how to populate bind options from data source (not manually)?

I’ve modified the stocks example with a drop-down box to select a company, like this: https://vega.github.io/editor/#/gist/vega/mattijn/a25b9ba41a775cf128d1472cd3e44253 (btw, great update to the new editor!)

But now I’ve to declare the bind > options manually ("GOOG", "MSFT", etc) I was hoping I could make use of a Collect Transform to get all (unique) values from a data source, which I can use in the bind signal. But this seems not be supported?

[Squaredj]

This would be really nice to have: for example to fill a “bind select” with items straight from the data itself. Any changes in the current Vega-release that would make this possible yet?

[aodhan-domhnaill]

vega-parser constructs the Spec Scope with bindings that get used in View initialization.

My test case dumps,

(index):119 TypeError: param.options.forEach is not a function
    at select (vega.js:31121)
    at generate (vega.js:31069)
    at bind$1 (vega.js:31034)
    at vega.js:31293
    at Array.forEach (<anonymous>)
    at View.initialize$1 [as initialize] (vega.js:31292)
    at new View (vega.js:34768)

The bind elements are constructed here, which leads us to the forEach call we see in the stack trace

Seems like I could use view.data (see also) to get at the data.

So seems like I just need to stick something like below right here,

if (param.options && !Array.isArray(param.options)) {
  if (param.options.field) {
    param.options = view.data(param.options.name).map(x => x[param.options.field]);
  } else {
    param.options = view.data(param.options.name);
  }
}

I’ll test it out now.