set value of input programatically doesn't refresh component DOM - vue.js

I have an input which is bidden to property message. I have a set button , which I use for changing of input value programmatically. When the button is pressed, value of input is correctly changed to 'xxxx'. when I press clean button after that , the input is correctly cleaned but when I repeat pressing set and clean again the input does not get cleared anymore.
Working example is here:
https://codepen.io/dan-ouek/pen/rNBjxRO
<div class="container">
<div id='root' class="box">
<input ref="templateFilter" type='text' id='input' v-model='message'>
{{ message }}
<button #click="set">set</button>
<button #click="clean">clean</button>
</div>
</div>
new Vue({
el: '#root',
data: {
message: 'Hello Vue'
},
methods: {
set: function () {
let element = this.$refs.templateFilter
Vue.set(element, 'value', 'xxxx')
}, clean: function () {
this.message = ""
}
}})
Questions:
1) Is it possible to change input programmatically without working with bidden property value? Something like direct DOM manipulation:
let element = document.getElementsByClassName("templateFilter")[0]
element.value = 'xxxxx'
but with proper component refresh?
2) Why is the {{ message }} not refreshed after calling set method?

Why is the message not refreshed after calling set method?
When you type something on your input the message data gets updated via an event handler BUT when you set it programmatically the event handler is NOT triggered and that's why message was not getting updated / refreshed....
Solution :
a short solution to your issue would be just to mutate the message value this.message = "xxxx" but if you insist on making that programmatically you have to trigger the input event :
set: function() {
let element = this.$refs.templateFilter
Vue.set(element, 'value', 'xxxx')
element.dispatchEvent(new Event('input'))
}
Here is a Demo : codepen

Related

In Vue, how to get the content of a textarea?

I want to keep the value of a variable identical with the content of a textarea.
I don't want to use v-bind or v-model, because I have already bound the textarea with another value.
This is a notebook app, and the textarea is used to display the content of a note, so it has been bound using v-bind with a note object, like
<textarea cols="30" rows="3" v-bind:value="note"></textarea>
Now, I want to add the "edit note" functionality. So when the content of the textarea changes, I want to store its value into a variable, and when the "submit" button is clicked, I pass the value of the variable, which contains the new content of the note, to backend to update the note.
My question is, how to store the textarea's content into the variable after each time the content changes?
I think I cannot use v-model because this way the note will be changed right after the content of the textarea is modified (though not sent to backend), but this is not what I want. What I want is the note to be changed only after the "submit" button is clicked. Thus, I cannot use v-model
Should I use v-on:change? If so, how to get the content of the textarea?
Like,
<textarea v-on:change="updateTheVariable(I need to get the content of the textarea here)"> ... </textarea>
methods: {
updateTheVariable(content of the textarea) {
this.variable = content of the textarea
}
}
Thanks
I'm assuming this thing only shows up when you click some kind of edit button which is why you don't want to alter note so try something like this instead
<button type="button" v-if="!editMode" #click="editNote">Edit</button>
<form v-if="editMode" #submit="handleSubmit">
<fieldset :disabled="saving">
<textarea v-model="editingNote"></textarea>
<button type="submit">Edit</button>
</fieldset>
</form>
export default {
data: () => ({
note: 'whatever', // maybe it's a prop, maybe assigned later, doesn't matter
editMode: false,
editingNote: null, // this will be used to bind the edited value
saving: false
}),
methods: {
editNote () {
this.editingNote = this.note
this.editMode = true
this.saving = false
},
async handleSubmit () {
this.saving = true // disables form inputs and buttons
await axios.post('/notes/update', { note: this.editingNote}) // just an example
this.note = this.editingNote // or maybe use data from the response ¯\_(ツ)_/¯
// or if it's a prop, this.$emit('updated', this.editingNote)
this.editMode = false
}
}
}
As #Phil indicated in a deleted post, the right way to do it is
<textarea #input="updateTheVariable($event.target.value)"></textarea>
.
.
.
methods:{
updateTheVariable(value){
this.variable = value
}
}

bind switch and form input in vuejs

I'm looking for the VueJS best practice for synchronizing between the input element and the switch element in the following piece of code:
<div class="filter panel">
<div class="field_title">Device</div>
<el-switch v-model="switches.device_switch" name="device"></el-switch>
<b-form-input v-model="device" placeholder="Device"></b-form-input>
</div>
If the input field contains any text I would like to set the v-model="switches.device_switch" to true.
How can I achieve this?
Set a watcher for the device property bound to the input. In the watcher, you can set the value of switches.device_switch based on the length of the device string:
watch: {
device: function(value) {
this.switches.device_switch = value.length !== 0;
}
}

