How one can do custom two-way filter for model, updating on the fly in Vue.js.
The following code example from docs works on input blur. But I need it work on keypress.
Vue.filter('currencyDisplay', {
read: function(val) {
return '$'+val.toFixed(2)
},
write: function(val, oldVal) {
var number = +val.replace(/[^\d.]/g, '')
return isNaN(number) ? 0 : parseFloat(number.toFixed(2))
}
})
Many thanks in advance for any help!
You can apply a filter to a Vue data property by creating a computed property with a get and set method that fire the read and write methods of the filter, respectively:
data() {
return {
foo: 0,
}
},
computed: {
filteredFoo: {
get() {
return Vue.filter('currencyDisplay').read(this.foo);
},
set(value) {
this.foo = Vue.filter('currencyDisplay').write(value);
}
}
}
Here's a working fiddle.
Related
I'm on Vue 3. I have an onclick method which is supposed to modify the value of my props which is a boolean, I have tried several ways, I manage to enter the computed method, but the value of my props does not change
I register my data
data() {
return {
showConsommationWindow: false
}
}
then I tried 3 ways to change the value but none of them worked.
The first :
<submit-button v-on:click="showConsommationWindow = true" />
the 2nd : (alert is executed but the data value don't change)
<submit-button v-on:click="showConsommation(true)"/>
methods: {
showConsommation(boolValue){
alert('false')
this.showConsommationWindow = boolValue;
}
}
The last :
<submit-button v-on:click="showConsommation"/>
methods: {
showConsommation(){
if (!this.showConsommationWindow) {
alert('false')
this.showConsommationWindow = true;
return
}
this.showConsommationWindow = false;
}
},
I really don't understand why my data can't mutate, thanks for your help.
If value comes from a props, it means the parent distributes a boolean to the component. So if you want to change the boolean value, you should probably do:
// in parent
<Component :booleanValue="myBoolean" #changeBooleanValueEvent="changeMyBoolean" />
...
data() {
return {
myBoolean: true
}
}
methods: {
changeMyBoolean(value) {
this.myBoolean = value
}
}
// in component
props: {
booleanValue: {
...
}
}
methods: {
showConsommation() {
this.$emit('changeBooleanValueEvent', false)
}
}
In a SFC I have
filters: {
localizedData: function () {
return new Date(value).toLocaleString();
}
}
and
computed: {
todos() {
return _.map(this.raw_todos, item => {
return {
...item.node,
localizedData: this.$filters.localizedData(item.node.giorno)
}
});
}
},
The part not working is
this.$filters
because it's undefined. this is the Vue instance, but it has not the $filters... also I tried
this.localizeData(..)
but .localizeData is not a function
What am I doing wrong and why?
Just like #Eric Guan said, filter is in this.$options.filters
You can refer to this https://stackblitz.com/edit/js-vue-filter-in-vm-instance
i'm trying to watch an array declarated in data method (the 'validated' variable). I already have a watcher to an input (legal_name) and it works correctly but the array watcher doesnt give any response. Any idea?
export default {
data() {
return {
legal_name : '',
validated: [],
errors: []
}
},
watch: {
validated() {
console.log('modified')
},
legal_name(value) {
this.eventName();
this.legal_name = value;
this.checkLength(value, 3);
}
},
methods: {
checkLength(value, lengthRequired) {
if(value.length < lengthRequired) {
this.errors[name] = `Debes ingresar al menos ${lengthRequired} caracteres`;
this.validated[name] = false;
return false;
}
this.errors[name] = '';
this.validated[name] = true;
return true;
},
eventName() {
name = event.target.name;
}
}
}
You need to call Vue.set() for arrays, and NOT use indexing such as
foo[3]= 'bar'
Vue DOES recognize some operations, such as splice and push, however.
Read more about it here: https://vuejs.org/2016/02/06/common-gotchas/ and here: https://v2.vuejs.org/v2/guide/list.html#Array-Change-Detection
So for your code, and using the Vue handy helper method $set:
this.validated.$set(name, true);
Why...
Javascript does not offer a hook (overload) for the array index operator ([]), so Vue has no way of intercepting it. This is a limitation of Javascript, not Vue. Here's more on that: How would you overload the [] operator in javascript
I have a simple form in a component :
<form v-on:submit.prevent="submitSearch">
<input v-model="objId" #paste="submitSearch">
<button>Submit</button>
</form>
and
var searchForm = {
methods : {
submitSearch() {
store.dispatch('submitSearch')
}
},
computed : {
objId: {
get () {
return ...
},
set (id) {
store.commit('objId', id)
}
}
},
...
};
It works well when typing and submitting, however when pasting a value submitSearch is called just before objId is updated so it doesn't. Is there a consise and vue-friendly way to handle this?
One way you could do it is have a local variable isPaste and set it to true, when the paste event is triggered. Then also register an input event which will trigger after the paste event and check if isPaste is true. If it is, then submit and set isPaste to false again.
<input v-model="objId" #paste="paste" #input="input">
data(): {
return {
isPaste: false
}
},
methods: {
paste() {
this.isPaste = true;
},
input() {
if (this.isPaste) {
store.dispatch('submitSearch');
isPaste = false;
}
}
}
Solved it using nextTick() :
submitSearch() {
Vue.nextTick().then(function () {
store.dispatch('submitSearch')
})
}
Not sure if it's the recommended way but it works well and avoid extra variables.
In my reducer, suppose originally I have this state:
{
"loading": false,
"data": {
"-L1LwSwW97KkwdSnYvsc": {
"likeCount": 10,
"liked": false, // I want to update this property
"commentCount": 5
},
"-L1EY2_fqzn7sM1Mbf_F": {
"likeCount": 8,
"liked": true,
"commentCount": 22
}
}
}
Now, I want to update liked property inside -L1LwSwW97KkwdSnYvsc object, which is inside data object and make it true. This is what I've been trying, but apparently, it's wrong, because after I've updated the state, the componentWillReceiveProps function inside a component that listens to the state change does not get triggered:
var { data } = state;
data['-L1LwSwW97KkwdSnYvsc'].liked = !data['-L1LwSwW97KkwdSnYvsc'].liked;
return { ...state, data };
Could you please specify why it's wrong and how I should change it to make it work?
You're mutating state! When you destructure:
var { data } = state;
It's the same as:
var data = state.data;
So when you do:
data[…].liked = !data[…].liked
You're still modifying state.data which is in turn mutating state. That's never good - use some nested spread syntax:
return {
...state,
data: {
...state.data,
'-L1LwSwW97KkwdSnYvsc': {
...state.data['-L1LwSwW97KkwdSnYvsc'],
liked: !state.data['-L1LwSwW97KkwdSnYvsc'].liked
}
}
};
Using spread operator is good until you start working with deeply nested state and/or arrays(remember spread operator does a shallow copy only).
I would rather recommend you starting working with immutability-helper instead. It is a React recommendation and it will let your code more readable and bug free.
Example:
import update from "immutability-helper";
(...)
const toggleLike = !state.data["-L1LwSwW97KkwdSnYvsc"].liked
return update(state, {
data: {
"-L1LwSwW97KkwdSnYvsc": {
like: {
$set: toggleLike
}
}
}
})