如何禁用 QTreeView 上的一行扩展？

Question

我想让这一行没有展开的胡萝卜，但仍然可以被选择。

我试过这个：

import sys
from PySide2.QtWidgets import QApplication, QMainWindow, QTreeView, QVBoxLayout, QWidget, QAbstractItemView, QSizePolicy, QStyledItemDelegate
from PySide2.QtCore import Qt, QModelIndex

class CustomItemDelegate(QStyledItemDelegate):
    def sizeHint(self, option, index):
        size = super().sizeHint(option, index)
        if index.row() == self.model.max_display_rows:
            size.setWidth(0)  # Hide the expanding icon
        return size

class CustomItemModel(QAbstractItemModel):
    def __init__(self, data, parent=None):
        super().__init__(parent)
        self.data = data
        self.max_display_rows = 5

    # ... (rest of the model methods)

class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()

        self.setWindowTitle("Custom Item Model Example")
        self.setGeometry(100, 100, 400, 300)

        data = ["Item {}".format(i) for i in range(1, 11)]

        self.model = CustomItemModel(data)
        self.treeView = QTreeView()
        self.treeView.setModel(self.model)
        self.treeView.setSelectionBehavior(QAbstractItemView.SelectRows)
        self.treeView.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)

        delegate = CustomItemDelegate(self.treeView)
        self.treeView.setItemDelegate(delegate)

        layout = QVBoxLayout()
        layout.addWidget(self.treeView)

        central_widget = QWidget()
        central_widget.setLayout(layout)
        self.setCentralWidget(central_widget)

def main():
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())

if __name__ == "__main__":
    main()

不起作用。

Answer 1

您可以执行类似的操作来不绘制箭头并且不展开项目。

class TreeView(QTreeView):

    def drawBranches(self, painter, rect, index):
        if index.row() == self.model().max_display_rows:
            return # do not draw branch
        super().drawBranches(painter, rect, index)


class MainWindow(QMainWindow):
    def __init__(self):
        ...
        self.treeView = TreeView()
        self.treeView.expanded[QModelIndex].connect(
            lambda index: index.row() == self.treeView.model().max_display_rows and self.treeView.collapse(index)
            ) # immediately collapse index
        ...