React multiselect

description.md

React multiselect tag

demo: https://codepen.io

Examples:

simple select with searchable, multiple and creatable:

  <CustomSelect
    items={items}
    multiple
    onChange={hadnleChange}
    placeholder="Select value, please..."
    searchable
    selectedIds={[8, 7]}
  />

API

Attributes to cusomize your Select:

• items - recursive or plain tree of menu elements;
• multiple - enable multiselect;
• searchable - presents a text input for search elements by entering text;
• creatable - enable new menu items creation if user entering unique textin search field;
• onChange - call handleChange with parameters handleChange(element, value);
• placeholder - text, which shown when nothing selected;
• selectedIds - list ids of preselected items;
• taggable - enable render selection as a tags;

multiselectTag.jsx

const constants = {
  CLOSED: 'CLOSED',
  OPENED: 'OPENED',
}

const items = [
  {
    children: [
      {
        children: [
          {
            id: 6,
            name: 'Green',
          },
          {
            id: 7,
            name: 'Blue',
          },
          {
            children: [
              {
                id: 9,
                name: 'The push() method adds new items to the end of an array, and returns the new length.',
              },
              {
                id: 10,
                name: 'Hot',
              },
              {
                id: 11,
                name: 'Cold',
              },
            ],
            id: 8,
            name: 'Red',
          },
        ],
        id: 3,
        name: 'Moscow',
      },
      {
        id: 4,
        name: 'New York',
      },
      {
        id: 5,
        name: 'Paris',
      },
    ],
    id: 1,
    name: 'Accounting',
  },
  {
    id: 2,
    name: 'Management',
  }
]

class CustomSelect extends React.Component {
  constructor(props) {
    super(props)
    const { multiple, selectedIds } = props
    this.prepareItems()

    this.state = {
      popupState: constants.CLOSED,
      searchedText: undefined,
      selectedIds: multiple ? selectedIds : [selectedIds[0]].filter((x) => x),
    }
  }

  /**
   * Add item to flatten menu items
   */
  addItem = ({ name }) => {
    const ids = this.itemsFlattenSource.filter((x) => x).map((item) => item.item.id)
    const id = Math.max(...ids) + 1
    items.push({
      id,
      name,
    })
    this.toggleItem({ id })
    this.prepareItems()
  }

  /**
   * Render first tag as editor component which can edit a search text for filter items or add a tag,
   * if this.props.creatable === true
   */
  editorTag = ({ itemsEmpty }) => {
    const { creatable } = this.props
    const { searchedText } = this.state
    return (
      <span
        className={[
          "custom-select--head-text--editor-tag",
          `${creatable && itemsEmpty ? "custom-select--head-text--editor-tag--empty-list" : ""}`,
        ].filter((x) => x).join(" ")}
      >
        <input
          defaultValue={searchedText}
          onChange={this.searchByText}
          type="text"
        />
        <span
          className={[
            `custom-select--head-text--editor-tag${creatable && itemsEmpty ? "--empty-list" : ""}--control-button`,
          ].join(" ")}
          onClick={() => this.addItem({ name: searchedText })}
        />
      </span>
    )
  }

  /**
   * Implement non recursive selecting from recursive tree items
   * @param {Number} id - item id
   * @param {Array} items - array of items
   */
  getDeep = ({ id, items }) => {
    let selectedItem, selectedLevel
    this.traverseDeep({
      callback: ({ item, level }) => {
        if (item.id === id) {
          selectedItem = item
          selectedLevel = level
        }
      },
      items,
    })
    return { selectedItem, selectedLevel }
  }

  /**
   * Highlight text to react element
   * @param {RegExp} regexp - regular expression to highlight
   * @param {String} text - text to highlight
   * @returns {React.element}
   */
  highlightText = ({ regexp, text }) => {
    const matchedText = (text.match(regexp) || [])[0]
    if (!matchedText) {
      return text
    }
    const items = text.split(regexp)
    return items.map((item, index) => {
      return (
        <React.Fragment key={`item--${index}`}>
          {item}
          {
            index < items.length - 1 && (
              <strong>{matchedText}</strong>
            )
          }
        </React.Fragment>
      )
    })
  }

