Array in Data View Filter

I have some javascript that adds to an array like so…

onValueChanged(e) {
        new_array = dmx.parse("array_categories");
        new_array.items = [];
        new_array.count = 0;
        for (item of e.value) {
            new_array.items.push(item);
        }
        console.log(dmx.parse("array_categories.items"));
    },

That works fine and outputs the array as expected.

However, it doesn’t dynamically update the value of the array on the page. I’m ultimately using it to filter a data view but have tried putting it into a text value for testing as the filter wasn’t working so I have

<h1 dmx-text="array_categories.items"></h1>

and the array itself is like this…
<dmx-array id="array_categories" dmx-bind:items="[1,3]"></dmx-array>

That outputs

But the values don’t change when the output of array_categories changes.

Any ideas?