如果使用自定義信號，一定要記得信號是類變量，必須在類中定義，不能在實例方法中定義，否則后面發射信號和連接槽方法時都會報錯。
案例：
class configWin(ui_configWin.Ui_configWin,QtWidgets.QWidget):
def __init__(self,parent=None):
super().__init__(parent)
self.setupUi(self)
self.sizeChanged = QtCore.pyqtSignal(int)
def resize(self,width,height):
self.sizeChanged.emit(width)
print("sizeChanged....")
super().resize(width,height)
class mainWin(QtWidgets.QMainWindow,ui_mainWin.Ui_mainWindow):
def __init__(self):
super().__init__()
self.setupUi(self)
self.configWin = configWin(self)
self.configWin.sizeChanged.connect(self.sizeChanged)
結果執行時報錯：
AttributeError: ‘configWin’ object has no attribute ‘sizeChanged’
AttributeError: ‘PyQt5.QtCore.pyqtSignal’ object has no attribute ‘connect’
正確的做法應該是：
class configWin(ui_configWin.Ui_configWin,QtWidgets.QWidget):
sizeChanged = QtCore.pyqtSignal(int)
def __init__(self,parent=None):
super().__init__(parent)
self.setupUi(self)
def resize(self,width,height):
self.sizeChanged.emit(width)
super().resize(width,height)
class mainWin(QtWidgets.QMainWindow,ui_mainWin.Ui_mainWindow):
def __init__(self):
super().__init__()
self.setupUi(self)
self.configWin = configWin(self)
self.configWin.sizeChanged.connect(self.sizeChanged)
更多自定義信號的內容請參考《第15.19節 PyQt(Python+Qt)入門學習：自定義信號與槽連接》。
