This is an organizational class that can update and render a bunch of FlxBasics. NOTE: Although FlxGroup extends FlxBasic, it will not automatically add itself to the global collisions quad tree, it will only add its members.

Constructor

new(MaxSize:Int = 0)

Parameters:

MaxSize

Maximum amount of members allowed.

Variables

read onlylength:Int = 0

The number of entries in the members array. For performance and safety you should check this variable instead of members.length unless you really know what you're doing!

maxSize:Int

The maximum capacity of this group. Default is 0, meaning no max capacity, and the group can just grow.

read onlymembers:Array<T>

Array of all the members in this group.

Methods

add(Object:T):T

Adds a new FlxBasic subclass (FlxBasic, FlxSprite, Enemy, etc) to the group. FlxGroup will try to replace a null member of the array first. Failing that, FlxGroup will add it to the end of the member array. WARNING: If the group has a maxSize that has already been met, the object will NOT be added to the group!

Parameters:

Object

The object you want to add to the group.

Returns:

The same FlxBasic object that was passed in.

clear():Void

Remove all instances of FlxBasic subclasses (FlxSprite, FlxTileblock, etc) from the list. WARNING: does not destroy() or kill() any of these objects!

countDead():Int

Call this function to find out how many members of the group are dead.

Returns:

The number of FlxBasics flagged as dead. Returns -1 if group is empty.

countLiving():Int

Call this function to find out how many members of the group are not dead.

Returns:

The number of FlxBasics flagged as not dead. Returns -1 if group is empty.

destroy():Void

WARNING: A destroyed FlxBasic can't be used anymore. It may even cause crashes if it is still part of a group or state. You may want to use kill() instead if you want to disable the object temporarily only and revive() it later.

This function is usually not called manually (Flixel calls it automatically during state switches for all add()ed objects).

Override this function to null out variables manually or call destroy() on class members if necessary. Don't forget to call super.destroy()!

draw():Void

Automatically goes through and calls render on everything you added.

forEach(Function:T‑>Void, Recurse:Bool = false):Void

Applies a function to all members.

Parameters:

Function

A function that modifies one element at a time.

Recurse

Whether or not to apply the function to members of subgroups as well.

forEachAlive(Function:T‑>Void, Recurse:Bool = false):Void

Applies a function to all alive members.

Parameters:

Function

A function that modifies one element at a time.

Recurse

Whether or not to apply the function to members of subgroups as well.

forEachDead(Function:T‑>Void, Recurse:Bool = false):Void

Applies a function to all dead members.

Parameters:

Function

A function that modifies one element at a time.

Recurse

Whether or not to apply the function to members of subgroups as well.

forEachExists(Function:T‑>Void, Recurse:Bool = false):Void

Applies a function to all existing members.

Parameters:

Function

A function that modifies one element at a time.

Recurse

Whether or not to apply the function to members of subgroups as well.

forEachOfType<K>(ObjectClass:Class<K>, Function:K‑>Void, Recurse:Bool = false):Void

Applies a function to all members of type Class<K>.

Parameters:

ObjectClass

A class that objects will be checked against before Function is applied, ex: FlxSprite.

Function

A function that modifies one element at a time.

Recurse

Whether or not to apply the function to members of subgroups as well.

getFirstAlive():T

Call this function to retrieve the first object with dead == false in the group. This is handy for checking if everything's wiped out, or choosing a squad leader, etc.

Returns:

A FlxBasic currently flagged as not dead.

getFirstAvailable(?ObjectClass:Class<T>, Force:Bool = false):T

Call this function to retrieve the first object with exists == false in the group. This is handy for recycling in general, e.g. respawning enemies.

Parameters:

ObjectClass

An optional parameter that lets you narrow the results to instances of this particular class.

Force

Force the object to be an ObjectClass and not a super class of ObjectClass.

Returns:

A FlxBasic currently flagged as not existing.

getFirstDead():T

Call this function to retrieve the first object with dead == true in the group. This is handy for checking if everything's wiped out, or choosing a squad leader, etc.

Returns:

A FlxBasic currently flagged as dead.

getFirstExisting():T

Call this function to retrieve the first object with exists == true in the group. This is handy for checking if everything's wiped out, or choosing a squad leader, etc.

Returns:

A FlxBasic currently flagged as existing.

getFirstNull():Int

Call this function to retrieve the first index set to null. Returns -1 if no index stores a null object.

