Polymer function call with parameters

Question

This seems like a very simple one, but somehow I am not sure how to do it. I want to send data to a Polymer component with the "core-collapse-open" event but this is not working:

<core-collapse on-core-collapse-open="{{loadDetails(data)}}">
{{data.Title}}
...

When I use the above code, the loadDetails function in polymer is not hitting.

Polymer('custom-item', {
        data: {},
        ready: function () {
        },   
        loadDetails: function (e, details, sender) {
            debugger;
        }
    });

If I am not using the function syntax in the declarative syntax(as below), the loadDetails function hits.

<core-collapse on-core-collapse-open="{{loadDetails}}">
{{data.Title}}
...

How can I send parameters in events.

This doesn't look like to be related to Dart. Is there any reason you added the `dart-polymer` tag? — Günter Zöchbauer, Jan 26 '15 at 08:42
I was not sure if this was related to Dart. I will remove that now. — Sumesh Kuttan, Jan 27 '15 at 07:05
The Polymer 1.x way to do it: http://stackoverflow.com/questions/28210278/polymer-event-parameters-on-repeat/31749033#31749033 — adam, Jul 31 '15 at 14:49

score 0 · Answer 1 · answered Jan 23 '15 at 07:26

on-core-collapse-open="{{loadDetails(data)}}"

This means: execute loadDetails(data) and whatever the return value of this is will be bound as the event handler. Not what you want.

Also, the event handler function already receives parameters: the event object. You cannot pass it additional parameters. If the data you want to pass refers to your this.data attribute: the loadDetails function already has access to it in the form of this.data, so you don't need to pass it.

If you're trying to use the same handler function for two different events and pass additional parameters with each individual event: traditionally you'd do that with an anonymous function wrapper, and that's simply not possible using the declarative syntax.

data is not this.data. So, I really needed that additional parameters. Let me think if there is any workaround. — Sumesh Kuttan, Jan 23 '15 at 13:31

score 0 · Answer 2 · edited May 23 '17 at 12:15

0

You can bind data to an attribute of core-collapse and then access the data using the target argument of the event handler or the target property of the event argument or alternatively if data is the model of the element anyway just access the TemplateInstance (see full example at https://stackoverflow.com/a/24530099/217408)

edited May 23 '17 at 12:15

Community

1
1

answered Jan 26 '15 at 08:40

Günter Zöchbauer

623,577
216
2,003
1,567

score 0 · Accepted Answer · edited May 23 '17 at 11:44

0

I got the answer from my another post. Even though I posted for different context, I understand I can use the same. Thanks Gunter for reply on that thread.

Polymer event parameters on repeat

edited May 23 '17 at 11:44

Community

1
1

answered Jan 29 '15 at 10:42

Sumesh Kuttan

1,333
1
17
40

Polymer function call with parameters

3 Answers3

Linked