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).
Related
i want to refresh/reload a part of my template after a variable change so that if the variable is true it shows a content A or else it will show content B. I'm sure this is a quite simple question but i'm having troubles on finding the solution.
Something like this:
Template.x.created = function() {
this.variable = false;
}
Template.x.helpers({
'getValue': function(){
return this.variable;
}
});
Template:
<template name="x">
{{#if getValue}}
<content A>
{{else}}
<content B>
{{/if}}
</template>
You need to create a reactive data source to get the template helper to re-run when the variable changes, as a normal variable won't let the helper know when it changes value. The simplest solution is to use ReactiveVar:
Template.x.onCreated(function() {
this.variable = new ReactiveVar(false);
});
Template.x.helpers({
'getValue': function() {
// Note that 'this' inside a template helper may not refer to the template instance
return Template.instance().variable.get();
}
});
If you need to access the value somewhere outside this template, you can use Session as an alternative reactive data source.
#Waiski answer is a good one, but I want to share a simple Template helper I build because a lot of Templates need this:
Using registerHelper you can build a global helper like so:
Template.registerHelper('get', function (key) {
let obj = Template.instance()[key]
return (obj && obj.get) ? obj.get() : obj
})
Use it in every template:
Template.x.onCreated(function() {
this.foo = new ReactiveVar(true)
this.bar = new ReactiveVar('abc')
})
Html:
{{#let foo=(get 'foo')}}
{{#if get 'bar'}}
Bar is true. Foo: {{foo}}
{{/if}}
{{/let}}
Could anybody point me how to access an original TemplateInstance from the meteor helper. I'm aware of the Template.instance() but it appears to return the template instance where the helper was called, not the template instance for which the helper was defined.
Imagine we have two tiny templates:
<template name='demo'>
<h1>{{helper}}</h1>
{{# border}}
<h2>{{helper}}</h2>
{{/border}}
</template>
<template name='border'>
<div style="border:1px solid red">
{{> UI.contentBlock}}
</div>
</template>
With the following behavior:
Template.demo.created = function() {
this.result = "OK";
}
Template.demo.helpers({
helper: function() {
var tmpl = Template.instance();
return tmpl.result || "FAILED";
}
});
I've expected to obtain two "OK" for the demo template: the second one should be in the red border. But since Template.instance() returns original TemplateInstance only when helper is called at the top level of its owner template the result is "FAILED" (of course in the red border).
Question: Is there any public api to get the original TemplateInstance (without need to traverse view/parentView/_templateInstace)?
I think the best way to do this might be to either just set a Session variable, or use a Reactive Variable (using the reactive-var package - here is the documentation).
I've made a meteor pad to show how this more - here.
Basically:
Template.demo.created = function() {
result = new ReactiveVar('OK');
}
Template.demo.helpers({
helper: function() {
return result.get() || "FAILED";
}
});
I think your main problem is that you not setting a template instance variable correctly. Try the below code...
Set an instance variable:
Template.instance().result.set("OK");
Get an instance variable:
Template.instance().get("result");
So your updated code would be:
Template.demo.created = function() {
Template.instance().result.set("OK");
}
Template.demo.helpers({
helper: function() {
return Template.instance().get("result") || "FAILED";
}
});
It seems that it's known and already fixed (?) Meteor bug. More here: https://github.com/meteor/meteor/issues/3745
Comment from rclai on GitHub:
This was already addressed and fixed for the next release.
Run meteor like this, not sure if it still works:
meteor --release TEMPLATE-CURRENT-DATA#0.0.1
Another alternative is to use aldeed:template-extensions, which has super nice features, especially with dealing with template instances and I believe their way of fetching the template instance is a workaround this issue.
I have the following templates (.html) with their respected managers (.js files):
adminManageCategories
adminAddCategory
adminUpdateCategory
Consider the following:
<template name="adminManageCategories">
{{#each category}}
<div class="clickme">{{title}}</div>
{{/each}}
{{> adminUpdateCategory}}
</template>
Notice the {{> adminUpdateCategory}} is outside of the iteration. This is also a form, and I want to keep it on the same page.
And admin_manage_categories.js
Template.adminManageCategories.events({
"click .clickme": function(event) {
event.preventDefault();
console.log(this._id);
}
});
Notice the console.log() function, which works, as the template manager is smart enough to know the ID of the item that was clicked.
What I want to do is load this items values into the form when clicked. My example above is slim, but in my real data I have a title, sort order, among other things.
So my question is, what is the proper way to pass the _id from the adminManageCategories template to the adminUpdateCategory template, which is the form?
I can hack at this with JavaScript and make things happen, but I think I'm missing a "Meteor way" of doing things.
You need to use a ReactiveVar to store the currently clicked item.
First you need to run meteor add reactive-var, as it's not a package added by default in a standard meteor web app.
JS:
Template.adminManageCategories.created=function(){
// instantiate the reactive-var in the created callback
// we store it as a property of the template instance
this.currentItemId=new ReactiveVar(null);
};
Template.adminManageCategories.helpers({
// this helper reactively returns the currently clicked item
currentItem:function(){
// retrieve the reactive-var from the template instance...
var currentItemId=Template.instance().currentItemId.get();
// ...to fetch the correct collection document
return Items.findOne(currentItemId);
}
});
Template.adminManageCategories.events({
"click .clickme": function(event,template) {
event.preventDefault();
// assign the correct item id to the reactive-var attached to this template instance
template.currentItemId.set(this._id);
}
});
HTML:
<template name="adminManageCategories">
{{#each category}}
<div class="clickme">{{title}}</div>
{{/each}}
<p>Current item title is : {{currentItem.title}}</p>
{{! pass the currentItem as a parameter to your child template this will be
accessible as {{item}} in the HTML and "this.item" in JS helpers or
"this.data.item" in created/rendered/destroyed callbacks}}
{{> adminUpdateCategory item=currentItem}}
</template>
EDIT:
When I initialize the reactive-var in the created callback, I set it to null, this means that until one item is clicked, the helper will return null too and when you'll try to access this.item._id in the adminUpdateCategory this will fail.
