PyQt-QScrollArea滚动后更新布局时表头部件错位问题求助

我开发了一个自定义表格部件，基于QScrollArea嵌套QGridLayout实现，支持向单元格添加任意部件。表格边距处用QScrollArea作为表头，表格滚动时表头同步滚动。

遇到的问题：

• 当表格处于向下滚动状态时，添加/删除行列、更新表格或表头后，表格显示正常，但表头部件会下移到自身QScrollArea的视口内，导致表头编号与表格网格无法对齐。
• 当表格向上滚动时，表头部件与滚动区域顶部出现较大间隙。

表头实现细节：

• 每个表头段是包含QLabel的QWidget，所有表头段由模型存储。
• 更新表头时会先清除布局，再重新添加所有表头段。

UI_Header.py（仅UI部分） #

class Header(QtWidgets.QScrollArea):
    
    def __init__(self, direction: QtWidgets.QBoxLayout.Direction, parent: QtWidgets.QWidget | None = None) -> None:
        super().__init__(parent)

        self.setSizePolicy(QtWidgets.QSizePolicy.Policy.Fixed, QtWidgets.QSizePolicy.Policy.Fixed)
        self.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarPolicy.ScrollBarAlwaysOff)
        self.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarPolicy.ScrollBarAlwaysOff)
        self.setWidgetResizable(True)
        self.setFrameShape(QtWidgets.QFrame.Shape.NoFrame)
        self.setStyleSheet("background-color: red")

        self.header_widget = QtWidgets.QWidget(self)
        self.header_widget.setStyleSheet("background-color: blue")
        self.header_widget.setSizePolicy(QtWidgets.QSizePolicy.Policy.Fixed, QtWidgets.QSizePolicy.Policy.Fixed)  
        self.header_layout = QtWidgets.QBoxLayout(direction)
        self.header_layout.setSpacing(0)
        self.header_layout.setContentsMargins(0, 0, 0, 0)
        self.header_layout.setAlignment(QtCore.Qt.AlignmentFlag.AlignLeft)
        self.header_widget.setLayout(self.header_layout)
        self.setWidget(self.header_widget)

        if direction == QtWidgets.QBoxLayout.Direction.LeftToRight:
            self.setAlignment(QtCore.Qt.AlignmentFlag.AlignLeft)
            self.header_layout.setAlignment(QtCore.Qt.AlignmentFlag.AlignLeft)
        else:
            self.setAlignment(QtCore.Qt.AlignmentFlag.AlignTop)
            self.header_layout.setAlignment(QtCore.Qt.AlignmentFlag.AlignTop)

header.py（UI控制逻辑） #

class HeaderView(Header):
    itemResized = QtCore.pyqtSignal()

    def __init__(self, orientation: QtCore.Qt.Orientation, direction: QtWidgets.QBoxLayout.Direction, parent: QtWidgets.QWidget | None = ...) -> None:
        super().__init__(direction, parent)
        self.orientation = orientation
        self.direction = direction
        self.model = None


    def clear(self) -> None:
        for i in reversed(range(self.header_layout.count())):
            w = self.header_layout.takeAt(i).widget()
            self.header_layout.removeWidget(w)

    def update_header(self) -> None:
        self.clear()
        for i, hitem in enumerate(self.model.header(self.orientation)):
            hitem.resized.connect(self.itemResized.emit)
            hitem.isResizing.connect(self.set_resizing)
            if not hitem.model.text or hitem.model.orientation == QtCore.Qt.Orientation.Vertical:
                hitem.label.setText(str(i+1))
            self.header_layout.addWidget(hitem)
        self.header_widget.updateGeometry()

UI_Table.py #

class Table(QtWidgets.QScrollArea):
    def __init__(self, parent=None) -> None:
        super().__init__(parent)
        self.setUi()
        self.setObjectName("Table")
        self.setStyleSheet(fromStyle("Table"))
        self.setSizePolicy(QtWidgets.QSizePolicy.Policy.Expanding, QtWidgets.QSizePolicy.Policy.Expanding)       
    
    def setUi(self):
        self.setWidgetResizable(True)
        self.grid_widget = GridWidget(self)
        self.grid_widget.setSizePolicy(QtWidgets.QSizePolicy.Policy.Fixed, QtWidgets.QSizePolicy.Policy.Fixed)  
        self.grid_widget.setContentsMargins(0, 0, 0, 0)

        self.grid = QtWidgets.QGridLayout(self)
        self.grid.setContentsMargins(1, 1, 0, 0)
        self.grid.setSpacing(0)
        self.grid.setAlignment(QtCore.Qt.AlignmentFlag.AlignTop)
        self.grid_widget.setLayout(self.grid)
        self.setWidget(self.grid_widget)

        self.margins = QtCore.QMargins(30, 30, 0, 0)
        self.setViewportMargins(self.margins)

        self.hheaders = HeaderView(QtCore.Qt.Orientation.Horizontal, QtWidgets.QBoxLayout.Direction.LeftToRight, self)
        self.vheaders = HeaderView(QtCore.Qt.Orientation.Vertical, QtWidgets.QBoxLayout.Direction.TopToBottom, self)


    def scrollContentsBy(self, dx: int, dy: int) -> None:
        self.hheaders.scroll(dx, 0)
        self.vheaders.scroll(0, dy)
        self.updateGeometry()
        super().scrollContentsBy(dx, dy)

    def resizeEvent(self, a0: QtGui.QResizeEvent | None) -> None:
        rect = self.viewport().geometry()
        self.hheaders.setGeometry(
            rect.x() +1, rect.y() - self.margins.top(), rect.width(), self.margins.top()
        )
        self.vheaders.setGeometry(
            rect.x()  - self.margins.left(), rect.y() + 1, self.margins.left(), rect.height()
        )
        super().resizeEvent(a0)

已尝试的解决方案：

• 更新表头后调用updateGeometry()
• 设置滚动区域对齐方式
• 改用QGridLayout布局

上述方法均未解决问题，猜测可能与表格resizeEvent中设置表头几何的方式有关，希望获取解决思路。

内容的提问来源于stack exchange，提问作者Deator