I am new to development in Angular2 - Meteor. I have stumbled upon a problem while working with parent-child components. In the parent component, I have meteor subscribing to a collection.
users: any;
constructor(private _zone:NgZone){
var sub = Meteor.subscribe("accounts/users");
Tracker.autorun(function() {
_zone.run(function() {
if(sub.ready()){
this.users = Meteor.users.find().fetch();
console.log(this.users);
}
});
});
}
The user collection has 90 users in total. When the app initially loads, only the current user is found, thus the console log shows one user.
I am not sure if my placement of Tracker.autorun() and NgZone are correct, but after a second of the app loading, the console log shows an array of all 90 users. I assume this happens because the subscribe is not ready at first.
My child component takes in the fetched users as a parameter like this <sd-table [data]="users"></sd-table>. Upon loading of the application, there is only one user that is seen on the drawn template of the child component. Is there any way that the template can be updated when the subscribe happens and all users become accessible?
If you want to refer to this of the current class, don't use function()
users: any;
constructor(private _zone:NgZone){
var sub = Meteor.subscribe("accounts/users");
Tracker.autorun(() => {
_zone.run(() => {
if(sub.ready()){
this.users = Meteor.users.find().fetch();
console.log(this.users);
}
});
});
}
https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Functions/Arrow_functions
Related
I prepared a boiled-down example on stackblitz:
https://stackblitz.com/edit/quasarframework-vy4eiw?file=README.md
The problem I try to resolve is this:
A quasar 2 app build with vite and vue 3 (and GSAP) uses layouts
Currently there are 2 layouts: StartpageLayout for the startpage at route ´/´and MainpageLayout for all the other pages at route ´/main´ and any children of it (/main/:child´`)
The MainpageLayout also contains the navigation menu
The navigation menu should be created (later on with an animation) when any route starting with ´/main´ is hit and destroyed, when there is a change to any other route
While navigating through any ´/main[/:child]´ route, the nav menu shall remain "stable" (not rebuild or anything like that)
The app uses 2 router-views for this, one in App.vue, one in MainLayout.vue. Changes between those states should mainly be handled in onBeforeRouteLeave and onBeforeRouteUpdate
To check, whether the app is in a "layout context", the routes have a meta.layoutKey, which is used in router guards to check, whether sth changed or not:
// Example: src/layouts/MainLayout.vue
onBeforeRouteUpdate((to, from, next) => {
console.log('%cMAIN_LAYOUT: onBeforeRouteUpdate invoked', consColRouter);
// compare meta.layoutKeys of routes
if (from.meta.layoutKey !== to.meta.layoutKey) {
console.warn(' YES, invoke router guard onBeforeRouteUpdate - animate!');
next() // this would be actually be called form an onComplete animation callback
} else {
console.log(' NOPE, do not invoke router guard onBeforeRouteUpdate');
next() // invoked as written
}
})
A pinia store manages state that (should) remember(s) activateMenu:
// Pinia store "pageTransitions.js" (composition API)
import { ref, reactive, computed } from 'vue'
import { defineStore } from 'pinia'
export const usePageTransitionsStore = defineStore('pageTransitions', () => {
// Pinia state in composition API
const pageTransitions = ref({
parent: false,
activateMenu: false
})
const setPageTransitions = (level, bool) => {
switch(level) {
case 'parent': {
pageTransitions.value.parent = bool
break
}
default: { console.log('default... must never happen!'); }
}
}
const setActivateMenu = (bool) => {
pageTransitions.value.activateMenu = bool
}
return {
pageTransitions,
setPageTransitions,
setActivateMenu
}
})
If store.pageTransitions.activateMenu is true, show the menu, if false, remove it. It is imported in MainLayout in order to use the activateMenu constant to manage the state of the nav menu. The onMount method sets this store variable to true. And it should be set to false in a ònBeforeRouteLeave`... (not yet implemented)
While the change from the startpage at ´/´to the MainPage at ´/main´ and vice versa works fine (even with animation, due to the store variable store.pageTransitions.parent), I keep having troubles with changes from ´/main´ to any child route ´/main/:child´ and vice versa. E.g. when the app is at /main and the user clicks on ´items 101´, the whole MainLayout is reloaded - also App.vue runs through its onAppear hooks again (see console) – and the nav is set to false again.
The goal is to not influence the MainLayout not its nested nav menu at all.
I wonder, why those reloads happen? MainLayout's onBeforeRoute checks against meta.layoutKey which does not change. But then I also observe that the pinia store gets loaded again, and the actiavteMenu var is set up false again...
Does anybody see my error(s)?
Ok, I believe I am VERY close to having my first working Vue JS application but I keep hitting little snag after little snag. I hope this is the last little snag.
I am using vue-async-computed and axios to fetch a customer object from my API.
I am then passing that property to a child component and rendering to screen like: {{customer.fName}}.
As far as I can see, the ajax call is being made and the response coming back is expected, the problem is there is nothing on the page, the customer object doesnt seem to update after the ajax call maybe.
