So, i have a little handlebars helper, for example
Handlebars.registerHelper('getTest', () => { test: 'test' });
If i call this helper in template, can i use something like this
{{(getTest).test}}
Trying to use different brackets, like with arrays [ ], didn't helped.
I think, it can be done.
Thanks!
In this case we should use {{#with}} helper. So, in my case, final code is
{{#with (getTest)}}
{{test}}
{{/with}}
You might find a helper like this useful if a section of your JSON object contains deeply nested properties, and you want to avoid repeating the parent name.
block helpers docs
As per the Handlebars syntax, you should call your helper as,
{{getTest test}}
Also, consider updating your helper function as below if you just require the helper to return the test value back to the template.
Handlebars.registerHelper('getTest', (val) => {return val});
Tested using http://tryhandlebarsjs.com.
Hope this helps.
Related
I am using a helper inside another helper. I am trying to pass a value ‘post_id’, that i am getting dynamically from ‘show_post’ helper.I want to pass it and then use it inside the query that is returning a set of result back to helper. for some reason , app is crashing. Can someone guide me through this.
{{#each show_post}}
{{posttext}}
{{postedBy}}
{{#each show_comment({{post_id}}) }}
//<--- i am passing the value to helper like this.
<span> <p>{{postedBy}}: <h5>{{commenttext}}</h5>{{createdAt}}</p></span>
{{/each}}
{{/each}}
Template.display_block.helpers({
show_post(){
return PostComment.find({parent: 0},{sort: {createdAt: -1}});
}
});
Template.display_block.helpers({
show_comment(e){
var t1 = e;
var now = PostComment.find({post_id:{$regex:new RegExp(’^’ + t1)}});
return now;
}
});
The first helper generates a array(Mongo Db result).I want to use this array’s elements(that are dynamic) in next helper. So i want to use a variable that can hold the value of array element of first helper and then pass it to next helper. In second helper, i want to pass this variable and use this variable to sort a result in Mongo query. I am new to this so i am unable to understand how this instance
Firstly you don't need to wrap helper arguments in double curly braces or parens.
{{#each show_comment post_id}}
Will do what you need.
You're also making life a bit more complicated for yourself than necessary. You can use the current data context through this in your code. Also unclear why you're using a regex unless you're concatenating something to the post _id.
This allows you to simplify down to:
html:
{{#each show_post}}
{{posttext}}
{{postedBy}}
{{#each show_comment}}
<span><p>{{postedBy}}: <h5>{{commenttext}}</h5>{{createdAt}}</p></span>
{{/each}}
{{/each}}
js:
Template.display_block.helpers({
show_comment(){
return PostComment.find({post_id: this._id);
}
});
In my js file, I pass a JSON object with two keys - {'tests': tests, 'isComplete': isComplete}
In my handlebars file, I want to display the tests object based on each test status. At the same time, there's another condition for which I added a helper named 'isRequired' that I want to check the test against only if isComplete is not true.
{{#if isComplete}}
{{#each tests}}
{{#isRequired this}}
// display data
{{/isRequired}}
{{/each}}
{{else}}
{{#each tests}}
// display data
{{/each}}{{/if}}
This code has the duplicate code to display data. I'm still learning handlebars and not sure how to eliminate this redundant code block. Can you help me how I can refactor this? Thank you!
I would probably solve this by adding an isComplete parameter to your isRequired helper. You have not provided the code for your helper, but I imagine it would end up looking something like this:
Handlebars.registerHelper('isRequired', function (context, isComplete, options) {
if (!isComplete) { return options.fn(context); }
/* rest of isRequired implementation here */
});
Your template would then be updated as follows:
{{#each tests}}
{{#isRequired this ../isComplete}}
// display data
{{/isRequired}}
{{/each}}
Note that this implementation applies the isRequired logic only if isComplete is true. This is the same rules as exist in your template code sample. However, these rules appear to contradict the text of your question, which specifies that isRequired should be applied "only if isComplete is not true". If these are the requirements we must meet, we need only remove the not operator from our new guard clause:
if (isComplete) { return options.fn(context); }
Let's say I have the following Blaze template helper that fetches some objects from a collection:
PackageInCart: function() {
PackageIds = Carts.findOne({SessionId: SessionID}).Packages;
var PackageObjects = Packages.find({ _id: { $in : PackageIds } } ).fetch();
return PackageObjects;
},
The PackageObjects variable contains objects that have a 'priceperday' property with a certain price value. In the Blaze template, I can easily print this value using:
{{#each PackageInCart}}
<div class="price">{{priceperday}}</div>
{{/each}}
However, what if I want to modify the 'priceperday' value from the Helper function before it gets printed in the template? What would be the correct way to do this?
One solution that came to mind was to make a for loop that iterates over the objects and does something like Object.defineProperty() to change the priceperday property into the new value.
I want to know if there's an easier or quicker way using Blaze methods to modify the object property that gets printed with the curly braces.
