如何 Select 按值下拉 dom-重复下拉

Question

我正在尝试在 Polymer 中刷新页面后重新加载下拉设置。下拉列表从 AJAX 调用动态加载，一旦下拉列表被设置，它就会保存在 localStorage 中。

  <select id="customer" on-change="selectCustomer">
    <option value="" selected disabled>Select Customer</option>
    <template is="dom-repeat" items="[[customers]]" as="customer" index-as="index">
      <option value="[[customer]]">[[customer]]</option>
    </template>
  </select>

...

selectCustomer() {
  localStroage.setItem("customerName", this.$.customer.value = index;" 
)

我试过了

setDropdown() {
  // index generated in text matching for loop
  this.$.customer.selectedIndex = index; 
)

和

setDropdown() {
  // customerName generated in text matching for loop
  this.$.customer.value = customerName;
)

Answer 1

我相信更好的方法是将您的下拉值绑定到属性 customer 然后观察 customer 的值并将其保存到本地存储...将其同步到 connectedCallback a demo is always the best way to explain ...

如何 Select 按值下拉 dom-重复下拉

How to Select Dropdown by Value dom-repeat Dropdown

javascript

drop-down-menu

polymer

polymer-2.x

dom-repeat