Handlebars block helper inside quotes - ember.js

don't know if block helper is the right name but hope you get the point.
In Ember 1.8.0-beta.2 i can not do
<img src="{{url}}">
Chrome gives me:
Uncaught TypeError: Cannot read property 'parentNode' of null
Uncaught TypeError: Cannot set property 'profileNode' of undefined
And Firefox gives me:
TypeError: ref is null
var parent = ref.parentNode;
The error comes from vendor.js
hydrateMorphs: function () {
var childViews = this.childViews;
var el = this._element;
for (var i=0,l=childViews.length; i<l; i++) {
var childView = childViews[i];
var ref = el.querySelector('#morph-'+i);
var parent = ref.parentNode; // This line
childView._morph = this.dom.insertMorphBefore(parent, ref);
parent.removeChild(ref);
}
}
I know that i simply can do a handlebars helper to output the img tag with right src but i want to be able to use the {{url}} to set a divs background property aswell.
(the url property is just a simplified version. In my app i have a helper thats takes an array of images and maxWidth to to give me the best picture depending on the width. But {{url}} does not work either)

forgot that I just can use unbound:
<img src="{{unbound url}}">

You can't use that syntax in ember handlebars. The accepted one is bind-attr.
Usage examples: http://emberjs.com/guides/templates/binding-element-attributes/
More info: http://www.emberist.com/2012/04/06/bind-and-bindattr.html

Related

django-autocomplete-light add parameter to query url

I'm trying to pass some data along to the autocomplete_light.AutocompleteModelBase so I can exclude some models from the search. I'm trying to use the Dependencies info in the docs here
but I can seem to get it.
The id of the input is id_alternate_version-autocomplete, so I'm trying:
$("#id_alternate_version-autocomplete").yourlabsWidget().autocomplete.data = {'id': 'foo'};
But the url called looks like http://127.0.0.1:8000/autocomplete/FooAutocomplete/?q=bar
I want: http://127.0.0.1:8000/autocomplete/FooAutocomplete/?q=bar&id=foo
How can I do something like that?
DAL provides a way to do this with "forwarding" of another rendered form field's value.
See http://django-autocomplete-light.readthedocs.io/en/master/tutorial.html#filtering-results-based-on-the-value-of-other-fields-in-the-form
This is how I did it:
$(document).ready(function() {
$('form#recipe').on('change propertychange keyup input paste', function() {
var ingredient_item_type = $("form#recipe input[type='radio']:checked").val();
var widget = $("form#recipe input#id_ingredients_text").parents('.autocomplete-light-widget');
if(ingredient_item_type) {
widget.yourlabsWidget().autocomplete.data['hello'] = 'world';
}
});
});
Javascript acrobatics aside, the key observation is thus:
anything you put in the .data object of the autocomplete widget will
automatically be made part of the GET request. HTH.

How can I dynamically render HTML using Meteor Spacebars templates?

