Ember CLI + HTMLBars -- Passing Parameters to a Helper

Question

I'm trying to pass a parameter from my HTMLBars template to a Helper.

As per the documentation, I've created a helper and explicitly registered the helper:

export default Ember.HTMLBars.makeBoundHelper('is-foo', function(value, options) {
   console.log("value: "+value);
});

But I get an error "Error: Assertion Failed: makeBoundHelper generated helpers do not support use with blocks"

So I've tried using Ember.HTMLBars.helper and Ember.HTMLBars.registerHelper as suggested here but I get errors "TypeError: Ember.default.HTMLBars.helper is not a function"

If I don't reigster the helper explicitly:

export default function(value, options) {
   console.log("value: "+value);
};

Then I can pass a parameter, but it doesn't get resolved and logs out the literal text of what I passed.

So I tried the solution outlined here but it doesn't seem to work with CLI

The result I want is for a component to be dynamically selected based on the value of the parameter I send to the helper. My HTMLBars code looks like:

{{#each foo in model}}
  {{is-foo parameter}}
    {{a-component}}
  {{else}}
    {{another-component}}
  {{/is-foo}}
{{/each}}

I'm not sure what to do next. Any help is appreciated.

with CLI use `ember g helper foo`. It will create a foo helper for you. Then you can look at its code to see how you can make your own manually. — Grapho, Apr 22 '15 at 13:46
Thank you for the response! I generated a helper with CLI, but it also creates a bound helper that I can't use with blocks. Basically I need a way to conditionally choose a component from my template, but I can't find any way to get it working. — TheCompiler, Apr 22 '15 at 14:14
Since: "The result I want is for a component to be dynamically selected based on the value of the parameter I send to the helper." possible duplicate of [How to include a component from a controller in ember](http://stackoverflow.com/questions/29777886/how-to-include-a-component-from-a-controller-in-ember) — givanse, Apr 22 '15 at 18:06

Hasib Mahmud · Accepted Answer · 2015-04-23T15:08:51.053

0

Do something like this in Ember CLI project, because helper file name is the helper name

export default Ember.HTMLBars.makeBoundHelper(function(value, options) {

instead of

export default Ember.HTMLBars.makeBoundHelper('is-foo', function(value, options) {

Edit

Upon @TheCompiler 's request here is the suggestion as an answer.

Do something like in HTMLBars

{{if is_parameter}}
  {{a-component}}
{{else}}
  {{another-component}}
{{/if}}

In Controller or Component the computed parameter property

is_parameter: function () {
  var pm = this.get('parameter');

  return (your condition for `pm`)? true : false;
}.property('parameter')

edited Apr 23 '15 at 15:08

answered Apr 22 '15 at 15:42

Hasib Mahmud

806
1
10
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Thanks, but it still gives me the error "Error: Assertion Failed: makeBoundHelper generated helpers do not support use with blocks". I just don't understand how to get around this. I want to dynamically choose a component from my template based on a parameter value, but how am I supposed to do that when I can't use conditions with helpers? – TheCompiler Apr 22 '15 at 16:07
@TheCompiler You should use computed properties as if conditionals, not Helpers. – Hasib Mahmud Apr 23 '15 at 13:50
Yeah, that's what I ended up doing. If you want to make this suggestion a new answer I'll mark it as accepted. – TheCompiler Apr 23 '15 at 14:32
When passing multiple parameters, those are given as array, so that you can read them as following `export default Ember.HTMLBars.makeBoundHelper(function(parameter, options) {var param1=parameter[0];var param2=parameter[1];console.log("p1:"+param1+" p2:"+param2);});` – L-Ray May 31 '15 at 13:08

score 0 · Answer 2 · edited May 23 '17 at 12:22

0

The behavior that you want is achieved in this answer.

If you would like to know how the component helper is implemented you can check its source code here: helpers/component.js (currently line 63)

edited May 23 '17 at 12:22

Community

1
1

answered Apr 22 '15 at 18:15

givanse

14,503
8
51
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Ember CLI + HTMLBars -- Passing Parameters to a Helper

2 Answers2