VueJS: Setting data initially based on http response - vuejs2

So I have a template .vue file:
<template>
<div id="app">
<textarea v-model="input" :value="input" #input="update"></textarea>
<div v-html="compiledMarkdown"></div>
</div>
</template>
<script>
var markdown = require('markdown').markdown;
export default {
name: 'app',
data() {
return {
input: '# Some default data'
}
},
mounted: function () {
this.$nextTick(function () {
this.$http.get(window.location.pathname + '/data').then((response) => {
this.input = response.body.markdown;
}) })
},
computed: {
compiledMarkdown: function() {
this.$http.post(window.location.pathname, {
"html": markdown.toHTML(this.input)}).then(function() {
},function() {
});
return markdown.toHTML(this.input);
}
},
methods: {
update: function(e) {
this.input = e.target.value
}
}
}
</script>
In the mounted function I am trying to set input equal to the response of an HTTP request, but when you view this file this.input is still the same as it was initially declared. How can I change this.input inside the compiledMarkdown function to be this.input in the mounted function. What other approaches might I take?

You can not call a async method from a computed property, you can use method or watcher to run asynchronous code, from docs
This is most useful when you want to perform asynchronous or expensive operations in response to changing data.
You have to ran that relevant code when input changes, like following:
var app = new Vue({
el: '#app',
data: {
input: '# Some default data',
markdown : ''
},
methods: {
fetchSchoolData: function (schoolId) {
var url = this.buildApiUrl('/api/school-detail?schoolId=' + schoolId);
this.$http.get(url).then(response => {
this.schoolsListData = response.data;
}).catch(function (error) {
console.log(error);
});
},
},
mounted: function () {
this.$nextTick(function () {
this.$http.get(window.location.pathname + '/data').then((response) => {
this.input = response.body.markdown;
})
})
},
watch: {
// whenever input changes, this function will run
input: function (newInput) {
this.$http.post(window.location.pathname, {
"html": markdown.toHTML(this.input)}).then(function() {
},function() {
this.markdown = markdown.toHTML(this.input);
});
}
},
Have a look at my similar answer here.

Related

vuejs not setting data property from arrow function

I got this weird thing going on here:
I have this data property in vue
data() {
return {
currentLat: 'intial Lat',
currentLong: 'intial Long',
};
},
mounted() {
this.getCurrentLocation();
},
methods: {
getCurrentLocation() {
navigator.geolocation.getCurrentPosition((position) => {
this.currentLat = position.coords.latitude;
this.currentLong = position.coords.longitude;.
console.log(this.currentLat); this prints 41.2111
});
console.log(this.currentLat); this prints 'intial Lat'
},
},
this.currentLat not set in the mount
I dont understand what's happing here! it's so weird!
Here is an example of converting to a promise and using async/await:
async getCurrentLocation() {
const position = await new Promise(resolve => {
navigator.geolocation.getCurrentPosition(position => resolve(position))
});
this.currentLat = position.coords.latitude;
this.currentLong = position.coords.longitude;
console.log(this.currentLat); // shouldn't print initial value
},
Your code is valid, the callback arrow function is asynchronous (it's not executed immediately) and the call of console.log(this.currentLat); is synchronous which makes it to be executed before the callback context, the property is properly if you use it inside the template it will work fine
Set the values in a callback as follows:
<template>
<div id="app">{{ currentLat }} - {{ currentLong }}</div>
</template>
<script>
export default {
data() {
return {
currentLat: "intial Lat",
currentLong: "intial Long",
};
},
mounted() {
this.getCurrentLocation();
},
methods: {
getCurrentLocation() {
navigator.geolocation.getCurrentPosition(this.setCoordinates);
},
setCoordinates(position) {
this.currentLat = position.coords.latitude;
this.currentLong = position.coords.longitude;
},
},
};
</script>

