187 lines
		
	
	
		
			5.6 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			187 lines
		
	
	
		
			5.6 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
import Keyboard from '../modules/keyboard';
 | 
						|
import DropdownIcon from '../assets/icons/dropdown.svg';
 | 
						|
 | 
						|
let optionsCounter = 0;
 | 
						|
 | 
						|
function toggleAriaAttribute(element, attribute) {
 | 
						|
  element.setAttribute(attribute, !(element.getAttribute(attribute) === 'true'));
 | 
						|
}
 | 
						|
 | 
						|
class Picker {
 | 
						|
  constructor(select) {
 | 
						|
    this.select = select;
 | 
						|
    this.container = document.createElement('span');
 | 
						|
    this.buildPicker();
 | 
						|
    this.select.style.display = 'none';
 | 
						|
    this.select.parentNode.insertBefore(this.container, this.select);
 | 
						|
 | 
						|
    this.label.addEventListener('mousedown', () => {
 | 
						|
      this.togglePicker();
 | 
						|
    });
 | 
						|
    this.label.addEventListener('keydown', (event) => {
 | 
						|
      switch(event.keyCode) {
 | 
						|
        // Allows the "Enter" key to open the picker
 | 
						|
        case Keyboard.keys.ENTER:
 | 
						|
          this.togglePicker();
 | 
						|
          break;
 | 
						|
 | 
						|
        // Allows the "Escape" key to close the picker
 | 
						|
        case Keyboard.keys.ESCAPE:
 | 
						|
          this.escape();
 | 
						|
          event.preventDefault();
 | 
						|
          break;
 | 
						|
        default:
 | 
						|
      }
 | 
						|
    });
 | 
						|
    this.select.addEventListener('change', this.update.bind(this));
 | 
						|
  }
 | 
						|
 | 
						|
  togglePicker() {
 | 
						|
    this.container.classList.toggle('ql-expanded');
 | 
						|
    // Toggle aria-expanded and aria-hidden to make the picker accessible
 | 
						|
    toggleAriaAttribute(this.label, 'aria-expanded');
 | 
						|
    toggleAriaAttribute(this.options, 'aria-hidden');
 | 
						|
  }
 | 
						|
 | 
						|
  buildItem(option) {
 | 
						|
    let item = document.createElement('span');
 | 
						|
    item.tabIndex = '0';
 | 
						|
    item.setAttribute('role', 'button');
 | 
						|
 | 
						|
    item.classList.add('ql-picker-item');
 | 
						|
    if (option.hasAttribute('value')) {
 | 
						|
      item.setAttribute('data-value', option.getAttribute('value'));
 | 
						|
    }
 | 
						|
    if (option.textContent) {
 | 
						|
      item.setAttribute('data-label', option.textContent);
 | 
						|
    }
 | 
						|
    item.addEventListener('click', () => {
 | 
						|
      this.selectItem(item, true);
 | 
						|
    });
 | 
						|
    item.addEventListener('keydown', (event) => {
 | 
						|
      switch(event.keyCode) {
 | 
						|
        // Allows the "Enter" key to select an item
 | 
						|
        case Keyboard.keys.ENTER:
 | 
						|
          this.selectItem(item, true);
 | 
						|
          event.preventDefault();
 | 
						|
          break;
 | 
						|
 | 
						|
        // Allows the "Escape" key to close the picker
 | 
						|
        case Keyboard.keys.ESCAPE:
 | 
						|
          this.escape();
 | 
						|
          event.preventDefault();
 | 
						|
          break;
 | 
						|
        default:
 | 
						|
      }
 | 
						|
    });
 | 
						|
 | 
						|
    return item;
 | 
						|
  }
 | 
						|
 | 
						|
  buildLabel() {
 | 
						|
    let label = document.createElement('span');
 | 
						|
    label.classList.add('ql-picker-label');
 | 
						|
    label.innerHTML = DropdownIcon;
 | 
						|
    label.tabIndex = '0';
 | 
						|
    label.setAttribute('role', 'button');
 | 
						|
    label.setAttribute('aria-expanded', 'false');
 | 
						|
    this.container.appendChild(label);
 | 
						|
    return label;
 | 
						|
  }
 | 
						|
 | 
						|
  buildOptions() {
 | 
						|
    let options = document.createElement('span');
 | 
						|
    options.classList.add('ql-picker-options');
 | 
