Pyqt 控件的信号槽事件定义方法

转载来自：http://my.oschina.net/midnite/blog/39399

Qt采用信号槽来设定UI界面上元素动作的事件绑定。自Qt4.5开始，引入了一个新的信号槽与事件绑定的方法。界面上控件可以发出的默认内容都已经由Qt库定义好了，我们只需要定义处理方法即可。

从Designer设计出的控件中会使用setObjectName设定控件的名字，这个名字就可以让我们快捷的定义指定信号槽对应的处理方法。通过@PyQt4.QtCore.pyqtslot()修饰方法可以完成这一动作。定义方法如下：

@PyQt4.QtCore.pyqtSlot(参数)     #这个参数请到SDK中找，写参数的类型即可
def on_对象名称_信号名称(self,参数)：
    #on接setObjectName设定的对象名字再接SDK中标出的信号名称，即可完成信号处理事件的定义
   pass

这种定义方法同样适用与自定义的信号槽。

首先需要定义信号：

class MyWidget(QWidget):
    Signal_NoParameters = PyQt4.QtCore.pyqtSignal()   # 无参数信号
    Signal_OneParameter = PyQt4.QtCore.pyqtSignal(int)  # 一个参数(整数)的信号

然后定义信号的激发：

class MyWidget(QWidget):
    def mousePressEvent(self, event):
        self.Signal_NoParameters.emit()  # 焕发无参数信号
        self.Signal_OneParameter.emit(1)  # 焕发一个参数(整数)的信号

定义槽函数：

class MyWidget(QWidget):
    @PyQt4.QtCore.pyqtSlot()
    def setValue_NoParameters(self):
        pass
    @PyQt4.QtCore.pyqtSlot(int)
    def setValue_OneParameter(self,nIndex):
        pass

 之后需要将信号与槽进行连接：

widget.Signal_NoParameters.connect(self.setValue_NoParameters,Qt.QueuedConnection)
widget.Signal_OneParameter.connect(self.setValue_OneParameter,Qt.QueuedConnection)

---

emit发送信号

#-*-coding:utf-8-*-
from PyQt4 import QtGui, QtCore
from PyQt4.QtGui import *
from PyQt4.QtCore import *

class MyButton(QtGui.QPushButton):
    def __init__(self):
        super(MyButton,self).__init__()
        self.connect(self, QtCore.SIGNAL("clicked()"), self.myClicked)
        self.connect(self, QtCore.SIGNAL("myclicked()"), self.showMsg)
    def myClicked(self):
        self.emit(QtCore.SIGNAL("myclicked()"))
    def showMsg(self):
        print('test')
    

if __name__ == "__main__":
    import sys
    app = QApplication(sys.argv)  #MyApplication
    main_widget = MyButton()
    main_widget.show()
    sys.exit(app.exec_())

发送带参数的信号

#-*-coding:utf-8-*-
from PyQt4 import QtGui, QtCore
from PyQt4.QtGui import *
from PyQt4.QtCore import *

class MyButton(QtGui.QPushButton):
    def __init__(self, *args, **kwargs):
        QtGui.QPushButton.__init__(self, *args, **kwargs)
        self.connect(self, QtCore.SIGNAL("clicked()"), self.myClicked)
        self.connect(self, QtCore.SIGNAL("myclicked(int)"), self.showMsg)

    def myClicked(self):
        param=123
        self.emit(QtCore.SIGNAL("myclicked(int)"),param)
    def showMsg(self,a):
        print(a)
    

if __name__ == "__main__":
    import sys
    app = QApplication(sys.argv)  #MyApplication
    main_widget = MyButton()
    main_widget.show()
    sys.exit(app.exec_())

接收另外页面的槽

#!/usr/bin/python  
#-*-coding:utf-8-*-

from PyQt4.QtGui import *
from PyQt4.QtCore import *
from PyQt4.Qt import *

class TitleWidget(QWidget):
    def __init__(self, parent=None):
        super(TitleWidget, self).__init__(parent)
        self.skin_button = QPushButton('dailog')
        self.connect(self.skin_button, SIGNAL("clicked()"), self, SIGNAL("showSkin()"))
        
        main_layout = QVBoxLayout()
        main_layout.addWidget(self.skin_button)
        self.setLayout(main_layout)


# 主入口文件
class MainWidget(QWidget):
    def __init__(self, parent=None):
        super(MainWidget, self).__init__(parent)
        self.title_widget = TitleWidget(self)
        self.title_widget.setFixedHeight(100)
        self.setMinimumSize(100, 100)

        main_layout = QVBoxLayout()
        main_layout.addWidget(self.title_widget)
        main_layout.setSpacing(0)
        self.setLayout(main_layout)
        self.connect(self.title_widget, SIGNAL("showSkin()"), self, SLOT('showSkinWidget()'))   # 等同  self.connect(self.title_widget, SIGNAL("showSkin()"),self.showSkinWidget)

        self.title_widget.skin_button.clicked.connect(self.onclick)
        self.connect(self,SIGNAL('myclicked()'),self.myclickeddd)
        
    def onclick(self):
        print('a')
        self.emit(SIGNAL("myclicked()"))
        
    def myclickeddd(self):
        print('b')
    
    @pyqtSlot()
    def showSkinWidget(self):
        print('sdf')

if __name__ == "__main__":
    import sys
    app = QApplication(sys.argv)  #MyApplication
    main_widget = MainWidget()
    main_widget.show()
    sys.exit(app.exec_())