如何使用新语法将自定义信号连接到pyside中的插槽？

Question

这是视频教程中的一个示例:

#!/usr/bin/env python3

import sys
from PySide.QtCore import *
from PySide.QtGui import *

class ZeroSpinBox(QSpinBox):

    zeros = 0

    def __init__(self):
        super().__init__()
        self.valueChanged.connect(self.checkzero)

    def checkzero(self):
        if self.value() == 0:
            self.zeros += 1
            self.emit(SIGNAL("atzero(int)"), self.zeros)



class Form(QDialog):

    def __init__(self):
        super().__init__()

        dial = QDial()
        dial.setNotchesVisible(True)
        zerospinbox = ZeroSpinBox()
        layout = QHBoxLayout()
        layout.addWidget(dial)
        layout.addWidget(zerospinbox)
        self.setLayout(layout)

        dial.valueChanged.connect(zerospinbox.setValue)
        zerospinbox.valueChanged.connect(dial.setValue)
        # zerospinbox.atzero.connect(self.announce)
        self.connect(zerospinbox, SIGNAL("atzero(int)"), self.announce)

        self.setWindowTitle("Signals")

    def announce(self, zeros):
        print("zerospinbox has been at zero " + str(zeros) + " times.")



app = QApplication(sys.argv)
form = Form()
form.show()
app.exec_()

请注意,我为zerospinbox对象建立了两个连接,第一个使用新的连接语法,第二个使用旧语法.还有一行用于使用新语法进行相同的第二次连接,但它不起作用,因此它被注释掉了.atzero信号是定制的,似乎信号使得这对新语法不起作用.这是由于排放方法吗？如何将新语法应用于atzero信号？

Answer 1

你必须在课堂上声明你实施或继承的新信号;

class ZeroSpinBox (QSpinBox):
    atzero = Signal(int)
    .
    .

然后,你可以用新式信号调用它.用于发射信号;

        self.emit(SIGNAL("atzero(int)"), self.zeros)

改成

        self.atzero.emit(self.zeros)

用于连接信号;

         self.connect(zerospinbox, SIGNAL("atzero(int)"), self.announce)

改成

         zerospinbox.atzero.connect(self.announce)

您也可以阅读本文档以获取更多信息.

实现代码示例(PyQt4也是相同的PySide,不同的是名称Signal&pyqtSignal);

import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *

class ZeroSpinBox(QSpinBox):
    atzero = pyqtSignal(int)

    zeros = 0

    def __init__(self):
        super(ZeroSpinBox, self).__init__()
        self.valueChanged.connect(self.checkzero)

    def checkzero(self):
        if self.value() == 0:
            self.zeros += 1
#             self.emit(SIGNAL("atzero(int)"), self.zeros)
            self.atzero.emit(self.zeros)



class Form(QDialog):

    def __init__(self):
        super(Form, self).__init__()

        dial = QDial()
        dial.setNotchesVisible(True)
        zerospinbox = ZeroSpinBox()
        layout = QHBoxLayout()
        layout.addWidget(dial)
        layout.addWidget(zerospinbox)
        self.setLayout(layout)

        dial.valueChanged.connect(zerospinbox.setValue)
        zerospinbox.valueChanged.connect(dial.setValue)
        zerospinbox.atzero.connect(self.announce)
#         self.connect(zerospinbox, SIGNAL("atzero(int)"), self.announce)

        self.setWindowTitle("Signals")

    def announce(self, zeros):
        print("zerospinbox has been at zero " + str(zeros) + " times.")



app = QApplication(sys.argv)
form = Form()
form.show()
app.exec_()