Control Class

Inheritance diagram of Control

class Control(name, raw_name=None)

Single value input provided by a device.

A control’s value can be queried when the device is open. Event handlers can be attached to the control to be called when the value changes.

The min and max properties are provided as advertised by the device; in some cases the control’s value will be outside this range.

Variables:
  • name – Name of the control, or None if unknown
  • raw_name – Unmodified name of the control, as presented by the operating system; or None if unknown.
  • inverted – If True, the value reported is actually inverted from what the device reported; usually this is to provide consistency across operating systems.

Constructor:

__init__(name, raw_name=None)

Methods:

dispatch_event(event_type, *args) Dispatch a single event to the attached handlers.
event(*args) Function decorator for an event handler.
pop_handlers() Pop the top level of event handlers off the stack.
push_handlers(*args, **kwargs) Push a level onto the top of the handler stack, then attach zero or more event handlers.
register_event_type(name) Register an event type with the dispatcher.
remove_handler(name, handler) Remove a single event handler.
remove_handlers(*args, **kwargs) Remove event handlers from the event stack.
set_handler(name, handler) Attach a single event handler.
set_handlers(*args, **kwargs) Attach one or more event handlers to the top level of the handler stack.

Events:

on_change(value) The value changed.

Attributes:

event_types Type: list
value Current value of the control.

Events

Control.on_change(value)

The value changed.

Parameters:value (float) – Current value of the control.

Attributes

Control.event_types = ['on_change', 'on_press', 'on_release']
Control.value

Current value of the control.

The range of the value is device-dependent; for absolute controls the range is given by min and max (however the value may exceed this range); for relative controls the range is undefined.

Type:float

Inherited members

Methods

Control.dispatch_event(event_type, *args)

Dispatch a single event to the attached handlers.

The event is propagated to all handlers from from the top of the stack until one returns EVENT_HANDLED. This method should be used only by EventDispatcher implementors; applications should call the dispatch_events method.

Since pyglet 1.2, the method returns EVENT_HANDLED if an event handler returned EVENT_HANDLED or EVENT_UNHANDLED if all events returned EVENT_UNHANDLED. If no matching event handlers are in the stack, False is returned.

Parameters:
  • event_type (str) – Name of the event.
  • args (sequence) – Arguments to pass to the event handler.
Return type:

bool or None

Returns:

(Since pyglet 1.2) EVENT_HANDLED if an event handler returned EVENT_HANDLED; EVENT_UNHANDLED if one or more event handlers were invoked but returned only EVENT_UNHANDLED; otherwise False. In pyglet 1.1 and earler, the return value is always None.

Control.event(*args)

Function decorator for an event handler.

Usage:

win = window.Window()

@win.event
def on_resize(self, width, height):
    # ...

or:

@win.event('on_resize')
def foo(self, width, height):
    # ...
Control.pop_handlers()

Pop the top level of event handlers off the stack.

Control.push_handlers(*args, **kwargs)

Push a level onto the top of the handler stack, then attach zero or more event handlers.

If keyword arguments are given, they name the event type to attach. Otherwise, a callable’s __name__ attribute will be used. Any other object may also be specified, in which case it will be searched for callables with event names.

classmethod Control.register_event_type(name)

Register an event type with the dispatcher.

Registering event types allows the dispatcher to validate event handler names as they are attached, and to search attached objects for suitable handlers.

Parameters:name (str) – Name of the event to register.
Control.remove_handler(name, handler)

Remove a single event handler.

The given event handler is removed from the first handler stack frame it appears in. The handler must be the exact same callable as passed to set_handler, set_handlers or push_handlers; and the name must match the event type it is bound to.

No error is raised if the event handler is not set.

Parameters:
  • name (str) – Name of the event type to remove.
  • handler (callable) – Event handler to remove.
Control.remove_handlers(*args, **kwargs)

Remove event handlers from the event stack.

See push_handlers for the accepted argument types. All handlers are removed from the first stack frame that contains any of the given handlers. No error is raised if any handler does not appear in that frame, or if no stack frame contains any of the given handlers.

If the stack frame is empty after removing the handlers, it is removed from the stack. Note that this interferes with the expected symmetry of push_handlers and pop_handlers.

Control.set_handler(name, handler)

Attach a single event handler.

Parameters:
  • name (str) – Name of the event type to attach to.
  • handler (callable) – Event handler to attach.
Control.set_handlers(*args, **kwargs)

Attach one or more event handlers to the top level of the handler stack.

See push_handlers for the accepted argument types.

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