Pass data to a dynamic template - meteor

With meteor updates up to 0.8 my old code stopped working.
Handlebars.registerHelper('getTemplate', function(id, context) {
return Template[id](context);
});
<template name="main">
....
{{{getTemplate templateName context}}}
....
</template>
//somewhere in other template
Template.main.context = {name:value};
This way I was able to render a custom template with custom data. Now I can't find the way to pass context to the dynamic template. With blaze both templateName and context is undefined. Any advice?

Meteor >= 0.8.2
You can use the UI.dynamic helper render a template with a context which are both specified dynamically. For more details, check out this issue.
Meteor < 0.8.2
Both of these issues are addressed on this page in the meteor wiki.
Handlebars.registerHelper is now UI.registerHelper as seen here.
Examples of how to dynamically render templates are shown here.
update
Actually, given the requirements, a solution doesn't seem very obvious to me. If you are willing to use session variables to set the template name and context, AND only have one dynamic template in your main template. You could do something like this:
<body>
{{> main}}
</body>
<template name="main">
{{> getTemplate context}}
</template>
<template name="dogs">
<p>There are {{animals}} dogs!</p>
</template>
<template name="cats">
<p>There are {{animals}} cats!</p>
</template>
Session.setDefault('templateName', 'dogs');
Session.setDefault('templateContext', {animals: 10});
Template.main.getTemplate = function() {
return Template[Session.get('templateName')];
};
Template.main.context = function() {
return Session.get('templateContext');
};

This was brought up on the meteor-core list and #dgreensp, MDG core dev working on Blaze, opened Ticket #2007 - How to render a template to HTML with data so they definitely know about this and I'd expect a fix to land soon after 0.8.0.
He also included the following workaround:
var toHTMLWithData = function (kind, data) {
return UI.toHTML(kind.extend({data: function () { return data; }}));
};
The github ticket has further discussion and alternate code snippets that you may find useful.

Related

Meteor Iron:Router Template not Rendering

I have a main page which lists a few text items ("Ideas"), which are clickable links. Clicking on them should take you to a page where you can edit them. Here's my html:
<head>
<title>Ideas</title>
</head>
<body>
</body>
<template name="Ideas">
<ul>
{{#each ideas}}
{{> idea}}
{{/each}}
</ul>
</template>
<template name="idea">
<li>{{text}}</li>
</template>
<template name="ShowIdea">'
<div class="editable" contentEditable="true">{{text}}</div>
</template>
I've added Iron:Router to my project to allow for moving between the pages. Here's the javascript:
Ideas = new Mongo.Collection("ideas");
if (Meteor.isClient) {
Router.route('/', function() {
this.render('Ideas');
});
Router.route('/idea/:_id', function() {
var idea = Ideas.findOne({_id: this.params._id});
this.render('ShowIdea', {text: idea.text});
});
Template.Ideas.helpers({
ideas: function () {
return Ideas.find({});
}
});
}
I inserted a single idea to my Mongo DB using the Meteor Mongo command line tool. That single item shows up properly on my main page. Here's what the HTML looks like in my debugger for the main page:
<html>
<head>...</head>
<body>
<ul>
<li>
The first idea ever
</li>
</ul>
</body>
</html>
Clicking on that link takes me to a new page with an address of:
http://localhost:3000/idea/ObjectID(%22550b7da0a68cb03381840feb%22)
But nothing shows up on the page. In the debugger console I see this error message + stack trace, but it means nothing to me since it all seems to be pertaining to iron-router and meteor, not code which I actually wrote:
Exception in callback of async function: http://localhost:3000/Idea.js?2fd83048a1b04d74305beae2ff40f2ea7741d40d:10:44
boundNext#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:424:35
http://localhost:3000/packages/meteor.js?e53378596562e8922a6369c955bab1e047fa866b:978:27
onRerun#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:520:13
boundNext#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:424:35
http://localhost:3000/packages/meteor.js?e53378596562e8922a6369c955bab1e047fa866b:978:27
onRun#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:505:15
boundNext#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:424:35
http://localhost:3000/packages/meteor.js?e53378596562e8922a6369c955bab1e047fa866b:978:27
dispatch#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:448:7
_runRoute#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:543:17
dispatch#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:844:27
route#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:710:19
boundNext#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:424:35
http://localhost:3000/packages/meteor.js?e53378596562e8922a6369c955bab1e047fa866b:978:27
boundNext#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:371:18
http://localhost:3000/packages/meteor.js?e53378596562e8922a6369c955bab1e047fa866b:978:27
dispatch#http://localhost:3000/packages/iron_middleware-stack.js?0e0f6983a838a6516556b08e62894f89720e2c44:448:7
http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:390:21
_compute#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:308:36
Computation#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:224:18
autorun#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:499:34
http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:388:17
nonreactive#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:525:13
dispatch#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:387:19
dispatch#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:1688:22
onLocationChange#http://localhost:3000/packages/iron_router.js?a427868585af16bb88b7c9996b2449aebb8dbf51:1772:33
_compute#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:308:36
_recompute#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:322:22
flush#http://localhost:3000/packages/tracker.js?21f0f4306879f57e10ad3a97efe9ea521c5b5775:452:24
And then it ends with this warning message:
Route dispatch never rendered. Did you forget to call this.next() in an onBeforeAction?
I don't have an onBeforeAction (I'm not even sure what that is)... so I don't think that message pertains to me?
I just started using Meteor the other day and just added iron-router not 24 hours ago, so I'm a bit lost here. Any pointers on how I can debug and fix this would be great.
Two things need fixing:
When you insert documents from the shell they are assigned _id values which are mongo ObjectIDs, whereas meteor defaults to using strings. This explains the weird URL. To avoid this problem, it's generally best to initialize your data from the server. Here's an example:
if (Meteor.isServer) {
Meteor.startup(function() {
if (Ideas.find().count() === 0) {
Ideas.insert({text: 'feed the cat'});
}
});
}
Now after a $ meteor reset you will always start with one cat-related idea.
If you wish to pass a context to your template, you'll need to use the data attribute like so:
Router.route('/idea/:_id', function() {
this.render('ShowIdea', {
data: function () {return Ideas.findOne({_id: this.params._id})}
});
});
See this example from the docs. After making those changes, the code worked correctly for me.