So let's say I'm storing <div>{{name}}</div> and <div>{{age}}</div> in my database.
Then I want to take the first HTML string and render it in a template - {{> template1}} which just renders the first string with the {{name}} handlebar in it. Then I want to give that newly generated template/html data, so that it can fill in the handlebar with the actual name from the database, so that we would get <div>John</div>. I've tried doing
<template name="firstTemplate">
{{#with dataGetter}}
{{> template1}}
{{/with}}
</template>
Where template1 is defined as
<template name="template1">
{{{templateInfo}}}
</template>
And templateInfo is the helper that returns the aforementioned html string with the handlebar in it from the database.
dataGetter is just this (just an example, I'm working with differently named collections)
Template.firstTemplate.dataGetter = function() {
return Users.findOne({_id: Session.get("userID")});
}
I can't get the {{name}} to populate. I've tried it a couple of different ways, but it seems like Meteor doesn't understand that the handlebars in the string need to be evaluated with the data. I'm on 0.7.0 so no Blaze, I can't upgrade at the moment due to the other packages I'm using, they just don't have 0.8+ version support as of yet. Any ideas on how I can get this to work are much appreciated.
In 1.0 none of the methods described above work. I got this to work with the function below defined in the client code. The key was to pass the options { isTemplate: true} to the compile function.
var compileTemplate = function(name, html_text) {
try {
var compiled = SpacebarsCompiler.compile(html_text, { isTemplate:true });
var renderer = eval(compiled);
console.log('redered:',renderer);
//Template[name] = new Template(name,renderer);
UI.Template.__define__(name, renderer);
} catch (err){
console.log('Error compiling template:' + html_text);
console.log(err.message);
}
};
The you can call with something like this on the client:
compileTemplate('faceplate', '<span>Hello!!!!!!{{_id}}</span>');
This will render with a UI dynamic in your html
{{> Template.dynamic template='faceplate'}}
You can actually compile strings to templates yourself using the spacebars compiler.. You just have to use meteor add spacebars-compiler to add it to your project.
In projects using 0.8.x
var compiled = Spacebars.compile("<div>{{name}}</div> and <div>{{age}}</div>");
var rendered = eval(compiled);
Template["dynamicTemplate"] = UI.Component.extend({
kind: "dynamicTemplate",
render: rendered
});
In projects using 0.9.x
var compiled = SpacebarsCompiler.compile("<div>{{name}}</div> and <div>{{age}}</div>");
var renderer = eval(compiled);
Template["dynamicTemplate"] = Template.__create__("Template.dynamicTemplate", rendered);
Following #user3354036's answer :
var compileTemplate = function(name, html_text) {
try {
var compiled = SpacebarsCompiler.compile(html_text, { isTemplate:true }),
renderer = eval(compiled);
console.log('redered:',renderer);
//Template[name] = new Template(name,renderer);
UI.Template.__define__(name, renderer);
} catch (err) {
console.log('Error compiling template:' + html_text);
console.log(err.message);
}
};
1) Add this in your HTML
{{> Template.dynamic template=template}}
2) Call the compileTemplate method.
compileTemplate('faceplate', '<span>Hello!!!!!!{{_id}}</span>');
Session.set('templateName','faceplate');
Save the template name in a Session variable. The importance of this is explained in the next point.
3) Write a helper function to return the template name. I have used Session variable to do so. This is important if you are adding the dynamic content on a click event or if the parent template has already been rendered. Otherwise you will never see the dynamic template getting rendered.
'template' : function() {
return Session.get('templateName');
}
4) Write this is the rendered method of the parent template. This is to reset the Session variable.
Session.set('templateName','');
This worked for me. Hope it helps someone.
If you need to dynamically compile complex templates, I would suggest Kelly's answer.
Otherwise, you have two options:
Create every template variation, then dynamically choose the right template:
eg, create your templates
<template name="displayName">{{name}}</template>
<template name="displayAge">{{age}}</template>
And then include them dynamically with
{{> Template.dynamic template=templateName}}
Where templateName is a helper that returns "age" or "name"
If your templates are simple, just perform the substitution yourself. You can use Spacebars.SafeString to return HTML.
function simpleTemplate(template, values){
return template.replace(/{{\w+}}/g, function(sub) {
var p = sub.substr(2,sub.length-4);
if(values[p] != null) { return _.escape(values[p]); }
else { return ""; }
})
}
Template.template1.helpers({
templateInfo: function(){
// In this context this/self refers to the "user" data
var templateText = getTemplateString();
return Spacebars.SafeString(
simpleTemplate(templateText, this)
);
}
Luckily, the solution to this entire problem and any other problems like it has been provided to the Meteor API in the form of the Blaze package, which is the core Meteor package that makes reactive templates possible. If you take a look at the linked documentation, the Blaze package provides a long list of functions that allow for a wide range of solutions for programmatically creating, rendering, and removing both reactive and non-reactive content.
In order to solve the above described problem, you would need to do the following things:
First, anticipate the different HTML chunks that would need to be dynamically rendered for the application. In this case, these chunks would be <div>{{name}}</div> and <div>{{age}}</div>, but they could really be anything that is valid HTML (although it is not yet part of the public API, in the future developers will have more options for defining this content in a more dynamic way, as mentioned here in the documentation). You would put these into small template definitions like so:
<template name="nameDiv">
<div>{{name}}</div>
</template>
and
<template name="ageDiv">
<div>{{age}}</div>
</template>
Second, the definition for the firstTemplate template would need to be altered to contain an HTML node that can be referenced programmatically, like so:
<template name="firstTemplate">
<div></div>
</template>
You would then need to have logic defined for your firstTemplate template that takes advantage of some of the functions provided by the Blaze package, namely Blaze.With, Blaze.render, and Blaze.remove (although you could alter the following logic and take advantage of the Blaze.renderWithData function instead; it is all based on your personal preference for how you want to define your logic - I only provide one possible solution below for the sake of explanation).
Template.firstTemplate.onRendered(function() {
var dataContext = Template.currentData();
var unrenderedView = Blaze.With(dataContext, function() {
// Define some logic to determine if name/age template should be rendered
// Return either Template.nameDiv or Template.ageDiv
});
var currentTemplate = Template.instance();
var renderedView = Blaze.render(unrenderedView, currentTemplate.firstNode);
currentTemplate.renderedView = renderedView;
});
Template.firstTemplate.onDestroyed(function() {
var renderedView = Template.instance().renderedView;
Blaze.remove(renderedView);
});
So what we are doing here in the onRendered function for your firstTemplate template is dynamically determining which of the pieces of data that we want to render onto the page (either name or age in your case) and using the Blaze.With() function to create an unrendered view of that template using the data context of the firstTemplate template. Then, we select the firstTemplate template element node that we want the dynamically generated content to be contained in and pass both objects into the Meteor.render() function, which renders the unrendered view onto the page with the specified element node as the parent node of the rendered content.
If you read the details for the Blaze.render() function, you will see that this rendered content will remain reactive until the rendered view is removed using the Blaze.remove() function, or the specified parent node is removed from the DOM. In my example above, I am taking the reference to the rendered view that I received from the call to Blaze.render() and saving it directly on the template object. I do this so that when the template itself is destroyed, I can manually remove the rendered view in the onDestroyed() callback function and be assured that it is truly destroyed.
A very simple way is to include in the onRendered event a call to the global Blaze object.
Blaze.renderWithData(Template[template_name], data ,document.getElementById(template_id))

