ScrollbarComponent(system, entity) 

Create a new ScrollbarComponent.

Parameters

system	ScrollbarComponentSystem	The ComponentSystem that created this Component.
entity	Entity	The Entity that this Component is attached to.

EntityhandleEntity 

The entity to be used as the scrollbar handle. This entity must have a Scrollbar component.

numberhandleSize 

The size of the handle relative to the size of the track, in the range 0 to 1. For a vertical scrollbar, a value of 1 means that the handle will take up the full height of the track.

numberorientation 

Whether the scrollbar moves horizontally or vertically. Can be:

• ORIENTATION_HORIZONTAL: The scrollbar animates in the horizontal axis.
• ORIENTATION_VERTICAL: The scrollbar animates in the vertical axis.

Defaults to ORIENTATION_HORIZONTAL.

numbervalue 

The current position value of the scrollbar, in the range 0 to 1. Defaults to 0.

set:value 

Fired whenever the scroll value changes.

Parameters

value

number

The current scroll value.

booleanenabled 

Enables or disables the component.

Entityentity 

The Entity that this Component is attached to.

ComponentSystemsystem 

The ComponentSystem used to create this Component.

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

name	string	Name 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

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

name

string

The 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.

const 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 handler functions, called 'test' with scope this

Parameters

name	string	Name of the event to unbind.
callback	HandleEventCallback	Function to be unbound.
scope	object	Scope that was used as the this when the event is fired.

Returns

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

const evt = obj.on('test', function (a, b) {
    console.log(a + b);
});
// some time later
evt.off();

Parameters

name	string	Name of the event to bind the callback to.
callback	HandleEventCallback	Function that is called when event is fired. Note the callback is limited to 8 arguments.
scope	object	Object to use as 'this' when the event is fired, defaults to current this.

Returns

EventHandle

Can be used for removing event in the future.

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

name	string	Name of the event to bind the callback to.
callback	HandleEventCallback	Function that is called when event is fired. Note the callback is limited to 8 arguments.
scope	object	Object to use as 'this' when the event is fired, defaults to current this.

Returns

EventHandle

• can be used for removing event in the future.