"You are binding v-model directly to a v-for iteration alias"
vue.jsvue.js Problem Overview
Just run into this error I hadn't encountered before: "You are binding v-model directly to a v-for iteration alias. This will not be able to modify the v-for source array because writing to the alias is like modifying a function local variable. Consider using an array of objects and use v-model on an object property instead." I am a little puzzled, as I don't appear to be doing anythong wrong. The only difference from other v-for loops I've used before is that this one is a little simpler, in that it's simply looping through an array of strings, rather than objects:
<tr v-for="(run, index) in this.settings.runs">
<td>
<text-field :name="'run'+index" v-model="run"/>
</td>
<td>
<button @click.prevent="removeRun(index)">X</button>
</td>
</tr>
The error message would seem to suggest that I need to actually make things a little more complicated, and use objects instead of simple strings, which somehow doesn't seem right to me. Am I missing something?
vue.js Solutions
Solution 1 - vue.js
Since you're using v-model
, you expect to be able to update the run
value from the input field (text-field
is a component based on text input field, I assume).
The message is telling you that you can't directly modify a v-for
alias (which run
is). Instead you can use index
to refer to the desired element. You would similarly use index
in removeRun
.
new Vue({
el: '#app',
data: {
settings: {
runs: [1, 2, 3]
}
},
methods: {
removeRun: function(i) {
console.log("Remove", i);
this.settings.runs.splice(i,1);
}
}
});
<script src="//cdnjs.cloudflare.com/ajax/libs/vue/2.5.18/vue.js"></script>
<table id="app">
<tr v-for="(run, index) in settings.runs">
<td>
<input type="text" :name="'run'+index" v-model="settings.runs[index]" />
</td>
<td>
<button @click.prevent="removeRun(index)">X</button>
</td>
<td>{{run}}</td>
</tr>
</table>