How Can Show Variable in Page if its on onchange Method. for Example this Code:
methods: {
onChange(image) {
if (image) {
EXIF.getData(this.$refs.pictureInput.file, function () {
var make = EXIF.getTag(this, "Make"),
model = EXIF.getTag(this, "Model");
})
} else {
console.log(`it's not image`)
}
},
}
I want show make and model variable to User.
To access the this of a component inside another scope, (in your case your EXIF callback) just create a new reference to the component's this in the higher scope and access it inside the callback function.
export default {
data () {
return {
name: '',
model: ''
}
},
methods: {
onChange(image) {
const component = this;
if (image) {
EXIF.getData(this.$refs.pictureInput.file, function () {
var make = EXIF.getTag(this, "Make"),
model = EXIF.getTag(this, "Model");
component.make = make;
component.model = model;
})
} else {
console.log(`it's not image`)
}
}
}
}
Now inside your template:
<template>
<div>
<span>Name: {{name}}</span>
<span>Model: {{model}}</span>
</div>
</template>
Related
In my VueJS 2 component below, I can add the imgdata property to each question in the area.questions array. It works - I can see from the console.log that there are questions where imgdata has a value. But despite using $set it still isn't reactive, and the imgdata isn't there in the view! How can I make this reactive?
var componentOptions = {
props: ['area'],
data: function() {
return {
qIndex: 0,
};
},
mounted: function() {
var that = this;
that.init();
},
methods: {
init: function() {
var that = this;
if (that.area.questions.length > 0) {
that.area.questions.forEach(function(q) {
Util.HTTP('GET', '/api/v1/photos/' + q.id + '/qimage').then(function(response) {
var thisIndex = (that.area.questions.findIndex(entry => entry.id === q.id));
var thisQuestion = (that.area.questions.find(entry => entry.id === q.id));
thisQuestion.imgdata = response.data;
that.$set(that.area.questions, thisIndex, thisQuestion);
})
});
}
console.log("area.questions", that.area.questions);
},
Since area is a prop, you should not be attempting to make changes to it within this component.
The general idea is to emit an event for the parent component to listen to in order to update the data passed in.
For example
export default {
name: "ImageLoader",
props: {
area: Object
},
data: () => ({ qIndex: 0 }), // are you actually using this?
mounted () {
this.init()
},
methods: {
async init () {
const questions = await Promise.all(this.area.questions.map(async q => {
const res = await Util.HTTP("GET", `/api/v1/photos/${encodeURIComponent(q.id)}/qimage`)
return {
...q,
imgdata: res.data
}
}))
this.$emit("loaded", questions)
}
}
}
And in the parent
<image-loader :area="area" #loaded="updateAreaQuestions"/>
export default {
data: () => ({
area: {
questions: [/* questions go here */]
}
}),
methods: {
updateAreaQuestions(questions) {
this.area.questions = questions
}
}
}
Here that variable has a value of this but it's bound under the scope of function. So, you can create reactive property in data as below :
data: function() {
return {
qIndex: 0,
questions: []
};
}
Props can't be reactive so use :
that.$set(this.questions, thisIndex, thisQuestion);
And assign your API output to directly questions using this.questions.
I'm new in Vue and would like assistance on how to access and use variables created in Mounted() in my methods.
I have this code
Template
<select class="controls" #change="getCatval()">
Script
mounted() {
var allcards = this.$refs.allcards;
var mixer = mixitup(allcards);
},
methods: {
getCatval() {
var category = event.target.value;
// I want to access mixer here;
}
}
I can't find a solution anywhere besides this example where I could call a method x from mounted() and pass mixer to it then use it inside my getCatval()
Is there an easier way to access those variables?
I will first suggest you to stop using var, and use the latest, let and const to declare variable
You have to first declare a variable in data():
data(){
return {
allcards: "",
mixer: ""
}
}
and then in your mounted():
mounted() {
this.allcards = this.$refs.allcards;
this.mixer = mixitup(this.allcards);
},
methods: {
getCatval() {
let category = event.target.value;
this.mixer
}
}
like Ninth Autumn said : object returned by the data function and props of your components are defined as attributes of the component, like your methods defined in the method attribute of a component, it's in this so you can use it everywhere in your component !
Here an example:
data() {
return {
yourVar: 'hello',
};
},
mounted() { this.sayHello(); },
method: {
sayHello() { console.log(this.yourVar); },
},
Update
you cannot pass any value outside if it's in block scope - Either you need to get it from a common place or set any common value
As I can see, var mixer = mixitup(allcards); is in the end acting as a function which does some operation with allcards passed to it and then returns a value.
1 - Place it to different helper file if mixitup is totally independent and not using any vue props used by your component
In your helper.js
const mixitup = cards => {
// Do some operation with cards
let modifiedCards = 'Hey I get returned by your function'
return modifiedCards
}
export default {
mixitup
}
And then in your vue file just import it and use it is as a method.