  /**
   * Render array of selected items as tags
   * @param {Array} ids - id of selected items
   * @param {Bool} itemsEmpty - check if no items to select
   */
  mapSelectedItems = ({ ids, itemsEmpty }) => {
    const { itemsFlattenSource } = this
    const { multiple, placeholder, searchable } = this.props
    return (
      <React.Fragment>
        {searchable && this.editorTag({ itemsEmpty })}
        {
          !ids.length && (
            <span
              className="custom-select--head-text--placeholder"
            >
              {placeholder}
            </span>
          )
        }
        {
          (multiple ? ids : [ids[0]].filter((x) => x)).map((id) => {
            const item = itemsFlattenSource.find((item) => {
              return item.item.id === id
            })
            if (!item) {
              return null
            }
            const { item: selectedItem, level: selectedLevel } = item
            return (
              <span
                className="custom-select--head-text--selected-tag"
                key={`selectedTag--${id}`}
              >
                ({selectedLevel}) - {selectedItem.name}
                <span
                  className="custom-select--head-text--selected-tag--close-btn"
                  onClick={(event) => this.toggleItem({ event, id })}
                >
                  X
                </span>
              </span>
            )
          })
        }
      </React.Fragment>
    )
  }

  /**
   * Filter menu items by searched text
   * @returns {Array}
   */
  prepareItems = () => {
    this.itemsFlattenSource = this.toFlatten({ items })
  }

  /**
   * Repeats symbol count times
   * @param {Number} count - count of repeats
   * @param {String} symbol - symbol
   * @return {String}
   */
  repeat = ({ count, symbol = '-' }) => {
    return Array(count + 1).join(symbol)
  }

  /**
   * set searchedText value in state
   * @param {Event} event - event of text imput
   */
  searchByText = (event) => {
    const { OPENED } = constants
    const { value: searchedText } = event.target
    const newStateData = {
      searchedText,
    }
    if (this.state.popupState != OPENED) {
      newStateData.popupState = OPENED
    }
    this.setState(newStateData)
    this.prepareItems()
  }

  /**
   * Convert array of recursive tree of menu elements to flatten array
   * @param {Array} items - recursive tree of menu items
   */
  toFlatten = ({ items }) => {
    const itemsFlatten = []
    this.traverseDeep({
      callback: ({ item, level }) => {
        itemsFlatten.push({ item: { id: item.id, name: item.name }, level })
      },
      items,
    })
    return itemsFlatten
  }

  /**
   * Adds value to array if it not exists yet or remove if value includes to array
   * @param {Array} array - array
   * @param {String} value - toggled value
   * @returns {Array}
   */
  toggleArrayValue = ({ array, value }) => {
    const elementIndex = array.findIndex((element) => {
      return element === value
    })
    if (elementIndex >= 0) {
      array.splice(elementIndex, 1)
    } else {
      array.push(value)
    }
    return array
  }

  /**
   * toggle option to selected or not selected
   */
  toggleItem = ({ event = undefined, id }) => {
    if (event) {
      event.stopPropagation()
    }
    const { multiple } = this.props
    let { selectedIds } = this.state
    if (multiple) {
      selectedIds = this.toggleArrayValue({
        array: selectedIds,
        value: id,
      })
    } else if (selectedIds.includes(id)) {
      selectedIds = []
    } else {
      selectedIds = [id]
    }
    const { CLOSED } = constants
    this.setState({
      popupState: CLOSED,
      selectedIds,
    })
    this.props.onChange(this, selectedIds)
  }

  get value() {
    const { selectedIds } = this.state
    return selectedIds
  }

  /**
   * Open / close select menu popup
   */
  togglePopup = () => {
    const { popupState } = this.state
    const { CLOSED, OPENED } = constants
    this.setState({ popupState: popupState === OPENED ? CLOSED : OPENED })
  }

  /**
   * Non-recurcive iteration over recursive tree of array elements
   * @param {Function} callback - callback for each item
   * @param {Array} items - recursive tree of menu items
   */
  traverseDeep = ({ callback, items }) => {
    const stack = items.map((item) => {
      return { item, level: 0 }
    })

    while (stack.length) {
      const { item, level } = stack[0]
      const { children } = item
      if (item.id && item.name) {
        callback({ item, level })
      }
      if (children) {
        const nextLevelItems = item.children.map((nextLevelItem) => {
          return { item: nextLevelItem, level: level + 1 }
        }) || []
        stack.splice(1, 0, ...nextLevelItems)
      }
      stack.shift()
    }
    return undefined
  }

  render() {
    const { popupState, searchedText, selectedIds } = this.state
    const { multiple, taggable } = this.props
    const { itemsFlattenSource } = this
    const regexp = new RegExp(searchedText, 'i')
    const itemsEmpty = !itemsFlattenSource.filter((item) => regexp.test(item.item.name)).length

    return (
      <div>
        <div
          className={[
            "custom-select",
            !multiple && !taggable && "custom-select--non-tagged",
          ].filter((x) => x).join(" ")}
        >
          <div
            className={[
              "custom-select--head",
              `custom-select--head-${popupState.toLowerCase()}`
            ].join(" ")}
            onClick={this.togglePopup}
          >
            <div className="custom-select--head-text">
              {this.mapSelectedItems({ ids: selectedIds, itemsEmpty })}
            </div>
          </div>
        </div>
        <div
          className={[
            "custom-select--popup",
            `custom-select--popup-${popupState.toLowerCase()}`,
          ].join(" ")}
        >
          {
            itemsFlattenSource.map(({ item, level }, index) => {
              if (searchedText) {
                if (!regexp.test(item.name)) {
                  return null
                }
              }

