I'm currently rendering bootstrap modals on my webpage using MeteorJS's "renderWithData" method to load each template when it's needed.
I'm running into an issue where my helper methods which access the data in the modal using "Blaze.getData()" will occasionally return undefined and I'm unsure how to fix that.
The only way I've been able to replicate the issue is by constantly creating/destroying the modals and there doesn't seem to be anything that specifically causes the issue.
Here are the steps I've been taking:
1) I instantiate the modal with the proper data
Template.Courses.events({
'click .share-course': function (e,t) {
var courseID = $(e.target).data('courseid');
Template.instance().activeCourse.set(
createModalWithData(
{
currentInstance: Template.instance().activeCourse.get(),
template: Template.Enrollment_Generator,
dataToRender: {courseID: courseID}
}
));
$('#generateEnrollmentURL').modal('show');
}
});
Also, here is the code for "createModalWithData":
// Create a modal with a specific data context
// If modal template already exists, destroy
// and re-create with the new data context.
// If a location to render isn't specified, renders
// content in the body .
// Parameters: [Object] data { currentInstance : Template || null,
// template : Template,
// dataToRender : Object,
// (optional) location : Element
// Return: Blaze Template Instance
createModalWithData = function createModalWithData(data) {
// Ensure data exists
if (_.isUndefined(data) || _.isNull(data)) {
throw "data cannot be null or undefined";
}
// If modal already exists, destroy it
if (!_.isNull(data.currentInstance)) {
Blaze.remove(data.currentInstance);
}
// If location is undefined, set to page body
if (_.isUndefined(data.location)) {
data.location = document.body;
}
// Render modal with dataToRender
return Blaze.renderWithData(data.template,
data.dataToRender,
data.location
);
};
2) I attempt to retrieve the data using "Blaze.getData()" within my modal template
Template.Enrollment_Generator.onCreated(function() {
var courseID = Blaze.getData().courseID; // Occasionally undefined
Meteor.subscribe('enrollment-codes',courseID);
});
So far I've attempted to replace the "onCreated" method with "onRendered" but still had the same issue.
It turns out the issue was within the click event. I had a nested span element within my share-course button:
<small class="share-course" data-courseid="{{_id}}">
Share
<span class="glyphicon glyphicon-share"></span>
</small>
This was messing up the way I was targeting my embedded courseID
Instead of Blaze.getData(), I should have also been using Template.currentData() to retrieve the data within my template
As stated here: https://forums.meteor.com/t/blaze-getdata-question/5688
Related
I have a parent/child component setup where the parent is loading data from the server and passing it down to children via props. In the child I would like to instantiate a jQuery calendar with some of the data it receives from the parent.
In order to wait for the data before setting up the calendar, I broadcast an event in the parent that I have an event listener setup for in the child.
The listener is being fired in the child but if I this.$log('theProp'), it's undefined. However, if I inspect the components with the VueJs devtools, the parent/child relationship is there and the child has received the prop in the meantime.
The prop is defined on the child as a dynamic prop :the-prop="theProp". Since the child does receive the prop in the end, I'm assuming my setup is correct but there seems to be some sort of delay. The parent sets the props in the return function of the ajax call and again: it's working, just with a slight delay it seems.
I also tried registering a watch listener on the prop in the child so I could setup the calendar then and be sure that the prop is there. However, the watch listener fires, but this.$log('theProp') is still undefined.
If I pass the data along with the the broadcast call, like this.$broadcast('dataLoaded', theData) the child receives it just fine. But it seems wrong to do it that way as I'm basically building my own prop handler.
I'm not posting any code because the components are rather large and the VueJs devtools are telling me the parent/child situation is working.
Am I missing some information? Is there a slight delay between setting a value in the parent and the child receiving it? What would be the proper way to wait for parent data in the child?
Normally, when you're just rendering the data out into the template, the timing doesn't matter so much since the data is bound to the template. But in this case, I really need the data to be there to setup the calendar or it will be wrong.
Thanks.
edit 1: here's a jsfiddle: https://jsfiddle.net/dr3djo0u/1/
It seems to confirm that the data is not available immediately after the broadcast. However, the watcher does work, though I could almost swear that sometimes this.$log('someData') returned undefined when I setup that testcase.
But I guess my problem might be somewhere else, I'll have a look tonight, don't have the project with me right now.
edit 2: did some more tests. My problem was that a) event listeners do not seem to receive the data instantly and b) I was also trying to init the calendar in the route.data callback if someData was already around (e.g. when coming from parent), but that route callback is called before the component is ready, so it wasn't working there either.