In yourVue.vue
import Helpers from '...path../helpers'
const mixitup = Helpers.mixitup
export default {
name: 'YourVue',
data: ...,
computed: ...,
mounted() {
const mixer = mixitup(allcards)
},
methods: {
mixitup, // this will make it as `vue` method and accessible through
this
getCatval() {
var category = event.target.value;
this.mixitup(allcards)
}
}
}
2- Use it as mixins if your mixitup dependent to your vue and have access to vue properties
In your yourVueMixins.js:
export default {
methods: {
mixitup(cards) {
// Do some operation with cards
let modifiedCards = 'Hey I get returned by your function'
return modifiedCards
}
}
}
And import it in your vue file:
import YourVueMixins from '...mixins../YourVueMixins'
const mixitup = Helpers.mixitup
export default {
name: 'YourVue',
mixins: [YourVueMixins] // this will have that function as vue property
data: ...,
computed: ...,
mounted() {
const mixer = this.mixitup(allcards)
},
methods: {
getCatval() {
var category = event.target.value;
this.mixitup(allcards)
}
}
}
I'm trying to implement the following logic in Nuxt:
Ask user for an ID.
Retrieve a URL that is associated with that ID from an external API
Store the ID/URL (an appointment) in Vuex
Display to the user the rendered URL for their entered ID in an iFrame (retrieved from the Vuex store)
The issue I'm currently stuck with is that the getUrl getter method in the store is called repeatedly until the maximum call stack is exceeded and I can't work out why. It's only called from the computed function in the page, so this implies that the computed function is also being called repeatedly but, again, I can't figure out why.
In my Vuex store index.js I have:
export const state = () => ({
appointments: {}
})
export const mutations = {
SET_APPT: (state, appointment) => {
state.appointments[appointment.id] = appointment.url
}
}
export const actions = {
async setAppointment ({ commit, state }, id) {
try {
let result = await axios.get('https://externalAPI/' + id, {
method: 'GET',
protocol: 'http'
})
return commit('SET_APPT', result.data)
} catch (err) {
console.error(err)
}
}
}
export const getters = {
getUrl: (state, param) => {
return state.appointments[param]
}
}
In my page component I have:
<template>
<div>
<section class="container">
<iframe :src="url"></iframe>
</section>
</div>
</template>
<script>
export default {
computed: {
url: function (){
let url = this.$store.getters['getUrl'](this.$route.params.id)
return url;
}
}
</script>
The setAppointments action is called from a separate component in the page that asks the user for the ID via an onSubmit method:
data() {
return {
appointment: this.appointment ? { ...this.appointment } : {
id: '',
url: '',
},
error: false
}
},
methods: {
onSubmit() {
if(!this.appointment.id){
this.error = true;
}
else{
this.error = false;
this.$store.dispatch("setAppointment", this.appointment.id);
this.$router.push("/search/"+this.appointment.id);
}
}
I'm not 100% sure what was causing the multiple calls. However, as advised in the comments, I've now implemented a selectedAppointment object that I keep up-to-date
I've also created a separate mutation for updating the selectedAppointment object as the user requests different URLs so, if a URL has already been retrieved, I can use this mutation to just switch the selected one.
SET_APPT: (state, appointment) => {
state.appointments = state.appointments ? state.appointments : {}
state.selectedAppointment = appointment.url
state.appointments = { ...state.appointments, [appointment.appointmentNumber]: appointment.url }
},
SET_SELECTED_APPT: (state, appointment) => {
state.selectedAppointment = appointment.url
}
Then the getUrl getter (changed its name to just url) simply looks like:
export const getters = {
url: (state) => {
return state.selectedAppointment
}
}
Thanks for your help guys.
When I get data from the server, like
[{methodName:mothodValue},{methodName:mothodValue}]
then I want dynamic generation method, like
methods: {
functionArray.forEach(function (item) {
item.functionName:function () {
item.functionValue;
}
})
}
so this is my code
var componentName = Vue.component(componentName, {
data: function () {
return {
value: value
}
},
template: componentTemplate,
methods:{
functionArray.forEach(function (item) {
item.functionName:function () {
item.functionValue;
}
})
}
})
the old code was
methods:{
getValue : function(){
getValue(this.value);
}
}
Is that possible?
If the data from the server is returned before the creation of the Vue component (I'm not sure if you can add methods after the creation of a Vue component), then you can create a methods object like so:
var methods = {};
functionArray.forEach(function (item) {
methods[item.functionName] = item.functionValue;
});
You can't populate an object literal with code, but you can populate an empty object literal afterwards with code like so.
Then you can put it into your component like so:
var componentName = Vue.component(componentName, {
// ..
methods: methods
});
How to pass a variable from a function in the component in Vue?
This is my code:
export default {
name: 'app',
data: function () {
return{
city1: '',
city2: '',
metr: 0
}
},
created () {
ymaps.ready(init);
function init() {
$data.city1 = 'sdf'; // ?this to data of component?
Because you created an new function, the this inside it will be not point to the Vue component, but to the this of the function itself.
You can use an arrow function, or save the reference of the this, then use it later.
created() {
const self = this;
ymaps.init(init);
function init() {
self.city1 = 'sdf';
}
}
Or (better):
created() {
const init = () => {
this.city1 = 'sdf';
}
ymaps.init(init);
}