xref: /external/chromium_org/third_party/polymer/components-chromium/core-selection/core-selection-extracted.js

    Polymer('core-selection', {
      /**
       * If true, multiple selections are allowed.
       *
       * @attribute multi
       * @type boolean
       * @default false
       */
      multi: false,
      ready: function() {
        this.clear();
      },
      clear: function() {
        this.selection = [];
      },
      /**
       * Retrieves the selected item(s).
       * @method getSelection
       * @returns Returns the selected item(s). If the multi property is true,
       * getSelection will return an array, otherwise it will return
       * the selected item or undefined if there is no selection.
      */
      getSelection: function() {
        return this.multi ? this.selection : this.selection[0];
      },
      /**
       * Indicates if a given item is selected.
       * @method isSelected
       * @param {any} item The item whose selection state should be checked.
       * @returns Returns true if `item` is selected.
      */
      isSelected: function(item) {
        return this.selection.indexOf(item) >= 0;
      },
      setItemSelected: function(item, isSelected) {
        if (item !== undefined && item !== null) {
          if (isSelected) {
            this.selection.push(item);
          } else {
            var i = this.selection.indexOf(item);
            if (i >= 0) {
              this.selection.splice(i, 1);
            }
          }
          this.fire("core-select", {isSelected: isSelected, item: item});
        }
      },
      /**
       * Set the selection state for a given `item`. If the multi property
       * is true, then the selected state of `item` will be toggled; otherwise
       * the `item` will be selected.
       * @method select
       * @param {any} item: The item to select.
      */
      select: function(item) {
        if (this.multi) {
          this.toggle(item);
        } else if (this.getSelection() !== item) {
          this.setItemSelected(this.getSelection(), false);
          this.setItemSelected(item, true);
        }
      },
      /**
       * Toggles the selection state for `item`.
       * @method toggle
       * @param {any} item: The item to toggle.
      */
      toggle: function(item) {
        this.setItemSelected(item, !this.isSelected(item));
      }
    });