Returns:

An Int indicating the first null slot in the group.

getRandom(StartIndex:Int = 0, Length:Int = 0):T

Returns a member at random from the group.

Parameters:

StartIndex

Optional offset off the front of the array. Default value is 0, or the beginning of the array.

Length

Optional restriction on the number of values you want to randomly select from.

Returns:

A FlxBasic from the members list.

insert(position:Int, object:T):T

Inserts a new FlxBasic subclass (FlxBasic, FlxSprite, Enemy, etc) into the group at the specified position. FlxGroup will try to replace a null member at the specified position of the array first. Failing that, FlxGroup will insert it at the position of the member array. WARNING: If the group has a maxSize that has already been met, the object will NOT be inserted to the group!

Parameters:

position

The position in the group where you want to insert the object.

object

The object you want to insert into the group.

Returns:

The same FlxBasic object that was passed in.

inlineiterator(?filter:T‑>Bool):FlxTypedGroupIterator<T>

Iterates through every member.

kill():Void

Calls kill() on the group's members and then on the group itself. You can revive this group later via revive() after this.

recycle(?ObjectClass:Class<T>, ?ObjectFactory:Void‑>T, Force:Bool = false, Revive:Bool = true):T

Recycling is designed to help you reuse game objects without always re-allocating or "newing" them. It behaves differently depending on whether maxSize equals 0 or is bigger than 0.

maxSize > 0 / "rotating-recycling" (used by FlxEmitter): - at capacity: returns the next object in line, no matter its properties like alive, exists etc. - otherwise: returns a new object.

maxSize == 0 / "grow-style-recycling" - tries to find the first object with exists == false - otherwise: adds a new object to the members array

WARNING: If this function needs to create a new object, and no object class was provided, it will return null instead of a valid object!

Parameters:

ObjectClass

The class type you want to recycle (e.g. FlxSprite, EvilRobot, etc).

ObjectFactory

Optional factory function to create a new object if there aren't any dead members to recycle. If null, Type.createInstance() is used, which requires the class to have no constructor parameters.

Force

Force the object to be an ObjectClass and not a super class of ObjectClass.

Revive

Whether recycled members should automatically be revived (by calling revive() on them).

Returns:

A reference to the object that was created.

remove(Object:T, Splice:Bool = false):T

Removes an object from the group.

Parameters:

Object

The FlxBasic you want to remove.

Splice

Whether the object should be cut from the array entirely or not.

Returns:

The removed object.

replace(OldObject:T, NewObject:T):T

Replaces an existing FlxBasic with a new one. Does not do anything and returns null if the old object is not part of the group.

Parameters:

OldObject

The object you want to replace.

NewObject

The new object you want to use instead.

Returns:

The new object.

revive():Void

Calls revive() on the group's members and then on the group itself.

inlinesort(Function:Int‑>T‑>T‑>Int, Order:Int = FlxSort.ASCENDING):Void

Call this function to sort the group according to a particular value and order. For example, to sort game objects for Zelda-style overlaps you might call group.sort(FlxSort.byY, FlxSort.ASCENDING) at the bottom of your FlxState#update() override.

Parameters:

Function

The sorting function to use - you can use one of the premade ones in FlxSort or write your own using FlxSort.byValues() as a "backend".

Order

A constant that defines the sort order. Possible values are FlxSort.ASCENDING (default) and FlxSort.DESCENDING.

update(elapsed:Float):Void

Automatically goes through and calls update on everything you added.

Inherited Variables

Defined by FlxBasic

ID:Int = -1

IDs seem like they could be pretty useful, huh? They're not actually used for anything yet though.

active:Bool = true

Controls whether update() is automatically called by FlxState/FlxGroup.

alive:Bool = true

Useful state for many game objects - "dead" (!alive) vs alive. kill() and revive() both flip this switch (along with exists, but you can override that).

camera:FlxCamera

Gets ot sets the first camera of this object.

cameras:Array<FlxCamera>

This determines on which FlxCameras this object will be drawn. If it is null / has not been set, it uses FlxCamera.defaultCameras, which is a reference to FlxG.cameras.list (all cameras) by default.

exists:Bool = true

Controls whether update() and draw() are automatically called by FlxState/FlxGroup.

visible:Bool = true

Controls whether draw() is automatically called by FlxState/FlxGroup.

Inherited Methods

Defined by FlxBasic