Ignore or replace Handlebars blocks that don't compile

In a handlebars template in Ember.js, I have blocks like the following:
{{content.some_attribute}}
{{content.some_other_attr}}
{{content.more_attr}}
Some of these attributes don't exist and I'm implementing them slowly.
Is there a way to get these templates to compile and either ignore the blocks that don't evaluate or better yet, replace them with a html element so they're easier to spot in the browser?
(the template is pretty large and it's being converted from ERB slowly,
Is there a way to get these templates to compile and either ignore the blocks that don't evaluate
Properties that don't exist are undefined, and don't get rendered at all. In other words {{thisDoesNotExist}} will simply be invisible -- it will compile just fine.
or better yet, replace them with a html element so they're easier to spot in the browser
As Cory said, you could use a helper for this that checks for undefined, using Ember.Handlebars.registerBoundHelper.
This seems like a perfect case for a handlebars helper. The helper could validate the value and return the value or the html that you desire.
The following code should be used very carefully, since it has not been tested within an application.
A possible solution to replace the possible undefined value in a template is to overwrite Ember.getPath, which is used to lookup the value of a path in a template, see http://jsfiddle.net/pangratz666/hKK8p/:
var getPath = Ember.getPath;
Ember.getPath = function(obj, path) {
var value = getPath(obj, path);
return (Ember.none(value) ? 'OMG %# is not defined!!'.fmt(path) : value);
};
If this code would be used temporarily in an application, I would also restrict the check for undefined values to a specific obj. So something along those lines:
App.objectWhichHasUndefinedProps = Ember.Object.create({
...
});
Ember.View.create({
templateName: 'templateWithAttributes',
objBinding: 'App.objectWhichHasUndefinedProps'
}).append();
var getPath = Ember.getPath;
Ember.getPath = function(obj, path) {
var value = getPath(obj, path);
if (obj === App.objectWhichHasUndefinedProps) {
return (Ember.none(value) ? 'OMG %# is not defined!!'.fmt(path) : value);
}
return value;
};

Writing a helper that produces bound results?

