SOURCE

var Main = {
    data() {
      return {
        active: 0
      };
    },

    methods: {
      next() {
        if (this.active++ > 2) this.active = 0;
      }
    }
  }
var Ctor = Vue.extend(Main)
new Ctor().$mount('#app')

<script src="//unpkg.com/vue/dist/vue.js"></script>
<script src="//unpkg.com/element-ui@2.3.8/lib/index.js"></script>
<div id="app">
<el-steps :active="active" finish-status="success">
  <el-step title="步骤 1"></el-step>
  <el-step title="步骤 2"></el-step>
  <el-step title="步骤 3"></el-step>
</el-steps>

<el-button style="margin-top: 12px;" @click="next">下一步</el-button>
</div>

@import url("//unpkg.com/element-ui@2.3.8/lib/theme-chalk/index.css");