polygerrit-ui/app/elements/shared/gr-select/gr-select.js

/**
 * @license
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
(function() {
  'use strict';

  /**
   * @appliesMixin Gerrit.FireMixin
   * @extends Polymer.Element
   */
  class GrSelect extends Polymer.mixinBehaviors( [
    Gerrit.FireBehavior,
  ], Polymer.GestureEventListeners(
      Polymer.LegacyElementMixin(
          Polymer.Element))) {
    static get is() { return 'gr-select'; }

    static get properties() {
      return {
        bindValue: {
          type: String,
          notify: true,
          observer: '_updateValue',
        },
      };
    }

    get nativeSelect() {
      return this.$$('select');
    }

    _updateValue() {
      // It's possible to have a value of 0.
      if (this.bindValue !== undefined) {
        // Set for chrome/safari so it happens instantly
        this.nativeSelect.value = this.bindValue;
        // Async needed for firefox to populate value. It was trying to do it
        // before options from a dom-repeat were rendered previously.
        // See https://bugs.chromium.org/p/gerrit/issues/detail?id=7735
        this.async(() => {
          this.nativeSelect.value = this.bindValue;
        }, 1);
      }
    }

    _valueChanged() {
      this.bindValue = this.nativeSelect.value;
    }

    focus() {
      this.nativeSelect.focus();
    }

    /** @override */
    created() {
      super.created();
      this.addEventListener('change',
          () => this._valueChanged());
      this.addEventListener('dom-change',
          () => this._updateValue());
    }

    /** @override */
    ready() {
      super.ready();
      // If not set via the property, set bind-value to the element value.
      if (this.bindValue == undefined && this.nativeSelect.options.length > 0) {
        this.bindValue = this.nativeSelect.value;
      }
    }
  }

  customElements.define(GrSelect.is, GrSelect);
})();