René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"getopenfilename does not block when when using ipython inputhook/start_event_loop","articleBody":"This is very similar to #2380. However, since that issue, and related ones, are all closed, I'm presenting this similar issue, which has already been posted on [Stack Overflow](http://stackoverflow.com/questions/27625394/getopenfilename-does-not-block-when-when-using-ipython-inputhook-start-event-loo)\n\nNote: If not using the native dialog option, all works fine. This is just when using the native dialog.\n\nWhen trying to run Qt in iPython, using the inputhook and start_event_loop, to create non-blocking app, the function PyQt4.QtGui.QFileDialog.getOpenFileName does not allow for input. It pops up and immediately closes.\n\nThe code below demonstrates the behavior. If run through _main(), which starts the Qt eventloop normally, all works fine. Both the generic Dialog and FileDialog operate as expected.\n\nHowever, when run as\n\n```\n$ ipython\nIn [1]: import ipython_nonblock_example as nb\nIn [2]: nb_instance = nb.start_gui(nb.Example)\n```\n\nthe Dialog works as expected. But the FileDialog does the open/close behavior.\nVersions are: IPython 2.3.1, Qt 4.8, PyQt4 4.11.1,Python 2.7.5\n\nFile ipython_nonblock_example.py\n\n``` python\nimport sys\nfrom PyQt4 import QtGui, QtCore\n\nclass Example(QtGui.QMainWindow):\n    def __init__(self):\n        super(Example, self).__init__()\n\n        self.initUI()\n\n    def initUI(self):\n        self.btn = QtGui.QPushButton('Dialog', self)\n        self.btn.move(20, 20)\n        self.btn.clicked.connect(self.showDialog)\n\n        self.btn2 = QtGui.QPushButton('File', self)\n        self.btn2.move(20,50)\n        self.btn2.clicked.connect(self.showFile)\n\n        self.le = QtGui.QLineEdit(self)\n        self.le.move(130, 22)\n\n        self.setGeometry(300, 300, 290, 150)\n        self.setWindowTitle('Input dialog')\n        self.show()\n\n    def showDialog(self):\n        text, ok = QtGui.QInputDialog.getText(self, 'Input Dialog',\n            'Enter your name:')\n\n        if ok:\n            self.le.setText(str(text))\n\n    def showFile(self):\n        file_name = str(QtGui.QFileDialog.getOpenFileName(parent=self, caption='Open file'))\n\n        if file_name:\n            self.le.setText(str(file_name))\n\ndef start_gui(ui, block=False):\n    try:\n        if not block \u0026 __IPYTHON__:\n            from IPython.lib.inputhook import enable_gui\n            app = enable_gui('qt4')\n        else:\n            raise ImportError\n    except (ImportError, NameError):\n        app = QtCore.QCoreApplication.instance()\n    if app is None:\n        app = QtGui.QApplication(sys.argv)\n\n    ui_instance = ui()\n\n    try:\n        from IPython.lib.guisupport import start_event_loop_qt4\n        start_event_loop_qt4(app)\n        return ui_instance\n    except ImportError:\n        app.exec_()\n\ndef _main():\n    start_gui(Example, block=True)\n\nif __name__ == '__main__':\n    _main()\n```\n","author":{"url":"https://github.com/triccare","@type":"Person","name":"triccare"},"datePublished":"2014-12-23T22:13:22.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":11},"url":"https://github.com/7301/ipython/issues/7301"}