Vue2 create component based on data

I want to create a component based on ajax api response or data which include:
template
data
methods - there may be several methods
Remark: response or data is dynamic and it is not saved in file.
I have tried to generate and return result like :
<script>
Vue.component('test-component14', {
template: '<div><input type="button" v-on:click="changeName" value="Click me 14" /><h1>{{msg}}</h1></div>',
data: function () {
return {
msg: "Test Componet 14 "
}
},
methods: {
changeName: function () {
this.msg = "mouse clicked 14";
},
}
});
</script>
and do compile above code :
axios.get("/api/GetResult")
.then(response => {
comp1 = response.data;
const compiled = Vue.compile(comp1);
Vue.component('result-component', compiled);
})
.catch(error => console.log(error))
I got error on Vue.compile(comp1) -
Templates should only be responsible for mapping the state to the UI. Avoid placing tags with side-effects in your templates, such as
<script>, as they will not be parsed.
Thanks in advance
Your Api should return a JSON with every property required by a Vue component (name, data, template, methods), note that methods needs to be converted into an actual js function (check docs about that)
Vue.config.productionTip = false;
Vue.config.devtools = false;
new Vue({
el: '#app',
data() {
return {
apiComponent: { template: '<div>Loading!</div>' }
};
},
methods: {
loadApiComponent() {
setTimeout(() => {
this.buildApiComponent(JSON.parse('{"name":"test-component14","template":"<div><input type=\\\"button\\\" v-on:click=\\\"changeName\\\" value=\\\"Click me 14\\\" /><h1>{{msg}}</h1></div>","data":{"msg":"Test Componet 14 "},"methods":[{"name":"changeName","body":"{this.msg = \\\"mouse clicked 14\\\";}"}]}'));
}, 2000);
},
buildApiComponent(compObject) {
const {
name,
template,
data,
methods
} = compObject;
const compiledTemplate = Vue.compile(template);
this.apiComponent = {
...compiledTemplate,
name,
data() {
return { ...data
}
},
methods: methods.reduce((c, n) => {
c[n.name] = new Function(n.body);
return c;
}, {})
};
}
},
mounted() {
this.loadApiComponent();
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<component :is="apiComponent" />
</div>

listen to events from dynamic vue components

How would you listen to an event emitted by a dynamically created component instance?
In the example, the top component is added in the DOM, while the second is dynamically created in javascript.
Vue.component("button-counter", {
data: function() {
return {
count: this.initial_count
}
},
props: ['initial_count'],
methods: {
add: function() {
this.count++
this.$emit('myevent', this.count)
}
},
template: '<button v-on:click="add">You clicked me {{ count }} times.</button>'
})
let app = new Vue({
el: "#app",
data() {
return {
initial_count: 10,
}
},
mounted: function() {
let initial_count = this.initial_count
let ButtonCounterComponentClass = Vue.extend({
data: function() {
return {}
},
render(h) {
return h("button-counter", {
props: {
initial_count: initial_count
}
})
}
})
let button_counter_instance = new ButtonCounterComponentClass()
button_counter_instance.$mount()
button_counter_instance.$on('myevent', function(count) {
console.log('listened!')
this.say(count)
})
this.$refs.container.appendChild(button_counter_instance.$el)
},
methods: {
say: function(message) {
alert(message)
}
}
})
<script src="https://cdn.jsdelivr.net/npm/vue#2.6.10/dist/vue.js"></script>
<div id="app">
<button-counter initial_count=20 v-on:myevent="say"></button-counter>
<div ref='container'></div>
</div>
If I've understood what you want then you just need to listen for the event on the inner component and pass it on.
I've used arrow functions in a couple of places to avoid problems with this bindings. Otherwise I've tried to leave your code unchanged as much as possible. Changes marked with ****.
Vue.component("button-counter", {
data: function() {
return {
count: this.initial_count
}
},
props: ['initial_count'],
methods: {
add: function() {
this.count++
this.$emit('myevent', this.count)
}
},
template: '<button v-on:click="add">You clicked me {{ count }} times.</button>'
})
let app = new Vue({
el: "#app",
data() {
return {
initial_count: 10,
}
},
mounted: function() {
let initial_count = this.initial_count
let ButtonCounterComponentClass = Vue.extend({
data: function() {
return {}
},
render(h) {
return h("button-counter", {
props: {
initial_count: initial_count
},
// **** Added this ****
on: {
myevent: count => {
this.$emit('myevent', count);
}
}
// ****
})
}
})
let button_counter_instance = new ButtonCounterComponentClass()
button_counter_instance.$mount()
// **** Changed the next line ****
button_counter_instance.$on('myevent', count => {
console.log('listened!')
this.say(count)
})
this.$refs.container.appendChild(button_counter_instance.$el)
},
methods: {
say: function(message) {
alert(message)
}
}
})
<script src="https://cdn.jsdelivr.net/npm/vue#2.6.10/dist/vue.js"></script>
<div id="app">
<button-counter initial_count=20 v-on:myevent="say"></button-counter>
<div ref='container'></div>
</div>
It's important to understand that button_counter_instance is not an instance of your button-counter component. You've wrapped it in another component, albeit a component that doesn't add any extra DOM nodes. So listening on the wrapper component is not the same as listening on button-counter.
Docs for what you can pass to h: https://v2.vuejs.org/v2/guide/render-function.html#The-Data-Object-In-Depth

