Pipe all keyboard commands automatically to an embedded mplayer instance when a modifier key is pressed in pyqt4

Question

This is a follow up question to this answer: https://stackoverflow.com/a/11939294/406686:

Consider the following code, which embeds mplayer in a QWidget. The problem is that it doesn't react to any mplayer keyboard shortcuts such as right arrow for seek forward and so on.

It's clear that I can reimplement every shortcut manually. However is there a way to pipe all keyboard sequences automatically to mplayer as long as a modifier key, say ALT or Win-Key is pressed?

For example: Press ALT + → = seek forward...

import mpylayer
from PyQt4 import QtGui, QtCore

class Window(QtGui.QWidget):
    def __init__(self):
        QtGui.QWidget.__init__(self)
        self.container = QtGui.QWidget(self)
        self.container.setStyleSheet('background: black')
        self.button = QtGui.QPushButton('Open', self)
        self.button.clicked.connect(self.handleButton)
        layout = QtGui.QVBoxLayout(self)
        layout.addWidget(self.container)
        layout.addWidget(self.button)
        self.mplayer = mpylayer.MPlayerControl(
            'mplayer', ['-wid', str(self.container.winId())])

    def handleButton(self):
        path = QtGui.QFileDialog.getOpenFileName()
        if not path.isEmpty():
            self.mplayer.loadfile(unicode(path))

if __name__ == '__main__':

    import sys
    app = QtGui.QApplication(sys.argv)
    window = Window()
    window.resize(640, 480)
    window.show()
    sys.exit(app.exec_())

score 1 · Answer 1 · edited Jul 02 '14 at 21:36

1

I am not sure, if I got your problem right. You could easily add the keyPressEvent and keyReleaseEvent methods to your Window Class:

class Window(QtGui.QWidget):
    def __init__(self):
        # same code as above
        self.setFocus()
        self.__modifier_pressed = False

    def keyPressEvent(self, event):
        if event.key() == QtCore.Qt.Key_Alt:
            self.__modifier_pressed = True
        elif self.__modifier_pressed:
            self.mplayer.run_command("key_down_event", event.nativeVirtualKey())

    def keyReleaseEvent(self, event):
        if event.key() == QtCore.Qt.Key_Alt:
            self.__modifier_pressed = False

This example would only work with Modifier+ONE other key. If you also need this for more complex shortcuts, such as Alt+Ctrl+Shift+→, you might need lists to save the currently pressed keys, but the basic idea should be clear.

On my computer, the pressed key of python and the received one from mplayer are different, but I use a very uncommon keyboard layout (Neo-Layout), so this might be the reason for this.

edited Jul 02 '14 at 21:36

xav

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answered Jan 24 '13 at 11:06

Sebastian Werk

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Thanks, but it doesn't work without error messages. If I print something before the line `self.__modifier_pressed = True` it is printed out, when the modifier key is pressed, but if I print something before `self.mplayer.run_command("key_down_event", key)` nothing happens, so it seems that the elif part never get's executed... – student Jan 25 '13 at 05:43
In general it should work when holding the “Alt”-Key and then pressing another key. I just realized, that there is a general problem with the arrow keys. As a workaround, I added self.setFocus() to the init-method, then all keyPressEvents get activated. – Sebastian Werk Jan 25 '13 at 07:12
1

I just found out, that event.nativeVirtualKey() may send the right key to mplayer, unfortunatly this does not work for arrow keys. Probably, they need to get converted manually to the key code required by mplayer. – Sebastian Werk Jan 25 '13 at 07:32
Thanks, this works except of the arrow keys and space (which would be important). Would be great if you have an idea how to solve this. Nevertheless I give you the bounty points! – student Jan 25 '13 at 16:19

Pipe all keyboard commands automatically to an embedded mplayer instance when a modifier key is pressed in pyqt4

1 Answers1