Meteor: Call template helper from other template

0
votes

I have two templates and I've defined JavaScript helpers and events to go with each. When a button is clicked in template A, one of the things I want to do is call a helper function for template B which will change what's displayed on the screen. Is this possible?

If it's not possible, I'd instead like to reload template B.

How can I do either of these? Do I use Tracker.autorun? Reactive variables? Ideally I would do, inside an event function for template A,

    B.helpers.call("helperFunctionFromTemplateB");
1
meteor

1 Answers

2
votes

There are a lot of solutions to what I think you want to achieve, but the answer really depends on context.

  1. If template A is a child template of B:
    1. You can pass a reference to a ReactiveVar in the parent template down to the child template's data context and modify it using {{>childTemplate reactiveVar=reactiveVar}} where reactiveVar is a helper in the parent template that returns the reference to the reactive variable
    2. If the thing you want to change is in the parent's data context, you can use Template.parentData(n) where nis the amount of levels you want to jump up. While modifying the parent's data may not immediately seem reactive, you can make the data prop reactive by accessing it via Template.currentData()
  2. Use some kind of globally accessible state. The most common answer would probably be to use the Session package and use Session.get('var') and Session.set('var', val).
  3. Use an event emitter. This approach gets +'s for decoupling and reusability, but it's also potentially heavy handed if you only need to modify this variable in one place from one source (i.e. your requirements are simple)
  4. Meteor 1.3 - If you want to make references to your reactive data in multiple places but don't want to create a global like Session, use a ReactiveVar or Reactive Dict (closer to session), create your variable where it makes sense, export it, and import it in your templates/anywhere else to be used.

There's a lot of other solutions, these are just the first that come to mind. If you provide more specific context, I'll provide a code sample of what I think's best and explain why. :)