My solution is now this:
// works when the child route is loaded directly and parent finishes loading someData
watch: {
someData() {
this.initCalendar();
}
},
// works when navigating from parent (data already loaded)
ready() {
if (this.someData && this.someData.length) {
this.initCalendar()
}
}
As far as I know, you should not need events to pass data from parent to child.
All you need is, in the child component: props: ['theProp']
And when using the child component in the parent: <child :theProp="someData"></child>
Now, wherever in the parent you change someData, the child component will react accordingly.
You don't need events, you don't need "watch", you don't need "ready".
For example: after an AJAX call, in the parent's "ready", you load some data:
// at the parent component
data: function () {
return {
someData: {}
}
},
ready: function () {
var vm = this;
$.get(url, function(response) {
vm.someData = response;
});
}
Now, you do not need anything else to pass the data to the child. It is already in the child as theProp!
What you really need to do is to have, in the child, something which reacts to data changes on its own theProp property.
Either in the interface:
<div v-if="theProp.id > 0">
Loaded!
</div>
Or in JavaScript code:
// at the child component
computed: {
// using a computed property based on theProp's value
awesomeDate: function() {
if (!this.theProp || (this.theProp.length === 0)) {
return false;
}
if (!this.initialized) {
this.initCalendar();
}
return this.theProp.someThing;
}
}
Update 1
You can also, in the parent, render the child conditionally:
<child v-if="dataLoaded" :theProp="someData"></child>
Only set dataLoaded to true when the data is available.
Update 2
Or maybe your issue is related to a change detection caveat
Maybe you're creating a new property in an object...
vm.someObject.someProperty = someValue
...when you should do...
vm.$set('someObject.someProperty', someValue)
...among other "caveats".
Update 3
In VueJS 2 you are not restricted to templates. You can use a render function and code the most complex rendering logic you want.
Update 4 (regarding OP's edit 2)
Maybe you can drop ready and use immediate option, so your initialization is in a single place:
watch: {
someData: {
handler: function (someData) {
// check someData and eventually call
this.initCalendar();
},
immediate: true
}
}
It's because tricky behavior in Vue Parent and Child lifecycle hooks.
Usually parent component fire created() hook and then mount() hook, but when there are child components it's not exactly that way: Parent fires created() and then his childs fire created(), then mount() and only after child's mount() hooks are loaded, parent loads his mount() as explained here. And that's why the prop in child component isn't loaded.
Use mounted() hook instead created()
like that https://jsfiddle.net/stanimirsp5/xnwcvL59/1/
Vue 3
Ok so I've spent like 1.5h trying to find out how to pass prop from parent to child:
Child
<!-- Template -->
<template>
<input type="hidden" name="_csrf_token" :value="csrfToken">
<span>
{{ csrfToken }}
</span>
</template>
<!-- Script -->
<script>
export default {
props: [
"csrfToken"
]
}
</script>
Parent
<!-- Template -->
<template>
<form #submit.prevent="submitTestMailForm" v-bind:action="formActionUrl" ref="form" method="POST">
...
<CsrfTokenInputComponent :csrf-token="csrfToken"/>
...
</form>
</template>
<!-- Script -->
<script>
...
export default {
data(){
return {
...
csrfToken : "",
}
},
methods: {
/**
* #description will handle submission of the form
*/
submitTestMailForm(){
let csrfRequestPromise = this.getCsrfToken();
let ajaxFormData = {
receiver : this.emailInput,
messageTitle : this.titleInput,
messageBody : this.bodyTextArea,
_csrf_token : this.csrfToken,
};
csrfRequestPromise.then( (response) => {
let csrfTokenResponseDto = CsrfTokenResponseDto.fromAxiosResponse(response);
this.csrfToken = csrfTokenResponseDto.csrToken;
this.axios({
method : "POST",
url : SymfonyRoutes.SEND_TEST_MAIL,
data : ajaxFormData,
}).then( (response) => {
// handle with some popover
})
});
},
/**
* #description will return the csrf token which is required upon submitting the form (Internal Symfony Validation Logic)
*/
getCsrfToken(){
...
return promise;
}
},
components: {
CsrfTokenInputComponent
}
}
</script>
Long story short
This is how You need to pass down the prop to child
<CsrfTokenInputComponent :csrf-token="csrfToken"/>
NOT like this
<CsrfTokenInputComponent csrf-token="csrfToken"/>
Even if my IDE keep me telling me yeap i can navigate with that prop to child - vue could not bind it.
solution (testing ok)
In child component just using the props data, no need to re-assignment props's values to data, it will be cause update bug!
vue child component props update bug & solution
https://forum.vuejs.org/t/child-component-is-not-updated-when-parent-component-model-changes/18283?u=xgqfrms
The problem is not how to pass data with props, but rather how to do two things at almost the same time.