I have a date/time formatting helper but what it produces does not update when the underlying property changes. This is not a surprise, but does anyone know how to produce bindings in helpers?
I invoke the helper like this...
{{timestamp created_at}}
...and here is the helper itself:
Handlebars.registerHelper('timestamp', function(context, options) {
var formatter = options.hash['format'] ? options.hash['format'] : 'hh:mm a MM-DD-YYYY';
var original_date = Ember.getPath(this, context); // same as this.get(context) ?
var parsed_date = moment(original_date);
var formatted_date = parsed_date.format(formatter);
return new Handlebars.SafeString("<time datetime=" + original_date +">" + formatted_date + "</time>");
});
It is now possible to create bound Handlebars helpers using a public Ember API.
Handlebars.registerBoundHelper('timestamp', function(date, options) {
var formatter = options.hash['format'] ? options.hash['format'] : 'hh:mm a MM-DD-YYYY';
var parsed_date = moment(date);
var formatted_date = parsed_date.format(formatter);
return new Handlebars.SafeString("<time datetime=" + date +">" + formatted_date + "</time>");
});
The parameter passed to the helper will have already been resolved, and the helper will be called again whenever the path changes.
It is unfortunately more complex than I'd like to create a custom helper with bound content. Here's an example that Peter Wagenet wrote: https://gist.github.com/1563710
I'll be lobbying for this to become easier.
Not sure if this applies to this particular question, but I also created helpers in views and wanted the values to update when data in the Ember.js view changed. The way I solved this problem was to write an observer on the values I wanted changed and used jQuery to update the specific value.
For example (in Coffeescript):
...
attrObserver: Ember.observer(() ->
$("#attrId").text(this.get("attr"))
...

Django - jquery : populate combobox based on selection of another combobox

I am quite new to Django and jquery stuff. I am trying to populate a comboBox (ChoiceField in Django) based ont the choice selected in another comboBox (without reloading the page).
I can't find any simple example of such a basic application of ajax.
For now I'm call the following ajax function when I select an item from the first dropdown list.
function get_asset_from_type(){
var type_asset = $("#id_type").val();
var data = {type_asset:type_asset};
var args = {type:"POST", url:"/asset/etatType/", data:data};
$.ajax(args);
alert(type_asset);
return false;
};
It alerts the right type but gives a 403 error on the given url. Weird thing is this url works the first time I load the page. I don't understand what's going on..
EDIT:
403 error seems to be gone, remains the initial question :)
I think you're running up against a CSRF problem. As Django by default blocks POST requests that do not have a CSRF Token with a 403. There are a couple ways to deal with this in JS. One is to pull the value out of the cookie, the code to do that can be found here: https://docs.djangoproject.com/en/dev/ref/contrib/csrf/#ajax
or you can do it by passing the CSRF_TOKEN in with the javascript script tag:
<script src='myjavascript.js?CSRF_TOKEN={{ csrf_token }}'></script>
Note that it's using a double braket, instead of {%%}. This gets the value of the token, instead of the form input.
function getOptionsFromScriptSrc() {
// Get last script tag in parsed DOM.
// Due to the way html pages are parsed,
// the last one is always the one being loaded.
var options = {}
var js_src = $('script').last().attr('src');
if(js_src.match(/\?/)) {
var options_list = js_src.split('?')[1].split('&');
for(var i = 0; i < options_list.length; i++) {
var tmp = options_list[i].split('=');
options[$.trim(tmp[0])] = $.trim(tmp[1]);
}
}
return options;
}
function get_asset_from_type(){
var options = getOptionsFromScriptSrc();
var type_asset = $("#id_type").val();
var data = {type_asset: type_asset, csrfmiddlewaretoken: options['CSRF_TOKEN']};
var args = {type:"POST", url:"/asset/etatType/", data:data};
$.ajax(args);
alert(type_asset);
return false;
};
I haven't, of course, tested this code, but I have used this method before and it works pretty well.
To the main problem of populating a select box, you need to specify a callback for your ajax post, and then deal with the data returned from your server:
function get_asset_from_type(){
var options = getOptionsFromScriptSrc();
var type_asset = $("#id_type").val();
var post_data = {type_asset: type_asset, csrfmiddlewaretoken: options['CSRF_TOKEN']};
$.post('/asset/etatType/', post_data, function(data){
// Assuming server is going to respond with the html of the options, eg: <option value="1">One</option><option value="2">Two</option>...
$('#id_ofmyselectbox').append(data);
});
};