qcombobox.lineedit.set alignment崩溃

这个问题可能是因为QComboBox的lineEdit属性为null，而你尝试对null对象进行set alignment操作导致的崩溃。你可以先确保QComboBox中有lineEdit对象存在，再进行set alignment操作。可以通过如下代码检查lineEdit是否存在：

if comboBox.lineEdit() is None:
    # lineEdit does not exist, handle error here
else:
    comboBox.lineEdit().setAlignment(Qt.AlignCenter)  # set alignment