Home News About Download

Main Page Widgets Data Structures Related Pages Index

Support Contribute Contact Tracker

Ewl_Callback: The Callback Mechanisms

---

Detailed Description

Defines methods for creating and modifying callbacks on widgets

Tutorial

Data Structures
struct	Ewl_Callback
	Contains information about a callback. More...
struct	Ewl_Callback_Custom
	Contains information about custom callbacks. More...
Defines
#define	EWL_CALLBACK(callback)   ((Ewl_Callback *) callback)
#define	EWL_CALLBACK_CUSTOM(cb)   ((Ewl_Callback_Custom *)cb)
#define	EWL_CALLBACK_FLAG_INTERCEPT(w, t)   w->callbacks[EWL_CALLBACK_INDEX(t)].mask |= EWL_CALLBACK_NOTIFY_INTERCEPT
#define	EWL_CALLBACK_FLAG_NOINTERCEPT(w, t)
#define	EWL_CALLBACK_FLAG_NONOTIFY(w, t)   w->callbacks[EWL_CALLBACK_INDEX(t)].mask &= ~EWL_CALLBACK_NOTIFY_NOTIFY
#define	EWL_CALLBACK_FLAG_NOTIFY(w, t)   w->callbacks[EWL_CALLBACK_INDEX(t)].mask |= EWL_CALLBACK_NOTIFY_NOTIFY
#define	EWL_CALLBACK_FLAGS(w, t)   (w->callbacks[EWL_CALLBACK_INDEX(t)].mask)
#define	EWL_CALLBACK_FUNCTION(cb_func)   ((Ewl_Callback_Function) cb_func)
#define	EWL_CALLBACK_INDEX(t)   ((t < EWL_CALLBACK_MAX) ? t : EWL_CALLBACK_MAX)
#define	EWL_CALLBACK_LEN(w, t)   (w->callbacks[EWL_CALLBACK_INDEX(t)].len)
#define	EWL_CALLBACK_LIST(w, t)   (w->callbacks[EWL_CALLBACK_INDEX(t)].list)
#define	EWL_CALLBACK_NOTIFY_MASK   (0x3)
#define	EWL_CALLBACK_POS(w, t)   w->callbacks[EWL_CALLBACK_INDEX(t)].index
#define	EWL_CALLBACK_SET_DIRECT(w, t)   w->callbacks[EWL_CALLBACK_INDEX(t)].mask |= EWL_CALLBACK_TYPE_DIRECT
#define	EWL_CALLBACK_SET_NODIRECT(w, t)   w->callbacks[EWL_CALLBACK_INDEX(t)].mask &= ~EWL_CALLBACK_TYPE_DIRECT
Typedefs
typedef Ewl_Callback	Ewl_Callback
typedef Ewl_Callback_Custom	Ewl_Callback_Custom
typedef void(*)	Ewl_Callback_Function (Ewl_Widget *widget, void *ev_data, void *user_data)
Functions
Ewl_Callback *	ewl_callback_append (Ewl_Widget *widget, unsigned int type, Ewl_Callback_Function func, void *user_data)
	Append a callback of the specified type.
void	ewl_callback_call (Ewl_Widget *widget, unsigned int type)
	Execute callbacks of specified types for the widget.
void	ewl_callback_call_with_event_data (Ewl_Widget *widget, unsigned int type, void *event_data)
	Execute callbacks with event data.
void	ewl_callback_clear (Ewl_Widget *widget)
void	ewl_callback_del (Ewl_Widget *w, unsigned int t, Ewl_Callback_Function f)
	Delete the specified callback function from the widget.
void	ewl_callback_del_callback (Ewl_Widget *w, unsigned int t, Ewl_Callback *cb)
void	ewl_callback_del_type (Ewl_Widget *w, unsigned int t)
void	ewl_callback_del_with_data (Ewl_Widget *w, unsigned int t, Ewl_Callback_Function f, void *data)
	Delete the specified callback function from the widget.
Ewl_Callback *	ewl_callback_insert_after (Ewl_Widget *w, unsigned int t, Ewl_Callback_Function f, void *user_data, Ewl_Callback_Function after, void *after_data)
	Add a callback after a previous callback in list.
Ewl_Callback *	ewl_callback_prepend (Ewl_Widget *widget, unsigned int type, Ewl_Callback_Function func, void *user_data)
	prepend a callback of the specified type
unsigned int	ewl_callback_type_add (void)
	Creates and returns a new callback identifier.
int	ewl_callbacks_init (void)
	Setup internal registration variables for callbacks.
void	ewl_callbacks_shutdown (void)
	Destroy internal registration variables for callbacks.

---

Define Documentation

#define EWL_CALLBACK

(

callback

)

((Ewl_Callback *) callback)

Typecasts a pointer to an Ewl_Callback pointer.

#define EWL_CALLBACK_CUSTOM

(

cb

)

((Ewl_Callback_Custom *)cb)

Typecasts a pointer to an Ewl_Callback_Custom pointer.

