Debug QT Signals

debug_qtsignals.py

import functools
import inspect
import log

from PyQt4 import QtCore
from PyQt4 import QtGui


logger = log.getLogger(__name__)


def log_manual_slot(f):
    """
    Decorate functions that are passed to the signal 'connect' method.
    
    Example:
        >>> mysignal.connect(log_manual_slot(myslot))
    """
    @functools.wrap(f)
    def wrapper(*args, **kwargs):
        signal_name = inspect.stack()[1][0].f_code.co_names[-2]
        logger.debug('{0}{1} emitted by {2} and picked up by {3}'.format(
            signal_name,
            args,
            str(inspect.stack()[1][3]),
            f.__name__))
        return f(*args)
    return wrapper
    
def log_automatic_slot(f):
    """ Decorate 'pyqtSlot' decorated methods. """
    @functools.wrap(f)
    def wrapper(*args, **kwargs):
        _, signal_name = f.__name__.rsplit('_', 1)
        logger.debug('{0}{1} emitted by {2} and picked up by {3}'.format(
            signal_name,
            args[1:],
            str(args[0].sender()),
            f.__name__))
        return f(*args)
    return wrapper


class MainWindow(QtGui.QMainWindow):

    updated = QtCore.pyqtSignal(str)

    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)

        self.button = QtGui.QPushButton('My button', self)
        self.button.setObjectName('mybutton')

        QtCore.QMetaObject.connectSlotsByName(self)

    @log_automatic_slot
    @QtCore.pyqtSlot()
    def on_mybutton_clicked(self):
        self.updated.emit('hello, world!')


def update_recv(data):
    1 + 1

def update_recv2(data):
    1 + 1
    

if __name__ == '__main__':
    import sys

    app = QtGui.QApplication([])

    view = MainWindow()
    view.updated.connect(log_manual_slot(update_recv))
    view.updated.connect(log_manual_slot(update_recv2))
    view.show()

    app.exec_()