Is there are more elegant way to walk template nesting?

I'm trying to access a parents data context
To get to it, I have a line that looks like :-
template.view.parentView.parentView.parentView.parentView.dataVar.curValue
Which in terms of UI, I have
template[dataIwant] renders another template with a modal dialog which uses autoform
I then use an autoform hook to get a before save event, which I want to use to add an extra value to the document being saved.
I then walk the template that's passed in the hook back to the top template. Seems like I should be able to do this in a more elegant way?
Came up with this code today because I needed it also :
_.extend(Blaze.View.prototype,{
closest: function(searchedViewName){
currentView = this;
while (currentView && currentView.name != searchedViewName){
currentView = currentView.parentView;
}
return currentView;
}
});
<template name="parent">
{{> child}}
</template>
Template.parent.created = function(){
this.reactiveVar = new ReactiveVar(false);
};
<template name="child">
{{parentName}}
{{parentVar}}
</template>
Template.child.helpers({
parentName:function(){
return Template.instance().view.closest("parent").name;
},
parentVar:function(){
return Template.instance().view.closest("parent")._templateInstance.reactiveVar.get();
}
});
So far so good, but I've already spotted use cases where this won't work (using Template.contentBlock in your template definition is breaking the whole thing for some unknown reason).

Controlling JS load order in Meteor with nested templates breaks with template.rendered?

I've got this template named indexmade up of a bunch of partial templates.
<template name="index">
{{> jumbotron }}
{{> crew }}
{{> projects3 }}
{{> projects2 }}
{{> faq }}
{{> contact }}
</template>
Say that I've got JS code page-transitions.js that requires the DOM of jumbotron to be fully loaded in order to run.
It's not enough to simple do:
Template.index.rendered = function(){
// load page-transitions.js
};
I HAVE to do
Template.jumbotron.rendered = function(){
// load page-transitions.js here instead
};
This can get messy really quick because you need to be VERY specific about which partial templates need which JS code. And different templates could require the same JS code so you can run into a situation where you're loading the same JS code multiple times.
Is there a way to wait until the index template has completely rendered EVERYTHING, including all nested child templates, and then run the JS code?
Meteor.startup() doesn't work in this case either.
You can try a couple of things:
First, just use the classic jQuery.ready way. because, why not?
Meteor.startup(function() {
$(document).ready(function() {
// stuff.
});
});
Or you could try Tracker.afterFlush:
Meteor.startup(function() {
// I know each Template.template.rendered has its own afterFlush, but those
// computations are defined way before Meteor.startup so then, theoretically,
// the below code should be executed last even if it triggers recomputations here.
Tracker.afterFlush(function() {
// stuff.
});
});