I have an user account component that can edit users (with an user id) and add users (without id).
A child component shows checkboxes for user<->company assignments, and needs the user id to prepare API calls when the user account is saved.
It is important that the child component shows before saving the user account, so that things can be selected before the user is saved and gets an id.
So it has no user id at first: the id is passed to the child component as 'null'.
It updates when the user is stored and gets an id.
But at this point, it takes a very short time for the child to get the new id into its model.
If you call a function in the child component that relies on data that was just changing, it might happen that the function executes before the data is updated.
For cases like this, nextTick() is your friend.
import { nextTick } from 'vue';
...
saveAccount() {
axios.post(URL, this.userModel).then((result)) {
// our model gets an id when persisted
this.userModel.id=result.data.id;
nextTick( () => {
this.$refs.childComponent.doSomething();
});
}
}
I did one sample Searchapp using meteor add sebdah:autocompletion package.When ever given inputs it shows drop down list.In this list how to get selected value as shown below code:
Js Code :
Friends = new Meteor.Collection('friends');
if (Meteor.isClient) {
/**
* Template - search
*/
Template.search.rendered = function () {
AutoCompletion.enableLogging = true;
var res = AutoCompletion.init("input#searchBox");
console.log("res :"+res);
}
Template.search.events = {
'keyup input#searchBox': function (e,t) {
AutoCompletion.autocomplete({
element: 'input#searchBox', // DOM identifier for the element
collection: Friends, // MeteorJS collection object
field: 'name', // Document field name to search for
limit: 0, // Max number of elements to show
sort: {name: 1}
});
}
}
}
I didn't get any idea about this.So please suggest me how to get selected drop down list values?
AutoCompletion package doesn't give any good API to read value on select. Instead you need to manually read the value of input#searchBox.
Please take a look at source code.
I would recommend to implement searching in your meteor app using Arunoda's approach : https://meteorhacks.com/implementing-an-instant-search-solution-with-meteor.html
Is there a clean way to get the parent template of the current template? Nothing is officially documented in Meteor's API.
I'm talking about the Blaze.TemplateInstance, not the context (i.e. not Template.parentData).
In the end, I've extended the template instances similarly with Meteor's parentData, like this:
/**
* Get the parent template instance
* #param {Number} [levels] How many levels to go up. Default is 1
* #returns {Blaze.TemplateInstance}
*/
Blaze.TemplateInstance.prototype.parentTemplate = function (levels) {
var view = this.view;
if (typeof levels === "undefined") {
levels = 1;
}
while (view) {
if (view.name.substring(0, 9) === "Template." && !(levels--)) {
return view.templateInstance();
}
view = view.parentView;
}
};
Example usage: someTemplate.parentTemplate() to get the immediate parent
Is there a clean way to get the parent template of the current
template?
Currently, none that I know of, but this is supposed to happen sometime in the future as part of a planned "better API for designing reusable components" (this is discussed in the Meteor post 1.0 roadmap).
For the moment, here is a workaround I'm using in my projects :
// extend Blaze.View prototype to mimick jQuery's closest for views
_.extend(Blaze.View.prototype,{
closest:function(viewName){
var view=this;
while(view){
if(view.name=="Template."+viewName){
return view;
}
view=view.parentView;
}
return null;
}
});
// extend Blaze.TemplateInstance to expose added Blaze.View functionalities
_.extend(Blaze.TemplateInstance.prototype,{
closestInstance:function(viewName){
var view=this.view.closest(viewName);
return view?view.templateInstance():null;
}
});
Note that this is only supporting named parent templates and supposed to work in the same fashion as jQuery closest to traverse parent views nodes from a child to the top-most template (body), searching for the appropriately named template.