If you want to do this using blaze you could do this using another helper.
weeklyPrice: function(priceperday){
return priceperday * 7;
}
Which would be called like this
{{#each PackageInCart}}
<div class="price">{{weeklyPrice priceperday}}</div>
{{/each}}
More info about spacebars helper arguments in the docs
everybody :) For example I have something like this:
{{> someCoolHelper
someParam1='someVal1'
someParam2='someVal2'
someParam3='SomeVal3'
someParam4=someAnotherHelper 'value param to this helper'
}}
So I have a function, that computes some value depending on parameter that can be passed in it. So how can I do this?
as you may read in a forum thread at meteor forum this is not possible by now in spacebars.
We began with a new package for chaining methods and arguments but its not released yet. What you could do is to use the WITH element like
Instead something like:
{{> someCoolHelper
someParam1='someVal1'
someParam2='someVal2'
someParam3='SomeVal3'
someParam4=someAnotherHelper 'value param to this helper'
}}
can be managed by:
{{#with someAnotherHelper 'value param to this helper' }}
{{> someCoolHelper
someParam1='someVal1'
someParam2='someVal2'
someParam3='SomeVal3'
someParam4=this
}}
{{/with}}
I don't like it, but sometimes necessary
Tom
P.S.: Or drop Spacebars and use React - you won't have such limitations there.
The placeholder solution until template sub expressions are available in Spacebars is to create an helper returning the adequate value in JS :
HTML
{{> myTemplate param1="A" param2=param2}}
JS
function someOtherHelper(param){
console.log(param);
}
Template.registerHelper("someOtherHelper", someOtherHelper);
Template.myTemplate.helpers({
param2: function(){
return someOtherHelper("B");
}
});
You can pass the output of a helper to another helper using parentheses. Pretty sure this is what you're after:
http://blazejs.org/guide/spacebars.html#Calling-helpers-with-arguments
You can also pass the output of a helper to a template inclusion or other helper. To do so, use parentheses to show precedence:
{{> Todos_item (todoArgs todo)}}
Here the todo is passed as argument to the todoArgs helper, then the output is passed into the Todos_item template.
Something I did in a recent project uses this functionality to allow conditional rendering of CSS classes to a component (stripped down for brevity):
# global helper to provide ternary operator
Template.registerHelper('ternary', (condition, resultTrue, resultFalse) => {
return condition ? resultTrue : resultFalse
})
# in my-template.js:
Template.My_template.helpers({
isComplete(score) {
return score === 1
}
})
# in my-template.html:
{{> some_component class=(ternary (isComplete this.score) "green" "red")}}
I got error message when trying to run existing meteor project.
$meteor
=> Started proxy.
=> Started MongoDB.
=> Errors prevented startup:
While building the application:
client/coinmx.html:169: TRIPLE template tag is not allowed in an HTML attribute
...title="Totals: {{{get...
^
In Meteor 0.8, it's possible to return a Javascript object which is directly rendered into HTML attributes versus earlier versions, where you had to render it yourself.
Old version:
<input name={{name}} title={{title}}>
helpers:
Template.foo.name = "fooName";
Template.foo.title = "fooTitle";
New version:
<input {{attributes}}>
helpers:
Template.foo.attributes = {
name: "fooName",
title: "fooTitle"
};
All of these can be functions, and reactive, etc. Because the object is rendered directly into attributes, there is no need for you to SafeString some manually rendered content as before. This is the recommended way to go if need to render HTML attributes.
See also the following for how conditional attributes work under this scheme:
https://github.com/meteor/meteor/wiki/Using-Blaze#conditional-attributes-with-no-value-eg-checked-selected
The error is pretty much explanatory: you cannot use {{{something}}} inside a HTML attribute, you need to use {{something}} instead. Depending on what the something is (it's not known from your question as you didn't provide the code), that's either all you need to do, or you can achieve similar functionality by returning new Handlebars.SafeString("result") from your helper instead of just "result". However, if you do, you need to be super sure that the thing you'll return won't break the HTML structure.
Hugo's answer above gave me the missing piece I needed for the same issue-- triple stashes in 0.8 no longer supported. Here is an example that hopefully helps.
Where you might have had {{{resolve}}} in your template, you would now do:
<template name='thing'>
<ol>
{{#each all}}
{{resolve}}
{{/each}}
</ol>
<template>
The helper code then makes use of Spacebars.SafeString which looks to be preferred with Blaze:
Template.thing.helpers({
all: function () {
return Things.find();
},
resolve: function () {
var result = "<li>";
for (var i = 0; i < this.arrayOfClassNames.length; ++i)
result += <'div class='" + this.arrayOfClassNames[i] + "'></div>";
result += "</li>";
return new Spacebars.SafeString(result);
}
});
The key here is to return the 'new Spacebars.SafeString(result)' to wrap your HTML (which must be well formed).