Module: Tk::Event

Defined in:
lib/ffi-tk/command/event.rb,
lib/ffi-tk/event/data.rb,
lib/ffi-tk/event/handler.rb

Overview

Miscellaneous event facilities: define virtual events and generate events

The event command provides several facilities for dealing with window system events, such as defining virtual events and synthesizing events.

Please note that virtual event means events that are generated inside the application and are written as “<<virtual>>”, where virtual is the name of the event.

Sequences are names for single keys, or key combinations, also various other actions create events, such as <MouseWheel> or <Destroy>. A sequence is written as “<Control-Alt-Delete>”, so only one enclosing <> pair to distinguish them from virtual events.

Defined Under Namespace

Modules: Handler Classes: Data

Class Method Summary collapse

Class Method Details

.add(virtual, *sequences) ⇒ Object

Associates the virtual event virtual with the physical event sequence(s) given by the sequence arguments, so that the virtual event will trigger whenever any one of the sequences occurs. Virtual may be any string value and sequence may have any of the values allowed for the sequence argument to the bind command. If virtual is already defined, the new physical event sequences add to the existing sequences for the event.



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# File 'lib/ffi-tk/command/event.rb', line 23

def self.add(virtual, *sequences)
  Tk.execute_only(:event, :add, virtual, *sequences)
end

.delete(virtual, *sequences) ⇒ Object

Deletes each of the sequences from those associated with the virtual event given by virtual. Virtual may be any string value and sequence may have any of the values allowed for the sequence argument to the bind command. Any sequences not currently associated with virtual are ignored. If no sequence argument is provided, all physical event sequences are removed for virtual, so that the virtual event will not trigger anymore.



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# File 'lib/ffi-tk/command/event.rb', line 34

def self.delete(virtual, *sequences)
  Tk.execute_only(:event, :delete, virtual, *sequences)
end

.generate(window = None, event = None, options = {}) ⇒ Object

Generates a window event and arranges for it to be processed just as if it had come from the window system. window gives the path name of the window for which the event will be generated; it may also be an identifier (such as returned by winfo id) as long as it is for a window in the current application. Event provides a basic description of the event, such as <Shift-Button-2> or <<Paste>>. If window is empty the whole screen is meant, and coordinates are relative to the screen. Event may have any of the forms allowed for the sequence argument of the bind command except that it must consist of a single event pattern, not a sequence.

options may be used to specify additional attributes of the event, such as the x and y mouse position. See the documentation of [EventData] for a comprehensive list.

If the :when option is not specified, the event is processed immediately: all of the handlers for the event will complete before the event generate command returns

If the :when option is specified then it determines when the event is processed. Certain events, such as key events, require that the window has focus to receive the event properly.



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# File 'lib/ffi-tk/command/event.rb', line 62

def self.generate(window = None, event = None, options = {})
  Tk.execute_only(:event, :generate, window, event, options)
end

.info(virtual = None) ⇒ Object

Returns information about virtual events. If the <<virtual>> argument is omitted, the return value is a list of all the virtual events that are currently defined.

If <<virtual>> is specified then the return value is a list whose elements are the physical event sequences currently defined for the given virtual event; if the virtual event is not defined then an empty string is returned. Note that virtual events that that are not bound to physical event sequences are not returned by event info.



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# File 'lib/ffi-tk/command/event.rb', line 75

def self.info(virtual = None)
  Tk.execute(:event, :info, virtual).to_a
end