Once this extensions to Blaze have been registered somewhere in your client code, you can do stuff like this :
HTML
<template name="parent">
<div style="background-color:{{backgroundColor}};">
{{> child}}
</div>
</template>
<template name="child">
<button type="button">Click me to change parent color !</button>
</template>
JS
Template.parent.created=function(){
this.backgroundColor=new ReactiveVar("green");
};
Template.parent.helpers({
backgroundColor:function(){
return Template.instance().backgroundColor.get();
}
});
Template.child.events({
"click button":function(event,template){
var parent=template.closestInstance("parent");
var backgroundColor=parent.backgroundColor.get();
switch(backgroundColor){
case "green":
parent.backgroundColor.set("red");
break;
case "red":
parent.backgroundColor.set("green");
break;
}
}
});
What I've been doing so far is that if I need to access the parent instance in a child template's function, I try to instead refactor this function to declare it on the parent template, and then pass it as argument to the child, who can then execute it.
As an example, let's say I want to increment a template variable on the parent template from within the child template. I could write something like this:
Template.parentTemplate.onCreated(function () {
var parentInstance = this;
parentInstance.count = new ReactiveVar(1);
});
Template.parentTemplate.helpers({
incrementHandler: function () {
var parentInstance = Template.instance();
var count = parentInstance.count.get();
return function () {
var newCount = count + 1;
parentInstance.count.set(newCount);
};
}
});
Then include my child template:
{{> childTemplate handler=loadMoreHandler}}
And set up my event:
Template.childTemplate.events({
'click .increment-button': function (event, childInstance) {
event.preventDefault();
childInstance.data.handler();
}
});
If you don't want to extend Blaze.TemplateInstance you can access the parent instance like this:
Template.exampleTemplate.onRendered(function () {
const instance = this;
const parentInstance = instance.view.parentView.templateInstance();
});
Only tested in Meteor 1.4.x
You can use a package like Aldeed's template-extension
The following method is available there:
templateInstance.parent(numLevels, includeBlockHelpers)
I have the following template:
<template name="modalTest">
{{session "modalTestNumber"}} <button id="modalTestIncrement">Increment</button>
</template>
That session helper simply is a go-between with the Session object. I have that modalTestNumber initialized to 0.
I want this template to be rendered, with all of it's reactivity, into a bootbox modal dialog. I have the following event handler declared for this template:
Template.modalTest.events({
'click #modalTestIncrement': function(e, t) {
console.log('click');
Session.set('modalTestNumber', Session.get('modalTestNumber') + 1);
}
});
Here are all of the things I have tried, and what they result in:
bootbox.dialog({
message: Template.modalTest()
});
This renders the template, which appears more or less like 0 Increment (in a button). However, when I change the Session variable from the console, it doesn't change, and the event handler isn't called when I click the button (the console.log doesn't even happen).
message: Meteor.render(Template.modalTest())
message: Meteor.render(function() { return Template.modalTest(); })
These both do exactly the same thing as the Template call by itself.
message: new Handlebars.SafeString(Template.modalTest())
This just renders the modal body as empty. The modal still pops up though.
message: Meteor.render(new Handlebars.SafeString(Template.modalTest()))
Exactly the same as the Template and pure Meteor.render calls; the template is there, but it has no reactivity or event response.
Is it maybe that I'm using this less packaging of bootstrap rather than a standard package?
How can I get this to render in appropriately reactive Meteor style?
Hacking into Bootbox?
I just tried hacked into the bootbox.js file itself to see if I could take over. I changed things so that at the bootbox.dialog({}) layer I would simply pass the name of the Template I wanted rendered:
// in bootbox.js::exports.dialog
console.log(options.message); // I'm passing the template name now, so this yields 'modalTest'
body.find(".bootbox-body").html(Meteor.render(Template[options.message]));
body.find(".bootbox-body").html(Meteor.render(function() { return Template[options.message](); }));
These two different versions (don't worry they're two different attempts, not at the same time) these both render the template non-reactively, just like they did before.
Will hacking into bootbox make any difference?
Thanks in advance!
I am giving an answer working with the current 0.9.3.1 version of Meteor.
If you want to render a template and keep reactivity, you have to :
Render template in a parent node
Have the parent already in the DOM
So this very short function is the answer to do that :
renderTmp = function (template, data) {
var node = document.createElement("div");
document.body.appendChild(node);
UI.renderWithData(template, data, node);
return node;
};
In your case, you would do :
bootbox.dialog({
message: renderTmp(Template.modalTest)
});
Answer for Meteor 1.0+:
Use Blaze.render or Blaze.renderWithData to render the template into the bootbox dialog after the bootbox dialog has been created.
function openMyDialog(fs){ // this can be tied to an event handler in another template
<! do some stuff here, like setting the data context !>
bootbox.dialog({
title: 'This will populate with content from the "myDialog" template',
message: "<div id='dialogNode'></div>",
buttons: {
do: {
label: "ok",
className: "btn btn-primary",
callback: function() {
<! take some actions !>
}
}
}
});
Blaze.render(Template.myDialog,$("#dialogNode")[0]);
};
This assumes you have a template defined:
<template name="myDialog">
Content for my dialog box
</template>
Template.myDialog is created for every template you're using.
