setStyleSheet或QStyledItemDelegate QTreeView中的节点

Question

我正在尝试更改QTreeView中特定节点的图标。节点将使用QCheckbox，并且基于应用程序逻辑，一些节点将改为使用其他图标进行节点选择/未选择状态。

下面的示例显示了如何为整个树设置样式表，但我不认为可以为树中的单个节点设置样式表。

#Based on http://*.com/questions/5374168/unable-to-select-checkbox-inside-treeview 
import sys 
from PyQt4.QtCore import * 
from PyQt4.QtGui import * 
from PyQt4 import QtGui, QtCore 

class Window(QtGui.QWidget): 
    changeStyleTriggered = QtCore.pyqtSignal() 

    def __init__(self): 
     QtGui.QWidget.__init__(self) 
     self.createTree() 
     self.connectSlots() 

    def createTree(self): 
     data = ['A', 'B', 'C', 'D', 'E', 'F'] 
     model = MyTreeView(data) 
     self.treeView = QTreeView() 
     self.treeView.setModel(model) 
     layout = QtGui.QVBoxLayout() 
     layout.addWidget(self.treeView) 
     self.changeIconPushButton = QtGui.QPushButton("Change a single icon") 
     layout.addWidget(self.changeIconPushButton) 
     self.setLayout(layout) 

    def fireChangeStyleSignal(self): 
     self.changeStyleTriggered.emit() 

    @pyqtSlot() 
    def changeStyleSignal(self): 
     print(">>changeStyleSignal()") 
     self.setStyleSheet("QTreeView::indicator:unchecked {image: url(:/icons/image.png);}") 

    def connectSlots(self): 
     self.changeStyleTriggered.connect(self.changeStyleSignal) 
     self.changeIconPushButton.clicked.connect(self.fireChangeStyleSignal) 

class TestItem(): 
    def __init__(self, name, checked): 
     self.checked = checked 
     self.name = name 

class MyTreeView(QAbstractListModel): 
    def __init__(self, args, parent=None): 
     super(StbTreeView, self).__init__(parent) 

     self.args = [] 
     for item_name in args: 
      self.args.append(TestItem(item_name, False)) 

     for item in self.args: 
      print (item.name) 

    def rowCount(self, parent): 
     return len(self.args) 

    def headerData(self, section, orientation, role): 
     if role == Qt.DisplayRole: 
      if orientation == Qt.Horizontal: 
       return "Nodes" 

    def flags(self, index): 
     return Qt.ItemIsUserCheckable | Qt.ItemIsEditable | Qt.ItemIsSelectable | Qt.ItemIsEnabled 

    def data(self, index, role=Qt.DisplayRole): 
     if role == Qt.DisplayRole: 
      row = index.row() 
      print (self.args[row].name) 
      return self.args[row].name 

     if role == Qt.CheckStateRole: 
      row = index.row() 
      print (self.args[row].checked) 
      if self.args[row].checked == False: 
       return Qt.Unchecked 
      else: 
       return Qt.Checked 

    def setData(self, index, value, role): 
     if role == Qt.CheckStateRole: 
      row = index.row() 
      self.args[row].checked = not self.args[row].checked    
     return True 

def main(): 
    myapp = QApplication(sys.argv) 

    window = Window() 
    window.show() 
    myapp.exec_() 

if __name__ == '__main__': 
    main() 

另一种选择是使用QStyledItemDelegate。下面是一个改变字体的小类，但我还没有弄清楚如何使用委托来更改单个图标。

class BoldDelegate(QtGui.QStyledItemDelegate): 
    def paint(self, painter, option, index): 
     option.font.setWeight(QtGui.QFont.Bold) 
     QtGui.QStyledItemDelegate.paint(self, painter, option, index) 

，并使用它这个（在对QTreeView则一@pyqtSlot（）如）运行：

self.setItemDelegate(BoldDelegate(self)) 

任何想法？

Answer 1

A QCheckBox不使用图标来显示其状态。您应该首先创建一个项目，通过任何方式，您可以获得一个按照您的意愿操作的小部件，并且具有正确的选中/未选中外观。

一旦你有了，你会让你的委托基于模型的数据项的某些属性创建这样的项目。例如，您可能有一个自定义角色，向您的委托表明应使用非默认控件类来编辑该项目。