title: Change dynamic nested json values
body: <p>this is my Json :</p>
  <pre><code>{
      &quot;name&quot;: &quot;table&quot;,
      raw_material: {
          &quot;iron&quot;: 2,
          &quot;wood&quot;: 1,
          &quot;glue&quot;: 1
      }
  }
  </code></pre>
  <p>Sometimes, it is different:</p>
  <pre><code>{
      &quot;name&quot;: &quot;table&quot;,
      raw_material: {
          &quot;iron&quot;: 2,
          &quot;plastic&quot;: 1,
          &quot;glue&quot;: 1,
          &quot;water&quot;:4
      }
  }
  </code></pre>
  <p>I need to elaborate a form who will allow me to update any raw_material value, no matter the amount of key value  .
  This is what I have :</p>
  <pre><code>&lt;li v-for=&quot;(value, key, index) in this.item.raw_material&quot; :key=&quot;index&quot;&gt;
      {{ key }} : {{ value }} : {{ index }}
      &lt;b-form-input v-model=&quot;value&quot;&gt;&lt;/b-form-input&gt;
  &lt;/li&gt;
  </code></pre>
  <p>The loop is ok .
  Unfortunatly, the value is not changed (2 ways binding) when I type something in the input field .</p>
  <p>Any idea ?</p>