Pass data to vue component - vue.js

Question

i'm learning Vue.js right now, but i have a little problem on understanding a quite easy task ( maybe my idea of programming is too old ).
i've created a little component with this code.
<template>
<div class="tabSelectorRoot">
<ul>
<li v-for="(element,index) in elements" v-on:click="changeSelected(index)">
<a :class="{ 'selected': activeIndex === index }" :data-value="element.value"> {{ element.text }}</a>
</li>
</ul>
<div class="indicator"></div>
</div>
</template>
<script>
export default {
name: "TabSelectorComponent",
data () {
return {
activeIndex : 0,
elements: [
{ 'text':'Images', 'value': 'immagini','selected':true},
{ 'text':'WallArts', 'value': 'wallart'}
]
}
},
created: function () {
},
methods: {
'changeSelected' : function( index,evt) {
if ( index == this.activeIndex) { return; }
this.activeIndex = index;
document.querySelector('.indicator').style.left= 90 * index +'px';
this.$emit('tabSelector:nameChanged',)
}
}
}
</script>
and this is the root
<template>
<div id="app">
<tab-selector-component></tab-selector-component>
</div>
</template>
<script>
import TabSelectorComponent from "./TabSelectorComponent";
export default {
name: 'app',
components: {TabSelectorComponent},
data () {
return {
msg: 'Welcome to Your Vue.js App'
}
},
'mounted' : function() {
console.log(this)
//EventManager.eventify(this,window.eventManager);
/*this.register('tabSelector:changeValue',function(el){
console.log(el);
});*/
}
}
</script>
All of this renders in something like this
I'd like to reuse the component by varying the number of objects inside the list but i cannot understand how to accomplish this simple task

Answer 1

The basic way to communicate between components in Vue is using properties and events. In your case, what you would want to do is add an elements property to your TabSelectorComponent that is set by the parent.
TabSelectorComponent
export default {
name: "TabSelectorComponent",
props: ["elements"],
data () {
return {
activeIndex : 0
}
},
...
}
In your parent:
<tab-selector-component :elements="elementArray"></tab-selector-component>
This is covered in the documentation here.