Support for Inheritance

[stlehmann]

Currently the mapper is not working with inherited QWidget classes. Do you have any plans for fixing this?

Here is my Traceback:

Traceback (most recent call last):
  File "C:/Users/Lehmann/data/python34/ustempctrl/run_ustempctrl.pyw", line 14, in <module>
    w = CtrlTestGui()
  File "C:\Users\Lehmann\data\python34\ustempctrl\ustempctrl\mainwindow.py", line 49, in __init__
    self.plotsettings = PlotSettingsWidget(self)
  File "C:\Users\Lehmann\data\python34\ustempctrl\ustempctrl\plotsettings.py", line 38, in __init__
    self.settings.add_handler('plot/xmin', self.xminSpinBox)
  File "C:\Users\Lehmann\data\python34\pyqtconfig\pyqtconfig\config.py", line 800, in add_handler
    assert False, "No handler-functions available for this widget type (%s)" % type(handler).__name__
AssertionError: No handler-functions available for this widget type (CoordSpinBox)

[stlehmann]

Not so sure if it is appreciated but I made a pull request for this issue.

[mfitzp]

Very much appreciated 👍 I just need to find time to sit down and work through the PRs.

From what I've seen I don't imagine having any problems merging any of them but I need test against PyQt4, PySide and on different platforms (Windows, Linux) before accepting. They all do slightly weird things with the input/output of QSettings and it can cause issues.

[mfitzp]

Specific to this bug, the normal way I've dealt with this is to write custom handlers for the subclasses (you can pass them in when creating the manager). I have custom widgets that override signals and return different types, so it will need to ensure that the most specific possible handler is used. Perhaps test by type with fallback to isinstance?

[stlehmann]

Perhaps test by type with fallback to isinstance?

I agree with you here. isinstance would return True for the base class and the inherited class and there is no way I know to tell which class is the more specific one. To check with type first would avoid this pitfall.

[stlehmann]

Alright, I modified the code that now first the exact type is checked with type==. If there is no match another comparison is done with isinstance. I also made some tests for this use case.