$("#dialogNode")[0] selects the DOM node you setup in
message: "<div id='dialogNode'></div>"
Alternatively you can leave message blank and use $(".bootbox-body") to select the parent node.
As you can imagine, this also allows you to change the message section of a bootbox dialog dynamically.
Using the latest version of Meteor, here is a simple way to render a doc into a bootbox
let box = bootbox.dialog({title:'',message:''});
box.find('.bootbox-body').remove();
Blaze.renderWithData(template,MyCollection.findOne({_id}),box.find(".modal-body")[0]);
If you want the dialog to be reactive use
let box = bootbox.dialog({title:'',message:''});
box.find('.bootbox-body').remove();
Blaze.renderWithData(template,function() {return MyCollection.findOne({_id})},box.find(".modal-body")[0]);
In order to render Meteor templates programmatically while retaining their reactivity you'll want to use Meteor.render(). They address this issue in their docs under templates.
So for your handlers, etc. to work you'd use:
bootbox.dialog({
message: Meteor.render(function() { return Template.modalTest(); })
});
This was a major gotcha for me too!
I see that you were really close with the Meteor.render()'s. Let me know if it still doesn't work.
This works for Meteor 1.1.0.2
Assuming we have a template called changePassword that has two fields named oldPassword and newPassword, here's some code to pop up a dialog box using the template and then get the results.
bootbox.dialog({
title: 'Change Password',
message: '<span/>', // Message can't be empty, but we're going to replace the contents
buttons: {
success: {
label: 'Change',
className: 'btn-primary',
callback: function(event) {
var oldPassword = this.find('input[name=oldPassword]').val();
var newPassword = this.find('input[name=newPassword]').val();
console.log("Change password from " + oldPassword + " to " + newPassword);
return false; // Close the dialog
}
},
'Cancel': {
className: 'btn-default'
}
}
});
// .bootbox-body is the parent of the span, so we can replace the contents
// with our template
// Using UI.renderWithData means we can pass data in to the template too.
UI.insert(UI.renderWithData(Template.changePassword, {
name: "Harry"
}), $('.bootbox-body')[0]);
I have a small doubt,Is it possible to change the template helper data dynamically.
Here is my template
{{#each post}}
<h4>{{postyname}}</h4>
<h4>{{Headline}}</h4>
<h4>{{Location}}</h4>
{{/each}}
and this is my helper data
post:function()
{
posts.find({},{sort: {createdAt: -1}}).fetch();
}
and it is displaying results in my homepage and i have search bar at the top of this page and whenever user clicks search button the same template must be render but with different data depend on user search.
I've tried like this on my onclick event,looks like it is not working
'onclick #searchBtn':function()
{
var all_posts=posts.find({'Headline': search},{sort: {createdAt: -1}}).fetch();
Template.postDisplay.post=function(){
return all_posts;
}
How to do this?
I believe using Dep Dependency is what you want to use:
Create a variable on the top of your js file
var _deps = new Tracker.Dependency;
var searchCriteria = {};
In your helper:
post:function() {
_deps.depend(); // creates a dependency between the accessor of "post" and the _deps
posts.find(searchCriteria,{sort: {createdAt: -1}}).fetch();
}
On your button click:
'onclick #searchBtn':function() {
searchCriteria = {'Headline': search};
_deps.changed(); // notifying everyone that is dependent on _deps that it has changes
}
Based on what I see from your question I believe this should handle your situation. Let me know if I misunderstood something in your problem.
Why not just use a Session variable? They are reactive, just what you need.
Instead of manually handling a dependency, using Session.set and Session.get will register and fire dependencies automatically..
post:function()
{
var searchCriteria = Session.get("searchCriteria") || {};
posts.find(searchCriteria,{sort: {createdAt: -1}}).fetch();
}
'onclick #searchBtn':function()
{
Session.set("searchCriteria", {'Headline': search});
}
The Session variable would also be preserved after a hot code reload. A variable would not.