API Reference

Class List

pc.LayoutGroupComponent

Extends: pc.Component

A LayoutGroupComponent enables the Entity to position and scale child pc.ElementComponents according to configurable layout rules.

Summary

Properties

alignmentSpecifies the horizontal and vertical alignment of child elements.
heightFittingIdentical to pc.LayoutGroupComponent#widthFitting but for the Y axis.
orientationWhether the layout should run horizontally or vertically.
paddingPadding to be applied inside the container before positioning any children.
reverseXReverses the order of children along the x axis.
reverseYReverses the order of children along the y axis.
spacingSpacing to be applied between each child element.
widthFittingFitting logic to be applied when positioning and scaling child elements.
wrapWhether or not to wrap children onto a new row/column when the size of the container is exceeded.

Inherited

Properties

enabledEnables or disables the component.
entityThe Entity that this Component is attached to
systemThe ComponentSystem used to create this Component

Methods

fireFire an event, all additional arguments are passed on to the event listener
hasEventTest if there are any handlers bound to an event name
offDetach an event handler from an event.
onAttach an event handler to an event
onceAttach an event handler to an event.

Details

Constructor

LayoutGroupComponent(system, entity)

Create a new LayoutGroupComponent

Parameters

systempc.LayoutGroupComponentSystemThe ComponentSystem that created this Component
entitypc.EntityThe Entity that this Component is attached to.

Properties

pc.Vec2alignment

Specifies the horizontal and vertical alignment of child elements. Values range from 0 to 1 where [0,0] is the bottom left and [1,1] is the top right.

NumberheightFitting

Identical to pc.LayoutGroupComponent#widthFitting but for the Y axis.

Numberorientation

Whether the layout should run horizontally or vertically.

pc.Vec4padding

Padding to be applied inside the container before positioning any children. Specified as left, bottom, right and top values.

BooleanreverseX

Reverses the order of children along the x axis.

BooleanreverseY

Reverses the order of children along the y axis.

pc.Vec2spacing

Spacing to be applied between each child element.

NumberwidthFitting

Fitting logic to be applied when positioning and scaling child elements. Can be one of the following:

  • pc.FITTING_NONE: Child elements will be rendered at their natural size.
  • pc.FITTING_STRETCH: When the natural size of all child elements does not fill the width of the container, children will be stretched to fit. The rules for how each child will be stretched are outlined below:
    1. Sum the pc.LayoutChildComponent#fitWidthProportion values of each child and normalize so that all values sum to 1.
    2. Apply the natural width of each child.
    3. If there is space remaining in the container, distribute it to each child based on the normalized pc.LayoutChildComponent#fitWidthProportion values, but do not exceed the pc.LayoutChildComponent#maxWidth of each child.
  • pc.FITTING_SHRINK: When the natural size of all child elements overflows the width of the container, children will be shrunk to fit. The rules for how each child will be stretched are outlined below:
    1. Sum the pc.LayoutChildComponent#fitWidthProportion values of each child and normalize so that all values sum to 1.
    2. Apply the natural width of each child.
    3. If the new total width of all children exceeds the available space of the container, reduce each child's width proportionally based on the normalized pc.LayoutChildComponent#fitWidthProportion values, but do not exceed the pc.LayoutChildComponent#minWidth of each child.
  • pc.FITTING_BOTH: Applies both STRETCH and SHRINK logic as necessary.

Booleanwrap

Whether or not to wrap children onto a new row/column when the size of the container is exceeded. Defaults to false, which means that children will be be rendered in a single row (horizontal orientation) or column (vertical orientation).

Note that setting wrap to true makes it impossible for the pc.FITTING_BOTH fitting mode to operate in any logical manner. For this reason, when wrap is true, a pc.LayoutGroupComponent#widthFitting or pc.LayoutGroupComponent#heightFitting mode of pc.FITTING_BOTH will be coerced to pc.FITTING_STRETCH.

Inherited

Properties

Booleanenabled

Enables or disables the component.

pc.Entityentity

The Entity that this Component is attached to

pc.ComponentSystemsystem

The ComponentSystem used to create this Component

Methods

fire(name, [arg1], [arg2], [arg3], [arg4], [arg5], [arg6], [arg7], [arg8])

Fire an event, all additional arguments are passed on to the event listener

obj.fire('test', 'This is the message');

Parameters

nameObjectName of event to fire
arg1*First argument that is passed to the event handler
arg2*Second argument that is passed to the event handler
arg3*Third argument that is passed to the event handler
arg4*Fourth argument that is passed to the event handler
arg5*Fifth argument that is passed to the event handler
arg6*Sixth argument that is passed to the event handler
arg7*Seventh argument that is passed to the event handler
arg8*Eighth argument that is passed to the event handler

Returns

pc.EventHandler Self for chaining.

hasEvent(name)

Test if there are any handlers bound to an event name

obj.on('test', function () { }); // bind an event to 'test'
obj.hasEvent('test'); // returns true
obj.hasEvent('hello'); // returns false

Parameters

nameStringThe name of the event to test

Returns

Boolean true if the object has handlers bound to the specified event name.

off([name], [callback], [scope])

Detach an event handler from an event. If callback is not provided then all callbacks are unbound from the event, if scope is not provided then all events with the callback will be unbound.

var handler = function () {
};
obj.on('test', handler);

obj.off(); // Removes all events
obj.off('test'); // Removes all events called 'test'
obj.off('test', handler); // Removes all handler functions, called 'test'
obj.off('test', handler, this); // Removes all hander functions, called 'test' with scope this

Parameters

nameStringName of the event to unbind
callbackpc.callbacks.HandleEventFunction to be unbound.
scopeObjectScope that was used as the this when the event is fired

Returns

pc.EventHandler Self for chaining.

on(name, callback, [scope])

Attach an event handler to an event

obj.on('test', function (a, b) {
    console.log(a + b);
});
obj.fire('test', 1, 2); // prints 3 to the console

Parameters

nameStringName of the event to bind the callback to
callbackpc.callbacks.HandleEventFunction that is called when event is fired. Note the callback is limited to 8 arguments.
scopeObjectObject to use as 'this' when the event is fired, defaults to current this

Returns

pc.EventHandler Self for chaining.

once(name, callback, [scope])

Attach an event handler to an event. This handler will be removed after being fired once.

obj.once('test', function (a, b) {
    console.log(a + b);
});
obj.fire('test', 1, 2); // prints 3 to the console
obj.fire('test', 1, 2); // not going to get handled

Parameters

nameStringName of the event to bind the callback to
callbackpc.callbacks.HandleEventFunction that is called when event is fired. Note the callback is limited to 8 arguments.
scopeObjectObject to use as 'this' when the event is fired, defaults to current this

Returns

pc.EventHandler Self for chaining.