Binding to e.g. <input value=""> in 0.8

[Michael Bleigh]

I started trying to port firebase-element to 0.8 and got stuck on simple two-way binding to input values. Is two-way binding only supported via custom elements in 0.8? How would I do the equivalent of this in 0.5:

<firebase-element location="https://example.firebaseio.com/demo" data="{{data}}"></firebase-element>

<input value="{{data.name}}">

Or, if that ought to work properly can you take a look at this example and tell me what's wrong with it?

Cheers,

Michael Bleigh

[Michael Bleigh]

Oops, wrong link to the example. Should have been https://github.com/mbleigh/firebase-element/blob/0.8-preview/demos/firebase.html

[Aleks Totic]

firebase port is not straightforward. Firebase-element uses observers to detect changes for auto-save, and the observers are not used in 0.8. I would not start porting until I fully understand 0.8 data flow.

As for your question:

In 0.5, property binding used observers. Which was lovely, the model and the editor did not need to know anything about each other, everything just worked

In 0.8, property binding is implemented using custom events to broadcast poperty changes. Native tags like <input> do not broadcast these custom events. So, you'd have to do something like this:

<input on-change='handleChange'>

handleChange: function() {

    firebaseElement.setPath('data.name', this.$.input.value);

}

Which is a lot more verbose than it used to be. This area is still in a lot of flux.

Aleks

On Saturday, March 28, 2015 at 2:09:55 PM UTC-7, Michael Bleigh wrote:

[Justin Fagnani]

Hi Michael,

There's a branch of 0.8 where work is being done to let you specify an event that will trigger an update of a binding. This will let you make two-way bindings to native elements, and custom elements that don't follow Polymer's event firing and naming conventions.

I'm not 100% sure, but I think the syntax right now looks like this:

<input value="{{data.name::change}}">

where the "::change" part basically means "on 'change' events, read the 'value' property and write it to the binding"

Not sure when this will land in 0.8, probably soon. You can file an issue and we'll notify it when it's in.

Cheers!

  Justin

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