QtWidgets.QStyledItemDelegate):
buttonClicked = QtCore.pyqtSignal(QtCore.QModelIndex, int)
def __init__(self, fsModel, *args, **kwargs):
super().__init__(*args, **kwargs)
self.fsModel = fsModel
self.clickedPaths = {}
self._mousePos = None
self._pressed = False
self.minimumButtonWidth = 32
def getOption(self, option, index):
btnOption = QtWidgets.QStyleOptionButton()
# initialize the basic options with the view
btnOption.initFrom(option.widget)
clickedCount = self.clickedPaths.get(self.fsModel.filePath(index), 0)
if clickedCount:
btnOption.text = '{}'.format(clickedCount)
else:
btnOption.text = 'NO'
# the original option properties should never be touched, so we can't
# directly use it's "rect"; let's create a new one from it
btnOption.rect = QtCore.QRect(option.rect)
# adjust it to the minimum size
btnOption.rect.setLeft(option.rect.right() - self.minimumButtonWidth)
style = option.widget.style()
# get the available space for the contents of the button
textRect = style.subElementRect(
QtWidgets.QStyle.SE_PushButtonContents, btnOption)
# get the margins between the contents and the border, multiplied by 2
# since they're used for both the left and right side
margin = style.pixelMetric(
QtWidgets.QStyle.PM_ButtonMargin, btnOption) * 2
# the width of the current button text
textWidth = btnOption.fontMetrics.width(btnOption.text)
if textRect.width() < textWidth + margin:
# if the width is too small, adjust the *whole* button rect size
# to fit the contents
btnOption.rect.setLeft(btnOption.rect.left() - (
textWidth - textRect.width() + margin))
return btnOption
def editorEvent(self, event, model, option, index):
# map the proxy index to the fsModel
srcIndex = index.model().mapToSource(index)
# I'm just checking if it's a file, if you want to check the extension
# you might need to use fsModel.fileName(srcIndex)
if not self.fsModel.isDir(srcIndex):
if event.type() in (QtCore.QEvent.Enter, QtCore.QEvent.MouseMove):
self._mousePos = event.pos()
# request an update of the current index
option.widget.update(index)
elif event.type() == QtCore.QEvent.Leave:
self._mousePos = None
elif (event.type() in (QtCore.QEvent.MouseButtonPress, QtCore.QEvent.MouseButtonDblClick)
and event.button() == QtCore.Qt.LeftButton):
# check that the click is within the virtual button rectangle
if event.pos() in self.getOption(option, srcIndex).rect:
self._pressed = True
option.widget.update(index)
if event.type() == QtCore.QEvent.MouseButtonDblClick:
# do not send double click events
return True
elif event.type() == QtCore.QEvent.MouseButtonRelease:
if self._pressed and event.button() == QtCore.Qt.LeftButton:
# emit the click only if the release is within the button rect
if event.pos() in self.getOption(option, srcIndex).rect:
filePath = self.fsModel.filePath(srcIndex)
count = self.clickedPaths.setdefault(filePath, 0)
self.buttonClicked.emit(index, count + 1)
self.clickedPaths[filePath] += 1
self._pressed = False
option.widget.update(index)
return super().editorEvent(event, model, option, index)
def paint(self, painter, option, index):
super().paint(painter, option, index)
srcIndex = index.model().mapToSource(index)
if not self.fsModel.isDir(srcIndex):
btnOption = self.getOption(option, srcIndex)
# remove the focus rectangle, as it will be inherited from the view
btnOption.state &= ~QtWidgets.QStyle.State_HasFocus
if self._mousePos is not None and self._mousePos in btnOption.rect:
# if the style supports it, some kind of "glowing" border
# will be shown on the button
btnOption.state |= QtWidgets.QStyle.State_MouseOver
if self._pressed == QtCore.Qt.LeftButton:
# set the button pressed state
btnOption.state |= QtWidgets.QStyle.State_On
else:
# ensure that there's no mouse over state (see above)
btnOption.state &= ~QtWidgets.QStyle.State_MouseOver
# finally, draw the virtual button
option.widget.style().drawControl(
QtWidgets.QStyle.CE_PushButton, btnOption, painter)
class MainMenu(QWidget):
def __init__(self, parent = None):
super(MainMenu, self).__init__(parent)
# ...
self.treeView = QTreeView(self)
self.treeView.setMouseTracking(True)
# ...
self.treeDelegate = TreeDelegate(self.model)
self.treeView.setItemDelegateForColumn(0, self.treeDelegate)
self.treeDelegate.buttonClicked.connect(self.treeButtonClicked)
# ...
def treeButtonClicked(self, index, count):
print('{} clicked {} times'.format(index.data(), count))
注意:我按照您在 cmets 中的要求实现了点击计数器(并使用辅助函数来容纳相应计算按钮大小的较长函数),请记住,这没有考虑重命名文件的可能性、删除和/或重新创建(或重命名的文件覆盖现有文件)。要获得这一点,您需要使用比简单的基于路径的字典更复杂的方法,可能通过实现 QFileSystemWatcher 并检查已删除/重命名的文件。
另请注意,为了加快速度,我将源文件系统模型添加到委托的 init 中,这样每次绘制或鼠标跟踪时都不需要找到它。