DataGrid pagination_click event

[stenci]

I have a problem with the data_grid.set_event_handler('pagination_click', self.pagination_click).

I am able to get my handler to run, but I can't prevent the default one from running.

I would like to e.preventDefault(), so I can add items to the list when we are approaching the end before showing the next page.

I tried to return True on my event handler, but didn't help. My handler runs and the page is loaded anyway.

Any idea about how to get e.preventDefault() to work, or something equivalent?

[s-cork]

e.preventDefault() is typically used to prevent default browser behaviour.
But anvil's own event listeners aren't going to respect that.

Instead you'd need to be able to call e.stopPropagation() to stop the event from propagating to anvil's handlers.

Locally you can try copying the augment module to try out some changes
Use your local version rather than the anvil-extras one

Then adding this to line 215 to be

def _wrap_js_event(handler):
    def wrapper(e):
        handler(original_event=e)

    return wrapper

Then in your handler

    def my_data_grid_click_handler(self, **event_args):
        original_event = event_args["original_event"]
        original_event.stopPropagation() # stop this event from propagating
        # original_event.stopImmediatePropagation() # might be required try this if the above doesnt work
        ... # rest of function

If that works we can look to merge it upstream

[stenci]

Hi Stu,
Thank you for the reply, but I tried with your suggestions and it didn't work.

So I am giving up with managing the pagination events.

Instead I created a little DynamicIterator class that works with a DataGrid just like the SearchIterator. It lazily loads items in chunks, which is what I wanted to do with the pagination events anyway.

I will publish this little class in the forum in a few days, after a little real world testing.