keydown: function()

in site/semantic/src/definitions/modules/dropdown.js [1276:1459]


          keydown: function(event) {
            var
              pressedKey    = event.which,
              isShortcutKey = module.is.inObject(pressedKey, keys)
            ;
            if(isShortcutKey) {
              var
                $currentlySelected = $item.not(selector.unselectable).filter('.' + className.selected).eq(0),
                $activeItem        = $menu.children('.' + className.active).eq(0),
                $selectedItem      = ($currentlySelected.length > 0)
                  ? $currentlySelected
                  : $activeItem,
                $visibleItems = ($selectedItem.length > 0)
                  ? $selectedItem.siblings(':not(.' + className.filtered +')').addBack()
                  : $menu.children(':not(.' + className.filtered +')'),
                $subMenu              = $selectedItem.children(selector.menu),
                $parentMenu           = $selectedItem.closest(selector.menu),
                inVisibleMenu         = ($parentMenu.hasClass(className.visible) || $parentMenu.hasClass(className.animating) || $parentMenu.parent(selector.menu).length > 0),
                hasSubMenu            = ($subMenu.length> 0),
                hasSelectedItem       = ($selectedItem.length > 0),
                selectedIsSelectable  = ($selectedItem.not(selector.unselectable).length > 0),
                delimiterPressed      = (pressedKey == keys.delimiter && settings.allowAdditions && module.is.multiple()),
                isAdditionWithoutMenu = (settings.allowAdditions && settings.hideAdditions && (pressedKey == keys.enter || delimiterPressed) && selectedIsSelectable),
                $nextItem,
                isSubMenuItem,
                newIndex
              ;
              // allow selection with menu closed
              if(isAdditionWithoutMenu) {
                module.verbose('Selecting item from keyboard shortcut', $selectedItem);
                module.event.item.click.call($selectedItem, event);
                if(module.is.searchSelection()) {
                  module.remove.searchTerm();
                }
              }

              // visible menu keyboard shortcuts
              if( module.is.visible() ) {

                // enter (select or open sub-menu)
                if(pressedKey == keys.enter || delimiterPressed) {
                  if(pressedKey == keys.enter && hasSelectedItem && hasSubMenu && !settings.allowCategorySelection) {
                    module.verbose('Pressed enter on unselectable category, opening sub menu');
                    pressedKey = keys.rightArrow;
                  }
                  else if(selectedIsSelectable) {
                    module.verbose('Selecting item from keyboard shortcut', $selectedItem);
                    module.event.item.click.call($selectedItem, event);
                    if(module.is.searchSelection()) {
                      module.remove.searchTerm();
                    }
                  }
                  event.preventDefault();
                }

                // sub-menu actions
                if(hasSelectedItem) {

                  if(pressedKey == keys.leftArrow) {

                    isSubMenuItem = ($parentMenu[0] !== $menu[0]);

                    if(isSubMenuItem) {
                      module.verbose('Left key pressed, closing sub-menu');
                      module.animate.hide(false, $parentMenu);
                      $selectedItem
                        .removeClass(className.selected)
                      ;
                      $parentMenu
                        .closest(selector.item)
                          .addClass(className.selected)
                      ;
                      event.preventDefault();
                    }
                  }

                  // right arrow (show sub-menu)
                  if(pressedKey == keys.rightArrow) {
                    if(hasSubMenu) {
                      module.verbose('Right key pressed, opening sub-menu');
                      module.animate.show(false, $subMenu);
                      $selectedItem
                        .removeClass(className.selected)
                      ;
                      $subMenu
                        .find(selector.item).eq(0)
                          .addClass(className.selected)
                      ;
                      event.preventDefault();
                    }
                  }
                }

                // up arrow (traverse menu up)
                if(pressedKey == keys.upArrow) {
                  $nextItem = (hasSelectedItem && inVisibleMenu)
                    ? $selectedItem.prevAll(selector.item + ':not(' + selector.unselectable + ')').eq(0)
                    : $item.eq(0)
                  ;
                  if($visibleItems.index( $nextItem ) < 0) {
                    module.verbose('Up key pressed but reached top of current menu');
                    event.preventDefault();
                    return;
                  }
                  else {
                    module.verbose('Up key pressed, changing active item');
                    $selectedItem
                      .removeClass(className.selected)
                    ;
                    $nextItem
                      .addClass(className.selected)
                    ;
                    module.set.scrollPosition($nextItem);
                    if(settings.selectOnKeydown && module.is.single()) {
                      module.set.selectedItem($nextItem);
                    }
                  }
                  event.preventDefault();
                }

                // down arrow (traverse menu down)
                if(pressedKey == keys.downArrow) {
                  $nextItem = (hasSelectedItem && inVisibleMenu)
                    ? $nextItem = $selectedItem.nextAll(selector.item + ':not(' + selector.unselectable + ')').eq(0)
                    : $item.eq(0)
                  ;
                  if($nextItem.length === 0) {
                    module.verbose('Down key pressed but reached bottom of current menu');
                    event.preventDefault();
                    return;
                  }
                  else {
                    module.verbose('Down key pressed, changing active item');
                    $item
                      .removeClass(className.selected)
                    ;
                    $nextItem
                      .addClass(className.selected)
                    ;
                    module.set.scrollPosition($nextItem);
                    if(settings.selectOnKeydown && module.is.single()) {
                      module.set.selectedItem($nextItem);
                    }
                  }
                  event.preventDefault();
                }

                // page down (show next page)
                if(pressedKey == keys.pageUp) {
                  module.scrollPage('up');
                  event.preventDefault();
                }
                if(pressedKey == keys.pageDown) {
                  module.scrollPage('down');
                  event.preventDefault();
                }

                // escape (close menu)
                if(pressedKey == keys.escape) {
                  module.verbose('Escape key pressed, closing dropdown');
                  module.hide();
                }

              }
              else {
                // delimiter key
                if(delimiterPressed) {
                  event.preventDefault();
                }
                // down arrow (open menu)
                if(pressedKey == keys.downArrow && !module.is.visible()) {
                  module.verbose('Down key pressed, showing dropdown');
                  module.select.firstUnfiltered();
                  module.show();
                  event.preventDefault();
                }
              }
            }
            else {
              if( !module.has.search() ) {
                module.set.selectedLetter( String.fromCharCode(pressedKey) );
              }
            }
          }