Binding to computed functions: onBind callback called twice. If computed function has no setter , "... is not a function" exception thrown about jsviews HOT 6 CLOSED

Thank you very much for posting this. It's a good catch. I'll need to do some investigation... I'll let you know...

from jsviews.

Here is a potential update that should address your issues. Can you test that it works correctly for you?

jsviews.zip

Incidentally, your example is data-linking to util1(), as if it was a computed observable, but for the binding to work, it needs an associated setter function. See https://www.jsviews.com/#computed@getset.

For example, you could write:

let tmpl = $.templates("{^{tag1 Prop1() param1=~hlp.util1(1) /}}");
let utils = {hlp: {
    util1: function(a) {
      return this._util1;
    },
  _util1: "initUtil1"
}};
utils.hlp.util1.set = function(val) {
  this._util1 = val;
};
tmpl.link("#text1", m, utils); 

If you provide a setter, as above, the "view.ctxPrm(...) is not a function" exception will not be thrown.

But with the jsviews.js update provided there will no longer be any exception, even if you don't provide a setter. (Though of course two-way binding will not work unless there is a setter defined...)

Let me know if this works for you...

from jsviews.

Thank you, Boris. The update resolves both throwing the exception and double onBind event.

from jsviews.

Thanks for confirming. I except to include this in the upcoming version 1.0.10.

from jsviews.

The fix concerns two issues:

• Binding to a computed function with no getter, such as <input data-link="name()"/> with name.set undefined leads to an exception "name is not a function".
• Tag two-way binding to a computed observable, such as {^{mytag name()/}} can trigger onBind callback twice.

from jsviews.

Fixed in release v1.0.10

from jsviews.