Meteor template gets rendered twice

My template is getting rendered twice on first load. I notice this because in
Template.home.rendered = function() {
console.log('rendered'); // => this is printed out twice
console.log(Data.find({}).count()); // => this is initially 0, then 1 the second time
}
Furthermore, on the first load, no Data is available. Yet on the second load, the Data is there.
Does anyone know what this problem might be, and why the data only appears the second time?
You need to find a way to render the template when your data is available.
Using this template structure, the if block content, which happens to be the template displaying your data, will be rendered only when the myDataIsReady helper returns true. (thus triggering the rendered callback only once, with data immediately available).
<template name="displayData">
<p>This is my data : {{this}}</p>
</template>
<template name="home">
{{#if myDataIsReady}}
{{#each data}}
{{> displayData}}
{{/each}}
{{/if}}
</template>
You have to define a subscription handle (an object returned by Meteor.subscribe) in order to use it's reactive ready method : we'll reference it in the myDataIsReady helper to track data availability, and the helper will automatically rerun when the state of ready changes.
Meteor.startup(function(){
// this subscription should return your data subset
myDataHandle=Meteor.subscribe("myData");
});
Template.home.myDataIsReady=function(){
return myDataHandle.ready();
}
Template.home.data=function(){
return Data.find({});
}
But that's quite annoying for such a simple task.
That's why I suggest using the Iron Router which makes things way simpler !
Add it to your project using "mrt add iron-router", then in a client/router.js and client/router.html, use this boilerplate code :
Router.configure({
loadingTemplate:"loading"
});
Router.map(function(){
this.route("home",{
path:"/",
// we indicate which subscription has to be marked ready in order to load the template
waitOn:function(){
return Meteor.subscribe("myData");
}
// the result of this function will become our target template data context
data:function(){
return Data.find({});
}
});
});
<template name="home">
{{#each this}}
{{> displayData}}
{{/each}}
</template>
<template name="loading">
<p>Data isn't ready yet...</p>
</template>
As you can see, the Iron Router allows us to specify simply what we painfully achieved manually in the first code example (waiting on a particular subscription to render a template), and of course we get free routing, loading mechanisme, layout management, etc...
Search the web for a complete iron-router tutorial (my code is untested, but I hope it is ok and should get you started), it's so awesome that it's gonna be merged to Meteor ultimately.
I had a body.html in /client and a appBody.html in /client/templates, with, in iron router:
Router.configure({
layoutTemplate: 'appBody',
});
Both body templates were rendered (and happened to be the same). Obviously, the body.html in /client needed to be removed.

Meteor: Passing more than one value to a template

I want to create a template/js combo similar to the ones below. What I would like is to have two variables available to the 'collection' template
<template name="collection">
Title: {{title}}
<UL>
{{#each items}}
{{> item}}
{{/each}}
</UL>
</template>
<template name="collection_items">
<LI>{{item_title}}</LI>
</template>
Where the javascript function would be something like:
Template.collection.data = function() {
var record = Record.findOne({whatever:value});
return { title: record.title, items: record.items }
}
I've tried using Handlebars' {{#with data}} helper and return an object as above, but that just crashed the template. I've tried creating a 'top level' function like:
Template.collection = function () {... }
but that also crashed the template.
What I'm trying to avoid is having two separate functions (one Template.collection.title, and one Template collection.items) where each of them calls a findOne on the Record collection where really its the same template and one call should suffice.
Any ideas?
Template.collection = function () {... }
Template.collection is not a function, it's an instance and thus an object.
You can type Template.collection in the console to see something essential as well as Template.collection. and autocomplete that to see its methods and fields.
For a #with example, the Todos indeed doen't seem to contain one as you have outlined in your comments. So, an example use of it can be found here:
https://github.com/meteor/meteor/blob/master/packages/templating/templating_tests.js#L75
https://github.com/meteor/meteor/blob/master/packages/templating/templating_tests.html#L92
Here is another example that I tried that works on both the current master and devel branch:
<head>
<title>test</title>
</head>
<body>
{{> hello}}
</body>
<template name="hello">
{{#with author}}
<h2>By {{firstName}} {{lastName}}</h2>
{{/with}}
</template>
And the JS part of it:
if (Meteor.is_client) {
Template.hello.author = function () {
return {
firstName: "Charles",
lastName: "Jolley"
};
};
}
Any specific reason why you're hoping to avoid two functions?
From your code sample I see one issue: the first template is calling a second template with this line:
{{> item}}
But your second template is not called 'items'. I believe that your second template should be called this way:
<template name="item">
Seems that it would be simple enough to have helper functions for the first and the second. Although I haven't gotten it to work with my own code, I believe the second helper function would want to use the 'this' convention to refer to the collection you're referring to.
Cheers - holling
Tom's answer is correct. I want to just chime in and add that in my scenario the reason why #with was failing was because due to the 'reactive' nature of meteor my first call to load the model resulted in 'undefined' and I didn't check for it. A fraction later it was loaded ok.
The moral is to do something like
var record = Record.findOne({whatever:value})
if (record) {
return record;
} else {
// whatever
return "loading"
}

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