Here is the profile page .vue file I'm working on
http://pastebin.com/DJH9pAtU
The component has a computed property called "customer" and as I said, I can see in the network tab, that request is being made and there are no errors. The response is being sent to the child component here:
<app-customerInfo :customer="customer"></app-customerInfo>
within that component I am rendering the data to the page:
{{customer.fName}}
But, the page shows no results. Is there a way to verify the value of the property "customer" in inspector? is there something obvious I am missing?
I've been using Vue for about a year and a half, and I realize the struggle that is dealing with async data loading and that good stuff. Here's how I would set up your component:
<script>
export default {
components: {
// your components were fine
},
data: () => ({ customer: {} }),
async mounted() {
const { data } = await this.axios.get(`/api/customer/get/${this.$route.params.id}`);
this.customer = data;
}
}
</script>
so what I did was initialize customer in the data function for your component, then when the component gets mounted, send an axios call to the server. When that call returns, set this.customer to the data. And like I said in my comment above, definitely check out Vue's devtools, they make tracking down variables and events super easy!
I believed your error is with naming. The vue-async-computed plugin needs a new property of the Vue object.
computed: {
customer: async function() {
this.axios.get('/api/customer/get/' + this.$route.params.id).then(function(response){
return(response.data);
});
}
}
should be:
asyncComputed: {
async customer() {
const res = await this.axios.get(`/api/customer/get/${this.$route.params.id}`);
return res.data;
}
}
I have a parent/child component setup where the parent is loading data from the server and passing it down to children via props. In the child I would like to instantiate a jQuery calendar with some of the data it receives from the parent.
In order to wait for the data before setting up the calendar, I broadcast an event in the parent that I have an event listener setup for in the child.
The listener is being fired in the child but if I this.$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 need to pass value from tabs.ts to each page of tabs. So I have something like this:
constructor(public navParams: NavParams) {
...// config
firebase.auth().onAuthStateChanged((user) => {
if (user) {
// If there's a user take him to the home page.
this.user = [];
this.user.push(user);
this.rootPage = HomePage;
} else {
// If there's no user logged in send him to the LoginPage
this.rootPage = LoginPage;
}
});
}
this.tab1Root = HomePage;
this.tab4Root = ProfilePage;
How to pass value (user) to each page of tabs? I tried with few combinations of this code but doesnt work (getting some erros - e.g If I put this.tab1Root... to onAuthStateChanged method, then it gives me: "Maximum call stack size exceeded"). Here are docs: http://ionicframework.com/docs/v2/api/components/tabs/Tab/ - I understand 90% of this but still dont know how I should pass this value...
My second question - is there any better way to take current user and pass him as value to each page? Will be better if I use provider or something?
Third question: it is good to have this code in tabs.ts than in app.ts?
Thanks!
You can use [rootParams] attribute in ion-tab
<ion-tab ... [rootParams]="user"></ion-tab>
In tab file:
constructor(navParams: NavParams) {
console.log("Passed params", navParams.data.user);
}
Second way is using events: http://ionicframework.com/docs/v2/api/util/Events/
It allows you to share data between any of your pages.
Provider is a good option.
It depends. Better way is to make an authorization once - using provider inside app.ts - when app starts.
How to update a single object within node.
{
foo:
{
title: 'hello world',
time: '1000'
}
}
As above, I just want update title.
$firebase(new Firebase(ref).child('foo')).$save(); will update the entire node. Also tried $save('title') but not work.
The reason I just want to update a single object, because some of the ng-model doesn't need to update to firebase.
Heres an example setting the title to "whatever"
$firebase(new Firebase(ref)).$child('foo').$child('title').$set("whatever")
I have recently been working with angularfire and firebase. I am not sure if this is a fix but i dont think you dont need to explicitly select the item property you want to update when you are using the $save() method.
For instance, in my use case i was selecting a user and had an init function that got that whole object
html
<ul ng-repeat="user in vm.users>
<button ng-click="vm.updateUserInit(user)">Edit</button>
</ul>
This then opened up the update form with the users properties. In the controller i took that user and assigned it into a $firebaseObject.
controller
var selectedUser;
vm.updateUserInit = function (user) {
var ref = new Firebase("https://<foo>.firebaseio.com/users/" + user.$id);
selectedUser = $firebaseObject(ref);
}
It justs puts the user into a firebase object as the variable selectedUser to use in the $save.
Then when the user updates the details
html
<button type="button" ng-click="vm.updateUserDetails()">Update User Details</button>
the function already has the selected user as an object to use and anything added will be updated. Anything omitted will not.
controller
vm.updateUserDetails = function () {
selectedUser.firstName = vm.firstName;
selectedUser.$save();
}
The selectedUser.$save(); changes only the first name even though the user has 6 other properties
Not sure if this helps, trying to wrap my head around all of this as well. Check out valcon if you dont already have it. Really nice extension on the chrome inspector for firebase
UPDATE FOR ANGULARFIRE 2
if you create a service for your calls , which could serve all update calls
constructor(private db: AngularFireDatabase) {}
update(fbPath: string, data: any) {
return this.db.object(fbPath).update(data);
}
And then in the page component
this.api.update(`foo`, ({ title: 'foo Title' }) );
Much simpler