Module com.thecoderscorner.tcmenu.javaapi
Package com.thecoderscorner.menu.domain.util

Class MenuItemHelper

java.lang.Object
com.thecoderscorner.menu.domain.util.MenuItemHelper
public class MenuItemHelper extends Object
A helper class for dealing with MenuItem objects. This class provides helpers for visiting menu items and returning a result. It also provides other helpers for dealing with items.

  • Constructor Details

    • MenuItemHelper

      public MenuItemHelper()

  • Method Details

    • visitWithResult

      public static <T> Optional<T> visitWithResult(MenuItem item, AbstractMenuItemVisitor<T> visitor)
      Visits a menu item calling the appropriate function for the type and collects the result that is set by calling your visitor's `setResult` method.
      Type Parameters:
      T - the return type
      Parameters:
      item - the item to be visited
      visitor - the visitor that will be used
      Returns:
      an optional of the return type, set to empty unless setResult was called.

    • asSubMenu

      public static SubMenuItem asSubMenu(MenuItem item)
      Returns the menu item as a sub menu or null
      Parameters:
      item - the possible sub menu
      Returns:
      the sub menu, or null.

    • isRuntimeStructureNeeded

      public static boolean isRuntimeStructureNeeded(MenuItem item)
      Check if the item is based on a runtime item
      Parameters:
      item - the item to check
      Returns:
      true if runtime based, otherwise false.

    • createFromExistingWithId

      public static MenuItem createFromExistingWithId(MenuItem selected, int newId)
      creates a copy of the menu item chosen, with the ID changed to newId
      Parameters:
      selected - the item to copy
      newId - the ID for the copy
      Returns:
      the newly created item

    • eepromSizeForItem

      public static int eepromSizeForItem(MenuItem item)
      Gets the size of the eeprom storage for a given element type
      Parameters:
      item - the item to determine eeprom size for
      Returns:
      the eeprom storage needed.

    • stateForMenuItem

      public static AnyMenuState stateForMenuItem(AnyMenuState existingState, MenuItem item, Object val)
      Get a new state object based on an existing state with a new value keeping all exising other values
      Parameters:
      existingState - the existing state object
      item - the item
      val - the value
      Returns:
      a new menu state object based on the parameters

    • stateForMenuItem

      public static AnyMenuState stateForMenuItem(AnyMenuState existingState, MenuItem item, Object val, boolean changed)
      Get the state for an existing state with a new value, changing the changed state
      Parameters:
      existingState - the existing state object
      item - the item
      val - the changed value
      changed - the new change status
      Returns:
      a new state object based on the parameters

    • applyIncrementalValueChange

      public static Optional<AnyMenuState> applyIncrementalValueChange(MenuItem item, int delta, MenuTree tree)
      Try and apply an incremental delta value update to a menu tree. This works for integer, enum and scroll items, it loads the existing value and tries to apply the delta offset, if the min/max would not be exceeded.
      Parameters:
      item - the item to change
      delta - the delta amount
      tree - the tree the item belongs to
      Returns:
      a new item if the operation was possible, otherwise empty

    • stateForMenuItem

      public static AnyMenuState stateForMenuItem(MenuItem item, Object v, boolean changed, boolean active)
      Create a menu state for a given item with a value update. We try pretty hard to convert whatever comes in for the value into a new state.
      Parameters:
      item - the item to create the state for
      v - the value
      changed - the changed status
      active - the active status
      Returns:
      the new menu state

    • setMenuState

      public static void setMenuState(MenuItem item, Object value, MenuTree tree)
      Set the state in the tree for an item with a new value, setting it changed if it genuinely has.
      Parameters:
      item - the item
      value - the replacement value
      tree - the tree to change

    • getValueFor

      public static <T> T getValueFor(MenuItem item, MenuTree tree, T def)
      Gets the value from the tree or the default provided
      Type Parameters:
      T - the type is inferred from the default parameter
      Parameters:
      item - the item
      tree - the tree to lookup in
      def - the default item (getDefaultFor can get the default automatically)
      Returns:
      the item looked up, or the default.

    • getBootMsgForItem

      public static Optional<BootItemMenuCommand<?,?>> getBootMsgForItem(MenuItem item, SubMenuItem parent, MenuTree tree)
      Can be used during boot sequences to get a suitable boot item for a menu item
      Parameters:
      item - the item
      parent - the parent
      tree - the tree it belongs to
      Returns:
      either a boot item or empty

    • getDefaultFor

      public static Object getDefaultFor(MenuItem item)
      Gets the default item value for a menu item, such that the value could be used in call to set state.
      Parameters:
      item - the item
      Returns:
      the default value