Ok I'm a beginner at VueJS and I'm just trying to do a simple XHR call and bind the json data response to my variable...
I have a component App.vue and this part of the template I want to show the results of the json. bpi is the name of the variable
<div id="simulationPoints">
<h2 className="logTitle">Full Log:</h2>
{{ bpi }}
</div>
then my script
export default {
name: 'App',
data: () => ({
bpi: []
}),
mounted: () => {
axios.get(`https://api.coindesk.com/v1/bpi/historical/close.jsonp?start=2011-01-01&end=2018-02-01`)
.then(response => {
this.bpi = response.data.bpi
})
.catch(e => {
this.errors.push(e)
})
}
}
This doesn't seem to work. I'm using Axiom to fetch the data and assign the response, and this is how all the examples I found online did it, but the array object I have is still empty and it doesn't render on the page. I don't know whats the issue here? A Vue expert please help :)
There are sorts of problem in your code.
First, don't use arrow function on options property or callback since arrow functions are bound to the parent context, this will not be the Vue instance as you’d expect.
Second, use return statement in your data function.
Third, use created hook for inserting data after instance is created. mounted hook is called for mutation after DOM is rendered.
export default {
name: 'App',
data: function() {
return {
bpi: []
}
},
created() {
axios.get(`https://api.coindesk.com/v1/bpi/historical/close.jsonp?start=2011-01-01&end=2018-02-01`)
.then(response => {
this.bpi = response.data.bpi
})
.catch(e => {
this.errors.push(e)
})
}
}
Related
I've a hard time in understanding the methods of vue. In my put-request users can edit, delete images. In parent component the get-request loads the images and the are pushed to an image-gallery (the child-component) via properties. In my set up the console.log is always empty.
//PARENT COMPONENT
<template>
<div class="form-group">
<image-gallery :serverData="serverMap"/>
</div>
</template>
<script>
import ImageGallery from './ImageGallery.vue';
export default {
components:{ImageGallery},
data: () => ({
serverMap: {
title: '',
file: ''
}
}),
mounted () {
//AJAX ETC get servermap
.then((response) => {
this.serverMap = response.data
})
}
Just a normal straight parent-child situation. Here under the child-component
<template>
</template>
<script>
export default {
name: 'ImageGallery',
//incoming data
props: {
serverData: {
type: Object,
default () {
return {
hasLabels: true,
isHorizontal: false
}
}
}
},
created: function () {
this.loadImages()
},
methods: {
loadImages () {
console.log(this.serverData.file)
//do something with the serverData
//prepare for fileReader function
//together with new image validation
}
}
The method 'loadImages' should be automatically delevering the serverData via computed.But is doesn t. Who can help?
There is race condition.
Either not render a child until data is available; serverMap needs to be null instead of empty object in order to be distinguished from populated object:
<image-gallery v-if="serverMap" :serverData="serverMap"/>
Or delay data access in a child until it's available instead of doing this immediately in created:
watch: {
serverData(data) {
if (data)
this.loadImages()
}
}
countSubcategories() function returns [object Promise] where it should return row counts of mapped subcategories.
This code is in vue.js & Laravel, Any suggestions on this?
<div v-for="(cat,index) in cats.data" :key="cat.id">
{{ countSubcategories(cat.id) }} // Here subcategories row counts should be displayed.
</div>
<script>
export default {
data() {
return {
cats: {},
childcounts: ""
};
},
created() {
this.getCategories();
},
methods: {
countSubcategories(id) {
return axios
.get("/api/user-permission-child-count/" + `${id}`)
.then(response => {
this.childcounts = response.data;
return response.data;
});
},
getCategories(page) {
if (typeof page === "undefined") {
page = 1;
}
let url = helper.getFilterURL(this.filterpartnerForm);
axios
.get("/api/get-user-permission-categories?page=" + page + url)
.then(response => (this.cats = response.data));
}
}
};
</script>
As Aron stated in the previous answer as you are calling direct from the template the information is not ready when the template is rendered.
As far as I understood you need to run getCategories first so then you can fetch the rest of your data, right?
If that's the case I have a suggestion:
Send an array of cat ids to your back-end and there you could send back the list of subcategories you need, this and this one are good resources so read.
And instead of having 2 getCategories and countSubcategories you could "merge" then like this:
fetchCategoriesAndSubcategories(page) {
if (typeof page === "undefined") {
page = 1;
}
let url = helper.getFilterURL(this.filterpartnerForm);
axios
.get("/api/get-user-permission-categories?page=" + page + url)
.then(response => {
this.cats = response.data;
let catIds = this.cats.map(cat => (cat.id));
return this.countSubcategories(catIds) // dont forget to change your REST endpoint to manage receiving an array of ids
})
.then(response => {
this.childcounts = response.data
});
}
Promises allow you to return promises within and chain .then methods
So in your created() you could just call this.fetchCategoriesAndSubcategories passing the data you need. Also you can update your template by adding a v-if so it doesn't throw an error while the promise didn't finish loading. something like this:
<div v-if="childCounts" v-for="(subcategorie, index) in childCounts" :key="subcategorie.id">
{{ subcategorie }} // Here subcategories row counts should be displayed.
</div>
Hello!
Based on the provided information, it could be 2 things. First of all, you may try replacing:
return response.data;
with:
console.log(this.childcounts)
and look in the console if you have the correct information logged. If not, it may be the way you send the information from Laravel.
PS: More information may be needed to solve this. When are you triggering the 'countSubcategories' method?
