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javascriptjsondatepolymerdayofweek

Polymer print part of a JSON object from String

I was wondering how to print a part of my JSON object in Polymer without it printing just the template code I wrote.

My JSON object looks like this:

weekDagenVertalingen:{
  type: Object,
  value:
  {
    'MONDAY':'Maandag',
    'TUESDAY':'Dinsdag',
    'WEDNESDAY':'Woensdag',
    'THURSDAY':'Donderdag',
    'FRIDAY':'Vrijdag',
    'SATURDAY':'Zaterdag',
    'SUNDAY':'Zondag'
  }
}

In javascript I'm able to do this:

var day = 'MONDAY';
console.log(weekDagenVertalingen[day]);

This Javascript code prints out: Maandag

But for some reason when trying this:

{{weekDagenVertalingen[item.day]}}

It literally prints out this: {{weekDagenVertalingen[item.day]}} instead of the actual value of the JSON object.

I was thinking about getting the string this way:

{{weekDagenVertalingen.item.day}}

But I have no clue how to tell Polymer item.day is a value.

What am I doing wrong here?

Solution

  • It's been a while since I've used Polymer, but I believe that you want a computed binding. Computed bindings only work one way (host to target).

    ...
<span>[[_getDay(item])]]</span>
...
<script>
  Polymer({
    ...
    _getDay: function(item) {
      return this.weekDagenVertalingen[item.day];
    }
  })
</script>

    see: https://www.polymer-project.org/1.0/docs/devguide/data-binding (scroll down until you see the computed bindings section)