pyqt 动态增加 下拉框 标签 显示不全

pyqt实现下拉框 和 标签 显示内容不被 UI剪掉，能完整显示的代码如下：

label_3 = QtGui.QLabel(mainwin)txt = "1111111111111111111111111111000009999999999999999999999999999999999999999999999"metrics = QFontMetrics(label_3.font())w = metrics.width(txt)label_3.setGeometry(QtCore.QRect(20, 20, w, 80))label_3.setObjectName(_fromUtf8("label_3"))label_3.setText(_translate("MainWindow", txt, None))l = ['123' , '3451111111111111', '1111111111', '0000000000000', '123']comboBox_2 = QtGui.QComboBox(mainwin)txt = (max(l, key=len))metrics = QFontMetrics(comboBox_2.font())w = metrics.width(txt)comboBox_2.setGeometry(QtCore.QRect(80, 5, 20, 20))comboBox_2.setMinimumWidth(w)comboBox_2.setObjectName(_fromUtf8("comboBox_2"))comboBox_2.addItems(l)comboBox_2.setSizeAdjustPolicy(QtGui.QComboBox.AdjustToContents)

不过QT5貌似有bug，见 https://forum.qt.io/topic/25859/how-can-i-increase-the-size-of-the-drop-down-list-of-a-qcombobox/8