Make sure PyQt5 is supported

[astrofrog]

To install in conda: http://stackoverflow.com/questions/25468397/using-anaconda-python-with-pyqt5

[astrofrog]

Notes here: https://wiki.qt.io/Transition_from_Qt_4.x_to_Qt5

[astrofrog]

Note that to get PyQt5 to work at all, I needed to do https://github.com/conda/conda-recipes/issues/385

[astrofrog]

Stuck on this very frustrating error:

glue/qt/widgets/mpl_widget.py:38: in wrapper
    result = func(*args, **kwargs)
glue/core/application_base.py:72: in new_data_viewer
    c = viewer_class(self._session)
glue/qt/widgets/histogram_widget.py:46: in __init__
    super(HistogramWidget, self).__init__(session, parent)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <glue.qt.widgets.histogram_widget.HistogramWidget object at 0x12f035180>
session = <glue.core.session.Session object at 0x12e99a4d0>, parent = None

    def __init__(self, session, parent=None):
        """
            :type session: :class:`~glue.core.Session`
            """
>       QMainWindow.__init__(self, parent)
E       TypeError: __init__() takes exactly 2 arguments (1 given)

Even though I am passing two arguments. However it's possible parent no longer takes None as an argument but that still wouldn't explain error message

[astrofrog]

So inverting the order of inheritance for DataViewer to:

class DataViewer(ViewerBase, QMainWindow):

fixed that issue, somehow. Not 100% I understand at this point.

[astrofrog]

Only two failing tests...

[astrofrog]

Need to set the following to get HiDPI icons:

app.setAttribute(QtCore.Qt.AA_UseHighDpiPixmaps);

[astrofrog]

Main to-dos:

• Move changes from glue.external.qt to qt_helpers
• Check how icons look on non-HiDPI display
• Get all tests passing
• Check that we don't break anything on PyQt4

[astrofrog]

The following will be required for Matplotlib icons to look good in PyQt5: matplotlib/matplotlib#5057

[ChrisBeaumont]

Does Qt5 not support this?

[astrofrog]

It does but I had to add a method now, see a few lines down.

[astrofrog]

There were issues with the existing PyQt5 packages for conda, so I made a Docker image in which to build my own: https://hub.docker.com/r/astrofrog/ubuntu-12.04-conda-pyqt5-builder/ - the conda package can be installed with conda install -c astrofrog pyqt5. Fingers crossed that it works.

[astrofrog]

[astrofrog]

Well, this took a while :-/

🎉

[ChrisBeaumont]

Nicely done!