Edit in JSFiddle

var app = new Vue({
  el: '#app',
  data: {
    chartData: [
      {sales: 100},
      {sales: 200},
      {sales: 300}
    ]
  },
});

<div id="app">
  <wj-flex-chart class="chart" :items-source="chartData" binding-x="country">
    <wj-flex-chart-series name="Sales" binding="sales"></wj-flex-chart-series>
  </wj-flex-chart>
</div>