              return (
                <div
                  className={[
                    "custom-select--popup-option",
                    selectedIds.includes(item.id) ? "custom-select--popup-option-selected" : "",
                  ].join(" ")}
                  key={`option_${index}`}
                  onClick={() => this.toggleItem({ id: item.id })}
                >
                  {this.repeat({ count: level + 2 })}&nbsp;
                  {
                    searchedText ? this.highlightText({ regexp, text: item.name }) : (
                      <span>{item.name}</span>
                    )
                  }
                </div>
              )
            })
          }
        </div>
      </div>
    )
  }
}

CustomSelect.propTypes = {
  creatable: PropTypes.bool,      // If user enter unexisted item name - then button add appear to adding new tag
  items: PropTypes.shape({
    children: PropTypes.shape({}),
    id: PropTypes.number,
    name: PropTypes.string,
  }),                             // Recursive tree of menu elements
  multiple: PropTypes.bool,       // Enable multiple selection
  onChange: PropTypes.func,       // On change handler
  placeholder: PropTypes.string,  // select placeholder
  searchable: PropTypes.bool,     // User can filtering items by text in item names
  selectedIds: PropTypes.arrayOf(PropTypes.number),  // id of selected items
  taggable: PropTypes.bool,       // Selected items rendered as tags
}

const SelectedIds = ({ selectedIds }) => {
  return (
    <div>
      {
        selectedIds.length > 0 ? (
          <div>ids selected: {selectedIds.join(', ')}</div>
        ) : (
          <div>Nothing selected</div>
        )
      }
    </div>
  )
}

class CustomSelectDemo extends React.Component {
  constructor(props) {
    super(props)
    this.state = {
      selectedIds1: [8],
      selectedIds2: [8],
      selectedIds3: [8, 7],
      selectedIds4: [8, 7],
      selectedIds5: [8, 7]
    }
  }

  handleSelectChange = (itemName) => {
    return (element, value) => {
      const data = {}
      data[itemName] = value
      this.setState(data)
      console.log(`We can get selected value from CustomSelect component: value=${element.value}`)
    }
  }

  render() {
    const {
      selectedIds1,
      selectedIds2,
      selectedIds3,
      selectedIds4,
      selectedIds5,
    } = this.state

    return (
      <React.Fragment>
        <h1>
          <a href="https://gist.github.com/r72cccp/ee6672c65ebbe8947085acedf0ed1349">React select</a> using examples
        </h1>

        <div className="examples-list">
          <span className="examples-list--card">
            <h2>React select</h2>
            <SelectedIds selectedIds={selectedIds1}/>

            <CustomSelect
              items={items}
              onChange={this.handleSelectChange('selectedIds1')}
              placeholder="Select value"
              selectedIds={selectedIds1}
            />
          </span>

          <span className="examples-list--card">
            <h2>React select with search</h2>
            <SelectedIds selectedIds={selectedIds2}/>
            <CustomSelect
              items={items}
              onChange={this.handleSelectChange('selectedIds2')}
              placeholder="Select value"
              searchable
              selectedIds={selectedIds2}
              taggable
            />
          </span>

          <span className="examples-list--card">
            <h2>React multiple select</h2>
            <SelectedIds selectedIds={selectedIds3}/>
            <CustomSelect
              items={items}
              onChange={this.handleSelectChange('selectedIds3')}
              multiple
              placeholder="Select values"
              selectedIds={selectedIds3}
            />
          </span>

          <span className="examples-list--card">
            <h2>React multiple select with search</h2>
            <SelectedIds selectedIds={selectedIds4}/>
            <CustomSelect
              items={items}
              multiple
              onChange={this.handleSelectChange('selectedIds4')}
              placeholder="Select values"
              searchable
              selectedIds={selectedIds4}
            />
          </span>

          <span className="examples-list--card">
            <h2>React multiple select with search and create tags</h2>
            <SelectedIds selectedIds={selectedIds5}/>
            <CustomSelect
              creatable
              items={items}
              multiple
              onChange={this.handleSelectChange('selectedIds5')}
              placeholder="Select values"
              searchable
              selectedIds={selectedIds5}
            />
          </span>
        </div>
      </React.Fragment>
    )
  }
}

