adjustments for dash 3 support

[BSd3v]

No description provided.

[BSd3v]

This is ran as dash 3, and passing:

https://github.com/plotly/dash-ag-grid/actions/runs/13117864371/job/36596481157

I'm going to revert the pinning of the dash 3 rc.

[AnnMarieW]

You can't get use loading_state in dash 3. Need to use

static contextType = window.dash_component_api.DashContext;

async loading() {
    while (this.context.isLoading()) {
        await wait(100);
    }
}

[BSd3v]

The loading isnt for supporting dash 3, its for support dash 2. As the alterations to dash 3 decreased the number of times the component is rerendered.

Also, this is a test to see if loading exists, and if so test it, if not, do nothing.

You can see an example here:

plotly/dash#3066 (comment)

---

Essentially, there is no equivalent to the Previous Loading state as everything in Dash 3 is for the current state. However, because Dash is no longer passing this data back to the component (forcing a rerender) there is no reason to check the previous state.

This was mainly to combat things like selectedRows and columnState coming from the Dash server being overwritten by the grid component.

Dash 2:

• callback triggered to update selectedRows or columnState
• dash adjusts the state of loading_state to trigger the props.
• When it hits this check, the previous state of loading_state was not loading, therefore it passes over this section and doesnt try to perform anything with the props. Freezing the component in time until the callback is completely done loading
• the loading_state gets flipped again
• now props that were adjusted in the callback are realized in the grid

Dash 3:

• no flipping of the prop for loading state
• assumes all readjustments to the grid coming through are to be realized immediately unless other catches happen (selections paused, or data updated)