com.thecoderscorner.menu.domain.util.MenuItemHelper Class Reference

Static Public Member Functions
static< T > Optional< T >	visitWithResult (MenuItem item, AbstractMenuItemVisitor< T > visitor)
static SubMenuItem	asSubMenu (MenuItem item)
static boolean	isRuntimeStructureNeeded (MenuItem item)
static MenuItemBuilder	builderWithExisting (MenuItem item)
static MenuItem	createFromExistingWithId (MenuItem selected, int newId)
static int	eepromSizeForItem (MenuItem item)
static AnyMenuState	stateForMenuItem (AnyMenuState existingState, MenuItem item, Object val)
static AnyMenuState	stateForMenuItem (AnyMenuState existingState, MenuItem item, Object val, boolean changed)
static Optional< AnyMenuState >	applyIncrementalValueChange (MenuItem item, int delta, MenuTree tree)
static AnyMenuState	stateForMenuItem (MenuItem item, Object v, boolean changed, boolean active)
static void	setMenuState (MenuItem item, Object value, MenuTree tree)
static< T > T	getValueFor (MenuItem item, MenuTree tree, T def)
static Optional< BootItemMenuCommand<?, ?> >	getBootMsgForItem (MenuItem item, SubMenuItem parent, MenuTree tree)
static Object	getValueFor (MenuItem item, MenuTree tree)
static Object	getDefaultFor (MenuItem item)

Detailed Description

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.

Member Function Documentation

applyIncrementalValueChange()

static Optional<AnyMenuState> com.thecoderscorner.menu.domain.util.MenuItemHelper.applyIncrementalValueChange ( MenuItem  item, int  delta, MenuTree  tree  )

static

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

asSubMenu()

static SubMenuItem com.thecoderscorner.menu.domain.util.MenuItemHelper.asSubMenu ( MenuItem  item )

static

Returns the menu item as a sub menu or null

Parameters

item	the possible sub menu

Returns

the sub menu, or null.

createFromExistingWithId()

static MenuItem com.thecoderscorner.menu.domain.util.MenuItemHelper.createFromExistingWithId ( MenuItem  selected, int  newId  )

static

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()

static int com.thecoderscorner.menu.domain.util.MenuItemHelper.eepromSizeForItem ( MenuItem  item )

static

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.

getBootMsgForItem()

static Optional<BootItemMenuCommand<?, ?> > com.thecoderscorner.menu.domain.util.MenuItemHelper.getBootMsgForItem ( MenuItem  item, SubMenuItem  parent, MenuTree  tree  )

static

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()

static Object com.thecoderscorner.menu.domain.util.MenuItemHelper.getDefaultFor ( MenuItem  item )

static

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

getValueFor() [1/2]

static Object com.thecoderscorner.menu.domain.util.MenuItemHelper.getValueFor ( MenuItem  item, MenuTree  tree  )

static

This gets the value from the tree state, if it is not available calls getDefaultValue Same as getValueFor(item, tree, defVal) but this just calls getDefaultFor(..) to get the default.

Parameters

item	the item to get the state of
tree	the tree holding the state

Returns

the items current value, or the default.

getValueFor() [2/2]

static <T> T com.thecoderscorner.menu.domain.util.MenuItemHelper.getValueFor ( MenuItem  item, MenuTree  tree, T  def  )

static

Gets the value from the tree or the default provided

Parameters

item	the item
tree	the tree to lookup in
def	the default item (getDefaultFor can get the default automatically)
<T>	the type is inferred from the default parameter

Returns

the item looked up, or the default.

isRuntimeStructureNeeded()

static boolean com.thecoderscorner.menu.domain.util.MenuItemHelper.isRuntimeStructureNeeded ( MenuItem  item )

static

Check if the item is based on a runtime item

Parameters

item	the item to check

Returns

true if runtime based, otherwise false.

setMenuState()

static void com.thecoderscorner.menu.domain.util.MenuItemHelper.setMenuState ( MenuItem  item, Object  value, MenuTree  tree  )

static

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

stateForMenuItem() [1/3]

static AnyMenuState com.thecoderscorner.menu.domain.util.MenuItemHelper.stateForMenuItem ( AnyMenuState  existingState, MenuItem  item, Object  val  )

static

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() [2/3]

static AnyMenuState com.thecoderscorner.menu.domain.util.MenuItemHelper.stateForMenuItem ( AnyMenuState  existingState, MenuItem  item, Object  val, boolean  changed  )

static

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

stateForMenuItem() [3/3]

static AnyMenuState com.thecoderscorner.menu.domain.util.MenuItemHelper.stateForMenuItem ( MenuItem  item, Object  v, boolean  changed, boolean  active  )

static

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

visitWithResult()

static <T> Optional<T> com.thecoderscorner.menu.domain.util.MenuItemHelper.visitWithResult ( MenuItem  item, AbstractMenuItemVisitor< T >  visitor  )

static

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.

Parameters

item	the item to be visited
visitor	the visitor that will be used
<T>	the return type

Returns

an optional of the return type, set to empty unless setResult was called.

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The documentation for this class was generated from the following file:

• src/main/java/com/thecoderscorner/menu/domain/util/MenuItemHelper.java