ReactDOM.render((
  <CustomSelectDemo />
), document.querySelector("#app"))

multiselectTag.less

@width: 300px;
@height: 32px;
@backgroundColor: white;
body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
  min-height: 300px;
  * {
    box-sizing: border-box;
  }
  
  .examples-list {
    display: flex;
    flex-wrap: wrap;
    
    &--card {
      margin: 10px;
      padding: 20px;
      background-color: #eee;
      max-width: 350px;
    }
  }
}

.custom-select {
  cursor: pointer;
  border: 2px solid lightgray;
  background-color: @backgroundColor;
  font-size: @height - 8px;
  justify-content: flex-start;
  max-width: @width;

  &--head {
    position: relative;
    outline: 2px solid navy;
    border-radius: 4px;
    padding: 2px @height 0px 2px;

    &-text {
      overflow: auto;
      display: flex;
      flex-direction: row;
      align-content: flex-start;
      align-items: flex-start;
      flex-wrap: wrap;
      
      &--placeholder {
        color: lightgray;
        font-size: @height - 12px;
        padding: 4px;
      }
  
      &--selected-tag, &--editor-tag {
        margin: 0px 2px 2px 0px;
        min-height: @height - 2px;
        font-size: @height - 16px;
        line-height: @height - 15px;
        max-width: (@width - 32px);
        border-radius: 4px;
        position: relative;

        &:hover {
          color: white;
          background-color: green;
        }

        &--close-btn {
          position: absolute;
          right: 2px;
          top: 2px;
          border-radius: 2px;
          padding: 2px 4px;
          font-size: @height - 18px;
          &:hover {
            background-color: white;
            color: crimson;
          }
        }
      }
      &--selected-tag {
        padding: 4px @height + 2px 2px 4px;
        background-color: navy;
        border: 2px solid gray;
        color: white;
        cursor: pointer;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
      }
      
      &--editor-tag {
        padding: 2px;
        background-color: white;
        border: 2px solid gray;
        color: gray;
        cursor: text;
        margin-bottom: 2px;
        min-width: 100px;
        
        input {
          border: 0px;
          outline: 0px;
        }
        
        &--control-button {
          position: absolute;
          right: 0px;
          top: 0px;          
          
          &:after {
            content: "🔍";
            position: absolute;
            right: 2px;
            top: 2px;
            padding: 2px;
            color: lightgray;
            text-decoration: bold;
          }
        }

        &:hover {
          background-color: white;
          color: black;
        }
        
        &--empty-list {
          &--control-button {
            &:after {
              content: '+';
              position: absolute;
              right: 4px;
              cursor: pointer;
              line-height: 16px;
              padding: 0 4px;
              top: 5px;
              border: 2px solig lightgray;
              border-radius: 2px;
            }
          }
          
          &--control-button {
            &:hover {
              &:after {
                color: white;
                background-color: green;
                text-decoration: bold;
              }
            }
          }
        }
      }
    }

    &-opened, &-closed {
      &:after {
        position: absolute;
        transition: all .1s;
        background-color: white;
        line-height: 12px;
        right: 8px;
        content: '^';
      }
    }

    &-opened {
      &:after {
        transform: rotate(0deg);
        top: 12px;
      }
    }

    &-closed {
      &:after {
        transform: rotate(180deg);
        top: 4px;
      }
    }
  }

  &--popup {
    flex-direction: column;
    overflow-y: auto;
    background-color: @backgroundColor;
    width: @width;
    transition: height .1s;

    &-closed {
      height: 0px;
    }

    &-opened {
      border: 2px solid lightgray;
      height: 200px;
    }

    &-option {
      cursor: pointer;
      padding: 8px;
      margin: 2px 0;
      strong {
        color: crimson;
      }

      &:hover {
        background-color: black;
        color: white;
      }

      &-selected {
        background-color: navy;
        color: white;

        &:hover {
          background-color: crimson !important;
          color: white !important;
          strong {
            color: navy;
          }
        }
      }
    }
  }
}

.custom-select--non-tagged {
  .custom-select--head {
    padding: 0px;
    .custom-select--head-text {
      .custom-select--head-text--selected-tag {
        width: 100%;
        margin: 0px;
        border: 0px;
        padding: 6px;
        font-size: 16px;
        border-radius: 0px;
        
        &--close-btn {
          line-height: @height - 10px;
          padding-left: 8px;
          padding-right: 8px;
        }
      }
    }
  }
}

how to pass selected items to api

Good question. Thank you!
In the form as it is now, this cannot be done in any way.
I'll fix it tonight - add an onChange handler to the component:

const handleSelectChange = (value) => {
  console.log({ value })
}

<CustomSelect
  creatable
  items={items}
  multiple
  onChange={handleSelectChange}
  placeholder="Select values"
  searchable
  selectedIds={[8, 7]}
 />