I would do all the intial login in the component itself, and not call a function in template like that. It can drastically affect the performance of the app, since the function would be called on change detection. But first, you are getting [object Promise], since that is exactly what you return, a Promise.
So as already mentioned, I would do the login in the component and then display a property in template. So I suggest the following:
methods: {
countSubcategories(id) {
return axios.get("..." + id);
},
getCategories(page) {
if (typeof page === "undefined") {
page = 1;
}
// or use async await pattern
axios.get("...").then(response => {
this.cats = response.data;
// gather all nested requests and perform in parallel
const reqs = this.cats.map(y => this.countSubcategories(y.id));
axios.all(reqs).then(y => {
// merge data
this.cats = this.cats.map((item, i) => {
return {...item, count: y[i].data}
})
});
});
}
}
Now you can display {{cat.count}} in template.
Here's a sample SANDBOX with similar setup.
This is happen 'cause you're trying to render a information who doesn't comeback yet...
Try to change this method inside created, make it async and don't call directly your method on HTML. Them you can render your variable this.childcounts.
I am trying to show client information details in the modal. After clicking #click="showDetails(props.row.id)".
I am using axios.get in method and returning the data. Now, It's returning the data as PromiseValue object. How to access PromiseValue to show the value in HTML. Would someone help me please to solve the problem! I am trying like below -
<button #click="showDetails(props.row.id)"><i class="fas fa-eye"></i></button>
And in script-
<script type="text/javascript">
import axios from 'axios';
export default {
data(){
return{
leftPanelVisiblity: false,
singleData: '', }
},
methods:{
showDetails(id){
let b = axios.get('/api/clients/'+id)
.then(function (response) {
return response.data;
}).catch(error => {
alert(error);
});
//console.log(b);
this.singleData = b;
this.leftPanelVisiblity = true
},
}
}
</script>
And finally, I want to access or show the data in the leftPanelVisiblity modal like -
<p>Name: {{ this.singleData.name }}</p>
Or
<p>Name: {{ this.singleData.email }}</p>.
You cannot assign the Axios call to a variable while using Promises (unless you are using await/async).
Instead you should be running the logic within the then callback. Otherwise to the synchronous nature of JavaScript it will run before the request has completed. Your code should look something like this:
methods:{
showDetails(id){
axios.get('/api/clients/'+row.id).then(response => {
//Logic goes here
this.singleData = response.data
this.leftPanelVisibility = true
}).catch(error => {
alert(error);
});
}
}
You need to assign a variable the response of your axios:
showDetails(id){
axios.get('/api/clients/'+id)
.then(function (response) {
this.singleData = response.data;
}).catch(error => {
alert(error);
});
console.log(this.sigleData);
this.leftPanelVisiblity = true
},
I have app.js importing axios and VueAxios as:
Vue.use(VueAxios, axios);
Then calling my component:
Vue.component('api-call', require('./components/PostComponent'));
In my PostComponent I have a simple axios get as follows:
<script>
export default {
// name: "PostComponent"
data() {
return {
post: {},
}
},
methods: {
getPosts: () => {
console.log('started');
//let that = this;
let uri = 'https://jsonplaceholder.typicode.com/posts';
this.axios.get(uri).then((response) => {
console.log(response);
})
}
},
mounted(){
this.getPosts()
}
}
</script>
Since I want this executed right at the start of the component loading I am using mounted (why Vue don't have a constructor baffles me, even react passed on the isMounted pattern.)
What am I doing wrong?
thanks,
Bud
You can't use arrow function for methods declaration.
See https://v2.vuejs.org/v2/api/#methods
Note that you should not use an arrow function to define a method
(e.g. plus: () => this.a++). The reason is arrow functions bind the
parent context, so this will not be the Vue instance as you expect and
this.a will be undefined.
These are the 2 ways to properly define a method
1.
getPosts: function() {
}
(if you can use ES6)
getPosts() {
}
I may be wrong in my understanding of props but I can't seem to be able to pass a prop to a component and then use the value in a method?
So far I am able to get data from a fixed API and output everything from the vue component, now I would like the api source to be dependent on the variable passed to the component.
My blade template:
<projectstatuses :userslug="this-user" :projectslug="this-project"></projectstatuses>
Then in my Vue Component:
export default {
props: {
userslug: {
type: String,
default: "other-user",
},
projectslug: {
type: String,
default: "other-project",
}
},
data() {
return {
statuses : [],
}
},
created(){
this.getStatuses();
},
methods : {
getStatuses(){
console.log(this.userslug);
console.log(this.projectslug);
axios.get('/api/' + this.userslug + '/' + this.projectslug)
.then((response) => {
let statuses = response.data;
this.statuses = statuses.statuses;
console.log(response.data.statuses);
})
.catch(
(response) => {
console.log('error');
console.log(response.data);
}
);
}
}
}
In the console I get the default values, if I remove the default values I get undefined. I have tried removing the api method and simply console logging the values but I still get undefined. Is what I'm trying to do possible or have I completely misunderstood how props work?
You are trying to bind this-user and this-project as a properties not as values ,
So you will need to define them in the data object in the parent,
but if you want to pass this-user and this-project just as value remove the : try that:
<projectstatuses userslug="this-user" projectslug="this-project"></projectstatuses>
Dynamic-Props
Don't add : in your template:
<projectstatuses userslug="this-user" projectslug="this-project"></projectstatuses>
Vue will expect there's data bound to this-user.