_onSelectedItemsChanged(selectedItems) {
    if (selectedItems.length > 0) {
      if (this.$.placeholder.style.display != 'none') {
        this.$.placeholder.style.display = 'none';
      }
    } else {
      if (this.$.placeholder.style.display == 'none') {
        this.$.placeholder.style.display = 'block';
      }
    }
  }
/** Called every time the selected items changed to show or hide the placeholder. */
Called every time the selected items changed to show or hide the placeholder.
Called every time the selected items changed to show or hide the placeholder .
_onSelectedItemsChanged(selectedItems) {
    if (selectedItems.length > 0) {
      if (this.$.placeholder.style.display != 'none') {
        this.$.placeholder.style.display = 'none';
      }
    } else {
      if (this.$.placeholder.style.display == 'none') {
        this.$.placeholder.style.display = 'block';
      }
    }
  }
_onSelectedItemsChanged ( selectedItems ) { if ( selectedItems . length > 0 ) { if ( this . $ . placeholder . style . display != 'none' ) { this . $ . placeholder . style . display = 'none' ; } } else { if ( this . $ . placeholder . style . display == 'none' ) { this . $ . placeholder . style . display = 'block' ; } } }
Called every time the selected items changed to show or hide the placeholder.
Called every time the selected items changed to show or hide the placeholder .