title: how to control bootstrapvue b-table trClass by boolean
body: <p>I am using a b-table from BootstrapVue. However Each row  have a button and
  when i click the button i want to change the row background to another color,
  i find tbody-tr-class can control but that can not allow the button control</p>
  <blockquote>
  <p>The Changes and noChange is scss name</p>
  </blockquote>
  <pre><code>&lt;b-table :sticky-header=&quot;true&quot;
               responsive
               :fields=&quot;fields&quot; :items=&quot;items&quot; :no-border-collapse=&quot;true&quot;
      :tbody-tr-class = &quot;this.changeColor!=false ? 'Changes' : 'noChange'&quot;
      &gt;
        &lt;!--      ref=&quot;selectable&quot;--&gt;
        &lt;!--      select-mode=&quot;single&quot;--&gt;
        &lt;!--      selectable--&gt;
        &lt;template v-slot:cell(\r)=&quot;row&quot;&gt;
          &lt;b-dropdown toggle-class=&quot;dropdown&quot; size=&quot;lg&quot; variant=&quot;link&quot; text=&quot;...&quot; no-caret&gt;
            &lt;b-dropdown-item @click=&quot;onClickButton1(row.item)&quot;&gt;buttonName&lt;/b-dropdown-item&gt;
          &lt;/b-dropdown&gt;
        &lt;/template&gt;
      &lt;/b-table&gt;   
  </code></pre>
  <p>methods</p>
  <pre><code>data(){
      return{
         changeColor:false;
      }
  }
  methods:{
      onClickButton1(item){
          this.changeColor = true;
          console.log(item)
      }
  }
  </code></pre>