dynamic change doesn't work on vuejs input

i'm working on a vue file and have a form :
<div class="input-group">
<span class="input-group-addon">Montant</span>
<input type="number" class="form-control" v-model="amount" v-bind:value="pattern['value']"]>
</div>
my tab pattern is loaded like that :
var request = $.ajax({
url: '{{ path ('home') }}promos/pattern/'+value,
})
request.success(function(data){
if(data['pattern']==='yes'){
this.pattern=data[0];
alert(this.pattern['value']);
}
})
and my instance :
var instance = new Vue({
el: "#General",
data: {
[...]
pattern: []
}
and the request is made evertyime i do 'action a'. I have the right alert with the value i want everytime i do 'action a' but the input stays at 0 and won't dynamically change.
Something is wrong with your code. Firstly, let's look at your ajax request:
request.success(function(data){
if(data['pattern']==='yes'){
this.pattern=data[0];
alert(this.pattern['value']);
}
})
What is the form of your data response? Because you are checking something with data['pattern'], and then you are trying to associate to this.pattern something that you call data[0]
Then, as stated in #thanksd answer, you are referencing a wrong this in your ajax callback, you need to create a self variable:
var self = this
var request = $.ajax({
url: '{{ path ('home') }}promos/pattern/'+value,
})
request.success(function(data){
if(data['pattern']==='yes'){
self.pattern=data[0];
alert(this.pattern['value']);
}
})
Finally, you write:
<input type="number" class="form-control" v-model="amount" v-bind:value="pattern['value']"]>
So there are a few mistakes here. Firstly, you have a ] at the end of the line that has nothing to do here.
Secondly, you are using v-bind:value, this is not something that is going to be responsive. If you want this input to be responsive, you should use v-model and set the value of amount when you want to change the input value.
Hope this helps
Three things:
The this in your success handler is not referencing the Vue instance. You need to set a reference outside the scope of the handler and use that instead.
You can't chain a success callback to jQuery's ajax method in the first place. It's defined as a property in the parameter object passed to the call. (Maybe you copied code over wrong?)
You need to get rid of v-model="amount" if you want the input's value to reflect the value bound by v-bind:value="pattern"
Your code should look like this:
let self = this; // set a reference to the Vue instance outside the callback scope
var request = $.ajax({
url: '{{ path ('home') }}promos/pattern/'+value,
success: function(data) { // success handler should go in the parameter object
if (data['pattern']==='yes') {
self.pattern=data[0];
alert(this.pattern['value']);
}
}
})

vue.js method can't access variable from data object with multiple rows

I am currently learning vue.js and having trouble accessing data in the methods.
data is loaded and set as a global variable (for now, this will probably change but not part of the problem now i think)
through ajax call this data is received:
data":[{"itemId":"58646f066803fa62388b4573","color":"#ffb878","name":"test1","startDate":"04/24/2017","work":"9.25"},{"itemId":"58646f066803fa62388b4572","color":"#ffb878","name":"test2","startDate":"04/24/2017","work":"4.25"},{"itemId":"58646f066803fa62388b4571","color":"#a4bdfc","name":"test3","startDate":"05/01/2017","work":"24.00"}]
which is set as a global (variable data is set outside of the functions) with:
...success: function (jsonObj)
{
data['item'] = jsonObj.data
....
now for the vue part:
var app = new Vue({
el:'#canvas',
data: {
items: data['item']
},
methods: {
moveItem: function(){
console.log("new date: "+this.startDate);
}
}
})
the html:
<div v-for="row in items" class="entirerow" v-bind:id="'row'+row.itemId">
<div class="itemrow">{{ row.name }}</div>
<div class="itemrow"><input type="text" v-model="row.startDate" #change="moveItem"></div>
<div class="itemrowlast">{{ row.work }}</div>
</div>
this nicely shows 3 rows with the correct data in each row. So far so good. But now if I change something in the input value the method moveItem is triggered but states "new date: undefined" in the console.log
I've tried console.log("new date: "+this.items.startDate) as well but no cigar and then it would seem the method wouldn't know which row is handled.
How can I access the correct data in the method, so from a certain row in the loop?
Thanks!
You refer to data object in method (this.startDate) not to item
moveItem: function(){
console.log("new date: "+this.startDate);
}
You can change your code like this
template
#change="moveItem(row)"
script
moveItem: function(row){
console.log("new date: " + row.startDate);
}

Set focus for paper-input via radio button

In Polymer (1.0), how can I set the focus of the iron-input when (as example) radiobutton 'radio1' is selected.
<div>
<div>Title:</div>
<paper-radio-group>
<paper-radio-button name="radio1">Radio1Label</paper-radio-button>
<paper-radio-button name="radio2">Radio2Label</paper-radio-button>
</paper-radio-group>
<paper-input-container>
<input is="iron-input">
</paper-input-container>
</div>
You will need to bind a click event to radio1:
<paper-radio-button name="radio1" on-click="_setInputFocus">Radio1Label</paper-radio-button>
Then define the function _setInputFocus so that it selects the input and sets the focus to it:
<script>
Polymer({
is: 'the-name-of-your-element',
_setInputFocus: function () {
this.$$("input").focus();
}
});
</script>
EDIT: Now we want the input disabled until the user selects the radio button. So we give the iron-input the disabled attribute:
<paper-input-container>
<input is="iron-input" disabled>
</paper-input-container>
Then we change our JavaScript function so that we remove the disabled attribute and sets the input focus:
<script>
Polymer({
is: "focus-test",
_setInputFocus: function () {
var inputElement = this.$$("input"); // grab the element
inputElement.toggleAttribute("disabled", false); // remove the disabled attribute
inputElement.focus(); // set the focus to this input
}
});
</script>
You could also use the <paper-input> instead of the <paper-input-container> element and then use
setTimeout(function() {
this.$.tabname.inputElement.focus()
}.bind(this), 200);
in your function. (The set timeout is sometimes necessary because if another element had focus and is about to close (e.g. an iron-dropdown) then you would have to wait for this to finish before giving focus to the input)