Iron.controller is not reactive in all cases

[mitar]

If you have two routes with the same template set, then Iron.controller().getParams() is not rerun if the URL (and thus params) change. Maybe the problem is that getParams is not reactive. So if I use the same template but different URLs for different params, template helper is not called again for new params.

See reproduction: https://github.com/mitar/ironrouter-issue1232

[kontur]

Ran into what I believe to be the same issue with two routes that use the same template, but one of them passes in a data object, when the other runs without. The render functions are called, the template is just not re-rendered on the second route.

Seems rather unlikely that simply having the same template for two routes wouldn't trigger a new render, but can it be?

Is there any way to force a route's template to re-rendered, as a work around to be used?

[kontur]

For now I used a reactive var / session variable in the route controller and execute the template rendered function when it changes by accessing it in the template rendered function. :/

Anybody with more insight to iron router got an idea where to start with this issue?

[mcrayne]

Edit : don't pay any attention to my response below, though learning more about the Tracker module was helpful, my problem was I needed to put the function to update data in the template in helpers and not in the onRendered() callback. I was confused because it would work intermittently and I thought that since the router_controller was rendering the template it would refresh for each new /:id url passed. It doesn't. Anyways, moving the lookup and load logic into the template.myTemplate.helpers() there were no more problems.

I am still fairly new so this may not be best pattern, but, after searching everywhere for a solution to this, it does appear that you DO need to set a session variable as @kontur states - but, under 1.0.4 I could not get the onRendered(...) to run again even though I referenced the Session variable in the callback and could verify it was changing, though not triggering a new rendering.

I was only able to solve that by wrapping the callback with Tracker.autorun

 onRendered( function () {
     Tracker.autorun( function() {
        Session.get('myVar') ...   })
});

It makes sense when you watch how the events are raised (onRendered for example) but it would be nice not to have to wrap the callback and just count on the reactive Session variable.

[kontur]

I tried look into this a bit more, but I just lack insight into iron router :/ Can't even tell if the component in the wrong here is router, controller or layout. Any input? 👍

[niranjans]

+1. Have the same issue. When I do a Router.go() within the same template but with different query params, the params object does not seem to be reactive.

[keviniamburg]

+1

[kokjinsam]

+1

[romiohasan]

+1

[ciclopes]

Well, I believe I was having kinda the same issue.
Here is what I've done to force a template update upon a same route params change:

## router.coffee
Router.route '/profile/:_id',
  name: 'profile'
  action: ->
    Session.set 'profileId', @params._id
    @render 'profile'

## profile.coffee
Template.profile.onCreated ->
  @user = new ReactiveVar
  template = @

  @autorun ->
    template.subscription = template.subscribe 'profile', Session.get 'profileId'

    if template.subscription.ready()
      template.user.set Meteor.users.findOne _id: Session.get 'profileId'
    else
      console.log 'Profile subscription is not ready'

Template.profile.helpers
  user: -> Template.instance().user.get()

## profile.html
<template name="profile">
  {{#if user}}
    {{#with user.profile}}
      <span class="first-name">{{firstName}}</span>
      <span class="last-name">{{lastName}}</span>
    {{/with}}
  {{else}}
    <span class="warning">User not found.</span>
  {{/if}}
</template>

The main point here is the Session variable inside the subscribe call, which in turn is in the autorun call (profile.coffe file). Since the Session variable is a reactive data source, the subscription will be updated as well as the template, causing the latter to be rerendered.