						|
 | 
						|
    // Don't want screen readers to read this until options are visible
 | 
						|
    options.setAttribute('aria-hidden', 'true');
 | 
						|
    options.tabIndex = '-1';
 | 
						|
 | 
						|
    // Need a unique id for aria-controls
 | 
						|
    options.id = `ql-picker-options-${optionsCounter}`;
 | 
						|
    optionsCounter += 1;
 | 
						|
    this.label.setAttribute('aria-controls', options.id);
 | 
						|
 | 
						|
    this.options = options;
 | 
						|
 | 
						|
    [].slice.call(this.select.options).forEach((option) => {
 | 
						|
      let item = this.buildItem(option);
 | 
						|
      options.appendChild(item);
 | 
						|
      if (option.selected === true) {
 | 
						|
        this.selectItem(item);
 | 
						|
      }
 | 
						|
    });
 | 
						|
    this.container.appendChild(options);
 | 
						|
  }
 | 
						|
 | 
						|
  buildPicker() {
 | 
						|
    [].slice.call(this.select.attributes).forEach((item) => {
 | 
						|
      this.container.setAttribute(item.name, item.value);
 | 
						|
    });
 | 
						|
    this.container.classList.add('ql-picker');
 | 
						|
    this.label = this.buildLabel();
 | 
						|
    this.buildOptions();
 | 
						|
  }
 | 
						|
 | 
						|
  escape() {
 | 
						|
    // Close menu and return focus to trigger label
 | 
						|
    this.close();
 | 
						|
    // Need setTimeout for accessibility to ensure that the browser executes
 | 
						|
    // focus on the next process thread and after any DOM content changes
 | 
						|
    setTimeout(() => this.label.focus(), 1);
 | 
						|
  }
 | 
						|
 | 
						|
  close() {
 | 
						|
    this.container.classList.remove('ql-expanded');
 | 
						|
    this.label.setAttribute('aria-expanded', 'false');
 | 
						|
    this.options.setAttribute('aria-hidden', 'true');
 | 
						|
  }
 | 
						|
 | 
						|
  selectItem(item, trigger = false) {
 | 
						|
    let selected = this.container.querySelector('.ql-selected');
 | 
						|
    if (item === selected) return;
 | 
						|
    if (selected != null) {
 | 
						|
      selected.classList.remove('ql-selected');
 | 
						|
    }
 | 
						|
    if (item == null) return;
 | 
						|
    item.classList.add('ql-selected');
 | 
						|
    this.select.selectedIndex = [].indexOf.call(item.parentNode.children, item);
 | 
						|
    if (item.hasAttribute('data-value')) {
 | 
						|
      this.label.setAttribute('data-value', item.getAttribute('data-value'));
 | 
						|
    } else {
 | 
						|
      this.label.removeAttribute('data-value');
 | 
						|
    }
 | 
						|
    if (item.hasAttribute('data-label')) {
 | 
						|
      this.label.setAttribute('data-label', item.getAttribute('data-label'));
 | 
						|
    } else {
 | 
						|
      this.label.removeAttribute('data-label');
 | 
						|
    }
 | 
						|
    if (trigger) {
 | 
						|
      if (typeof Event === 'function') {
 | 
						|
        this.select.dispatchEvent(new Event('change'));
 | 
						|
      } else if (typeof Event === 'object') {     // IE11
 | 
						|
        let event = document.createEvent('Event');
 | 
						|
        event.initEvent('change', true, true);
 | 
						|
        this.select.dispatchEvent(event);
 | 
						|
      }
 | 
						|
      this.close();
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  update() {
 | 
						|
    let option;
 | 
						|
    if (this.select.selectedIndex > -1) {
 | 
						|
      let item = this.container.querySelector('.ql-picker-options').children[this.select.selectedIndex];
 | 
						|
      option = this.select.options[this.select.selectedIndex];
 | 
						|
      this.selectItem(item);
 | 
						|
    } else {
 | 
						|
      this.selectItem(null);
 | 
						|
    }
 | 
						|
    let isActive = option != null && option !== this.select.querySelector('option[selected]');
 | 
						|
    this.label.classList.toggle('ql-active', isActive);
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
export default Picker;
 |