We primarily just use dmx.app.data and dmx.parse only for all our custom JS needs.
Using App Connect with JavaScript Functions - this is one of the docs about using dmx in JS that I know of. Probably you have seen it too.
If you are trying to set some Wappler array named resize_data from JS, you can try this:
dmx.app.data.resize_data.items = resize_data;
resize_data on right is the JS array.