Source code for ibllib.misc.qt

"""PyQt5 helper functions."""
import logging
import sys
from functools import wraps

from PyQt5 import QtWidgets

_logger = logging.getLogger(__name__)




def get_main_window():
    """Get the Main window of a QT application."""
    app = QtWidgets.QApplication.instance()
    return [w for w in app.topLevelWidgets() if isinstance(w, QtWidgets.QMainWindow)][0]





def create_app():
    """Create a Qt application."""
    global QT_APP
    QT_APP = QtWidgets.QApplication.instance()
    if QT_APP is None:  # pragma: no cover
        QT_APP = QtWidgets.QApplication(sys.argv)
    return QT_APP





def require_qt(func):
    """Function decorator to specify that a function requires a Qt application.

    Use this decorator to specify that a function needs a running Qt application before it can run.
    An error is raised if that is not the case.
    """
    @wraps(func)
    def wrapped(*args, **kwargs):
        if not QtWidgets.QApplication.instance():
            _logger.warning('Creating a Qt application.')
            create_app()
        return func(*args, **kwargs)
    return wrapped





@require_qt
def run_app():  # pragma: no cover
    """Run the Qt application."""
    global QT_APP
    return QT_APP.exit(QT_APP.exec_())