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    <p>The reason it is not working is because the controller class is being garbage collected before you can ever click anything for it.</p> <p>When you set view.clicked = self.clicked, what you're actually doing is making one of the objects from the controller persist on the view object so it never gets cleaned up - which isn't really the solution.</p> <p>If you store your controller to a variable, it will protect it from collection.</p> <p>So if you change your code above to read:</p> <pre><code>ctrl = TestViewController(view) </code></pre> <p>You'll be all set.</p> <p>That being said - what exactly you are trying to do here, I am not sure...it seems you're trying to setup an MVC system for Qt - but Qt already has a pretty good system for that using the Qt Designer to separate the interface components into UI (view/template) files from controller logic (QWidget subclasses). Again, I don't know what you are trying to do and this may be a dumb down version of it, but I'd recommend making it all one class like so:</p> <pre><code>from PyQt4 import QtGui import sys class TestView(QtGui.QWidget): def __init__(self): super(TestView, self).__init__() self.initUI() def initUI(self): self.btn = QtGui.QPushButton('Button', self) self.btn.resize(self.btn.sizeHint()) self.btn.move(50, 50) self.btn.clicked.connect(self.buttonClicked) def buttonClicked(self): print 'clicked' def main(): app = QtGui.QApplication(sys.argv) view = TestView() view.show() app.exec_() if __name__ == '__main__': main() </code></pre> <p><strong>Edit: Clarifying the MVC of Qt</strong></p> <p>So this above example doesn't actually load the ui dynamically and create a controller/view separation. Its a bit hard to show on here. Best to work through some Qt/Designer based examples/tutorials - I have one here <a href="http://bitesofcode.blogspot.com/2011/10/introduction-to-designer.html" rel="nofollow">http://bitesofcode.blogspot.com/2011/10/introduction-to-designer.html</a> but many can be found online.</p> <p>The short answer is, your loadUi method can be replace with a PyQt4.uic dynamic load (and there are a number of different ways to set that up) such that your code ultimately reads something like this:</p> <pre><code>from PyQt4 import QtGui import PyQt4.uic import sys class TestController(QtGui.QWidget): def __init__(self): super(TestController, self).__init__() # load view uifile = '/path/to/some/widget.ui' PyQt4.uic.loadUi(uifile, self) # create connections (assuming there is a widget called 'btn' that is loaded) self.btn.clicked.connect(self.buttonClicked) def buttonClicked(self): print 'clicked' def main(): app = QtGui.QApplication(sys.argv) view = TestController() view.show() app.exec_() if __name__ == '__main__': main() </code></pre> <p><strong>Edit 2: Storing UI references</strong></p> <p>If it is easier to visualize this concept, you Can also store a reference to the generated UI object:</p> <pre><code>from PyQt4 import QtGui import PyQt4.uic import sys class TestController(QtGui.QWidget): def __init__(self): super(TestController, self).__init__() # load a view from an external template uifile = '/path/to/some/widget.ui' self.ui = PyQt4.uic.loadUi(uifile, self) # create connections (assuming there is a widget called 'btn' that is loaded) self.ui.btn.clicked.connect(self.buttonClicked) def buttonClicked(self): print 'clicked' def main(): app = QtGui.QApplication(sys.argv) view = TestController() view.show() app.exec_() if __name__ == '__main__': main() </code></pre>
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    1. POHow to connect a signal from the controller in PyQt4? (iOS like MVC structure in PyQt4)
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    1. POHow to connect a signal from the controller in PyQt4? (iOS like MVC structure in PyQt4)
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    1. COThe "assign controller to a variable" part is nice! Although, I would like to point out that the second part of your answer seems a bit contradictory. First of all, that is just a working example of what I'm trying to achieve. Second, you recommend the use of QtDesigner to separate View from the logic but then you show an example where all the elements of the program are in a single class. Notice that, in my example, the `TestView` class contains only UI elements and not a single line of "logic". The next step would be to forward the "clicked" call to the Model's API through the controller.
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    2. COYea, you're right - I didn't actually change your code at all, displaying how to use designer on here isn't as easy. Here's a tutorial: http://bitesofcode.blogspot.com/2011/10/introduction-to-designer.html
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    3. CORight, I get your point. But since your connections are made inside the view, it would have to have a reference to its controller object, correct? That could be solved by making the connections inside the controller, which would be the glue between view and model.
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