The simplest way to solve this issue is maybe to not initialize the variable to null but to the first item in the collection.
Template.adminManageCategories.created=function(){
var firstItem=Items.findOne({},{
sort:{
sortedField:1
}
});
this.currentItemId=new ReactiveVar(firstItem && firstItem._id);
};
There may still be a case when you have 0 items in the collection, so you'll probably end up having to guard against the existence of the item in the JS.
Template.adminUpdateCategory.helpers({
itemProperty:function(){
return this.item && this.item.property;
}
});
Is it possible for a parent Meteor template to access a subtemplate directly? Ideally, I'd like to use templates a widgets with an API. I was hoping for something like this:
mypage.html
<template name="myPage">
<div class="widgetContainer"></div>
<button>submit</button>
</template>
mypage.js
Template.myPage.rendered = function(){
this.myWidgetInstance = UI.render(Template.myWidget)
UI.insert(this.myWidgetInstance, $('.widgetContainer')[0]);
}
Template.myPage.events({
'click button': function(e, template){
// I don't want this logic to live inside of mywidget.js.
// I also don't want this template to know about the <input> field directly.
var val = template.data.myWidgetInstance.getMyValue();
}
});
mywidget.html
<template name="myWidget">
<input></input>
</template>
mywidget.js
Template.myWidget.getValue = function(){
return this.$('input').val();
}
The above doesn't work because myWidgetInstance.getMyValue() doesn't exist. There doesn't appear to be a way for external code to access template helper functions on an instance.
Is anyone using Meteor templates in the way I'm trying to use them above? Or is this better suited for a separate jQuery widget? If so, it'd be a shame because I still want my widget template to benefit from the features Meteor provides.
It is possible to access subtemplate helper function.
Your example will work once you apply few fixes:
fix 1 : getValue() instead of getMyValue()
Template.myPage.events({
'click button': function(e, template){
// I don't want this logic to live inside of mywidget.js.
// I also don't want this template to know about the <input> field directly.
var val = template.myWidgetInstance.getValue();
console.log(val);
}
});
fix 2 : $('input').val(); instead this.$('input').val();
Template.myWidget.getValue = function(){
return $('input').val();
}
fix 3 : <input> should have no close tag.
<template name="myWidget">
<input type="text" value="sample value">
</template>
Ok so I've got my template in its own file named myApp.html. My template code is as follows
<template name="initialInsertion">
<div class="greeting">Hello there, {{first}} {{last}}!</div>
</template>
Now I want to insert this template into the DOM upon clicking a button. I've got my button rendered in the DOM and I have a click event tied to it as follows
Template.chooseWhatToDo.events = {
'click .zaButton':function(){
Meteor.ui.render(function () {
$("body").append(Template.initialInsertion({first: "Alyssa", last: "Hacker"}));
})
}
}
Now obviously the $("body").append part is wrong but returning Template.initialInsertion... doesn't insert that template into the DOM. I've tried putting a partia {{> initialInsertion}}but that just errors out because I dont have first and last set yet... any clues?
Thanks guys
In meteor 1.x
'click .zaButton':function(){
Blaze.renderWithData(Template.someTemplate, {my: "data"}, $("#parrent-node")[0])
}
In meteor 0.8.3
'click .zaButton':function(){
var t = UI.renderWithData(Template.someTemplate, {my: "data"})
UI.insert(t, $(".some-parrent-to-append"))
}
Is first and last going into a Meteor.Collection eventually?
If not, the simplest way I know is to put the data into the session:
Template.chooseWhatToDo.events = {
'click .zaButton' : function () {
Session.set('first', 'Alyssa');
Session.set('last', 'Hacker');
}
}
Then you would define:
Template.initialInsertion.first = function () {
return Session.get('first');
}
Template.initialInsertion.last = function () {
return Session.get('last');
}
Template.initialInsertion.has_name = function () {
return Template.initialInsertion.first() && Template.initialInsertion.last();
}
Finally, adjust your .html template like this:
<template name="initialInsertion">
{{#if has_name}}
<div class="greeting">Hello there, {{first}} {{last}}!</div>
{{/if}}
</template>
This is the exact opposite solution to your question, but it seems like the "Meteor way". (Basically, don't worry about manipulating the DOM yourself, just embrace the sessions, collections and template system.) BTW, I'm still new with Meteor, so if this is not the "Meteor way", someone please let me know :-)
I think you may want to use Meteor.render within your append statement. Also, note that if you are passing data into your Template, then you must wrap Template.initialInsertion in an anonymous function, since that's what Meteor.render expects. I'm doing something similar that seems to be working:
Template.chooseWhatToDo.events = {
'click .zaButton':function(){
$("body").append(Meteor.render(function() {
return Template.initialInsertion({first: "Alyssa", last: "Hacker"})
}));
}
}
Hope this helps!
Many answer here are going to have problems with the new Blaze engine. Here is a pattern that works in Meteor 0.8.0 with Blaze.
//HTML
<body>
{{>mainTemplate}}
</body>
//JS Client Initially
var current = Template.initialTemplate;
var currentDep = new Deps.Dependency;
Template.mainTemplate = function()
{
currentDep.depend();
return current;
};
function setTemplate( newTemplate )
{
current = newTemplate;
currentDep.changed();
};
//Later
setTemplate( Template.someOtherTemplate );
More info in this seccion of Meteor docs