[Interest] Qml bindings with javascript library functions in them

[Josh Faust]

On Thu, Jun 13, 2013 at 11:41 AM, Alan Alpert <416365416c at gmail.com> wrote:

> Bindings do not update when a purely JS variable changes, it can only
> respond to changes in QML properties. You could bind to something like
>  stateObject.value, and still be able to use
> JS.setValue(stateObject.value + 1) if you wanted. But without going
> through C++ though you couldn't make stateObject.value read-only to
> everything but the setValue function.
>

Ah, I had forgotten about the distinction between properties and JS
variables. That gave me an idea though, and it looks like it works. I can
pass a QML object into the javascript, and use a property from it:

var _GenerationObject;
var _LastGeneration;
var _Value;
function setGenerationObject(obj)
{
  _generationObject = obj;
}

function getValue()
{
  // Force re-evaluation if _GenerationObject.generation changes
  if (_GenerationObject.generation != _LastGeneration)
  {
    _LastGeneration = _GenerationObject.generation;
  }

  return _Value;
}

function setValue(val)
{
  _Value = val;
  ++ _GenerationObject.generation;
}

Now the only trick is getting that value set before anything else
constructs, but that should be solveable.

Thanks!

Josh
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