已禁用提交按钮,但有效的表单数据将不启用它(vee validate)

我正试图禁用表单的提交按钮,直到为每个控件输入有效数据。

在为每个字段输入正确的数据后,“提交”按钮将保持禁用状态。

标记:

<div id="app">
  <form action='#' method='POST'>

    <div class="columns">

      <div class="column">
        <div class="field">
          <div class="control">
            <label class="label">Last Name</label>
            <input v-validate="'required'" :class="{'input': true, 'is-danger': errors.has('lastname') }" class="input" name="lastname" type="text">
            <span v-show="errors.has('lastname')" class="help is-danger">{{ errors.first('lastname') }}</span>
          </div>
        </div>
      </div>

      <div class="column">
        <div class="field">
          <div class="control">
            <label class="label">Desk Number</label>
            <input v-validate="'required'" :class="{'input': true, 'is-danger': errors.has('desknum') }" class="input" name="desknum" type="text">
            <span v-show="errors.has('desknum')" class="help is-danger">{{ errors.first('desknum') }}</span>
          </div>
        </div>
      </div>
    </div>

    <button :disabled='!isComplete' class="button is-link" name='submit_data' value='go'>Submit</button>
  </form>
</div>

<script src="https://cdnjs.cloudflare.com/ajax/libs/bulma/0.7.1/css/bulma.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.16/vue.min.js">
<script src="https://cdnjs.cloudflare.com/ajax/libs/vee-validate/2.0.9/vee-validate.min.js">
<script>

            Vue.use(VeeValidate);
            new Vue({
              el: "#app",
              template: '#app',
              data() {
                return {
                  p_pat_name_first: null,
                  p_pat_name_last: null,
                  p_pat_date_birth: null,
                  p_pat_gender: null,
                  p_pat_twin: null,
                  p_emory_id: null,
                  p_mother_name_first: null,
                  p_mother_name_last: null,
                  p_parent_phone_primary: null,
                };
              },
              computed: {
                isComplete() {
                  return
                  this.p_pat_name_first &&
                    this.p_pat_name_last &&
                    this.p_pat_date_birth &&
                    this.p_pat_gender &&
                    this.p_pat_twin &&
                    this.p_mother_name_first &&
                    this.p_mother_name_last &&
                    this.p_parent_phone_primary;
                }
              }
            });

</script>

Fiddle

当表单完整且有效时,如果不允许提交按钮自行启用,我会怎么做?