How to set a value inside a variable on data() using a function?

I'm creating a Vue.js component inside a Laravel App.
After I catch the response with an axios request, I can't put a value inside a variable on method data()
Here is the code:
app.js
require('./bootstrap')
window.Vue = require('vue')
Vue.component('card', require('./components/card.vue'))
let app = new Vue({
el: '#app'
})
card.vue
<script>
module.exports = {
props: [
'name'
],
data: function() {
return {
projects: [],
}
},
mounted() {
this.getProjects() // NOT WORK?
},
methods: {
getProjects: function() {
axios.get('/api/v1/getProjects').then(function (response) {
console.log(response.data)
this.projects = response.data // NOT WORK
}).catch(function (error) {
console.log(error)
}).then(function () {
})
},
}
}
</script>
It's because of using this in response callback. You should use an arrow function (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions) or save the context in separate variable.
Try to add .bind(this) or replace function with =>:
getProjects: function() {
axios.get('/api/v1/getProjects').then((response) => {
console.log(response.data)
this.projects = response.data // NOT WORK
}).catch((error) => {
console.log(error)
}).then(function () {
})
},

How to destroy vuejs component from outside of component

I have created one of component in vuejs something like this
var tree_data = Vue.extend({
template: '#tree_data_template',
props: [
'groupmodal',
'search-name',
'tree-id'
], // props in single quotes
data: function () {
return {
shared: d2d.store
};
}
});
And use this component in another template like this.
var template_data = Vue.extend({
template: '#template_data',
created: function () {
var self = this;
self.shared.setCurrentRoute('templates');
},
components: {
'tree-data': tree_data
},
data: function () {
return {
id: this.$route.params.id,
shared: d2d.store,
};
},
methods: {
destroyComponent: function () {
//Need to code for destroy tree-data component
}
}
});
Blade file code
<tree-data
groupmodal="false"
search-name="user_search"
tree-id="user_tree"
>
</tree-data>
So finally how can i destroy my "tree-data" component through the "destroyComponent()" method
As cobaltway said you can use v-if
Setting v-if initially to false will render(generate) the component.
Then in your method setting v-if to true will destroy the component.
html
<div id="template_data">
<tree-data v-if="destroyComponent"></tree-data>
</div>
script
var template_data = Vue.extend({
template: '#template_data',
created: function () {
var self = this;
self.shared.setCurrentRoute('templates');
},
components: {
'tree-data': tree_data
},
data: function () {
return {
id: this.$route.params.id,
shared: d2d.store,
destroyComponent:true
};
},
methods: {
destroyComponent: function () {
//Need to code for destroy tree-data component
this.destroyComponent = false;
}
}
});
Here is the fiddle