#define EWL_CALLBACK_FLAG_INTERCEPT	(	w,
		t		)	w->callbacks[EWL_CALLBACK_INDEX(t)].mask |= EWL_CALLBACK_NOTIFY_INTERCEPT

Sets the callback intercept flag from a widget for a certain event type.

#define EWL_CALLBACK_FLAG_NOINTERCEPT	(	w,
		t		)

Value:

w->callbacks[EWL_CALLBACK_INDEX(t)].mask = \
                        w->callbacks[EWL_CALLBACK_INDEX(t)].mask & ~EWL_CALLBACK_NOTIFY_INTERCEPT

Clears the callback intercept flag from a widget for a certain event type.

#define EWL_CALLBACK_FLAG_NONOTIFY	(	w,
		t		)	w->callbacks[EWL_CALLBACK_INDEX(t)].mask &= ~EWL_CALLBACK_NOTIFY_NOTIFY

Remove the callback notify flag from a widget for a certain event type.

#define EWL_CALLBACK_FLAG_NOTIFY	(	w,
		t		)	w->callbacks[EWL_CALLBACK_INDEX(t)].mask |= EWL_CALLBACK_NOTIFY_NOTIFY

Sets the callback notify flag from a widget for a certain event type.

#define EWL_CALLBACK_FLAGS	(	w,
		t		)	(w->callbacks[EWL_CALLBACK_INDEX(t)].mask)

Retrives the callback flags from a widget for a certain event type.

#define EWL_CALLBACK_FUNCTION

(

cb_func

)

((Ewl_Callback_Function) cb_func)

Typecasts a pointer to an Ewl_Callback_Function pointer.

#define EWL_CALLBACK_INDEX

(

t

)

((t < EWL_CALLBACK_MAX) ? t : EWL_CALLBACK_MAX)

Retrieves the actual array index for t

#define EWL_CALLBACK_LEN	(	w,
		t		)	(w->callbacks[EWL_CALLBACK_INDEX(t)].len)

Retrives the length from a widget for a certain event type.

#define EWL_CALLBACK_LIST	(	w,
		t		)	(w->callbacks[EWL_CALLBACK_INDEX(t)].list)

Retrives the callback list from a widget for a certain event type.

#define EWL_CALLBACK_NOTIFY_MASK   (0x3)

The value to binary AND with the callback pointer to check the notifiers.

#define EWL_CALLBACK_POS	(	w,
		t		)	w->callbacks[EWL_CALLBACK_INDEX(t)].index

Retrives the current callback position from a widget for an event type.

#define EWL_CALLBACK_SET_DIRECT	(	w,
		t		)	w->callbacks[EWL_CALLBACK_INDEX(t)].mask |= EWL_CALLBACK_TYPE_DIRECT

Sets the callback direct flag for a centain event type

#define EWL_CALLBACK_SET_NODIRECT	(	w,
		t		)	w->callbacks[EWL_CALLBACK_INDEX(t)].mask &= ~EWL_CALLBACK_TYPE_DIRECT

Clears the callback direct flag from a widget for a certain event type

---

Typedef Documentation

typedef struct Ewl_Callback Ewl_Callback

The callbacks used internally for tracking event actions.

typedef struct Ewl_Callback_Custom Ewl_Callback_Custom

The custom callbacks for extended events

typedef void(*) Ewl_Callback_Function(Ewl_Widget *widget, void *ev_data, void *user_data)

A shortcut for declaring functions that take a callback funciton pointer.

---

Function Documentation

Ewl_Callback* ewl_callback_append	(	Ewl_Widget *	w,
		unsigned int	t,
		Ewl_Callback_Function	f,
		void *	user_data
	)

Append a callback of the specified type.

Parameters:

	w,:	the widget to attach the callback
	t,:	the type of the callback that is being attached
	f,:	the function to attach as a callback
	user_data,:	the data to be passed to the callback function

Returns:

Returns NULL on failure, a pointer to the new callback on success.

Allocates a new callback for the specified widget that calls f with user_data as the data parameter when event ta occurs. This event is placed at the end of the callback chain.

Note:

Use the returned callback pointer only for ewl_callback_del_callback().

void ewl_callback_call	(	Ewl_Widget *	w,
		unsigned int	t
	)

Execute callbacks of specified types for the widget.

Parameters:

	w,:	the widget to execute the callbacks
	t,:	the type of the callbacks to be executed

Returns:

Returns no value.

Executes the callback chain for the specified widget w, with event t.

void ewl_callback_call_with_event_data	(	Ewl_Widget *	w,
		unsigned int	t,
		void *	ev_data
	)

Execute callbacks with event data.

Parameters:

	w,:	the widget to execute the callbacks
	t,:	the type of the callbacks to be executed
	ev_data,:	the event data to pass to the callbacks

Returns:

Returns no value.

Similar to ewl_callback_call, but the event data is substituted by ev_data.

void ewl_callback_clear

(

Ewl_Widget *

widget

)

void ewl_callback_del	(	Ewl_Widget *	w,
		unsigned int	t,
		Ewl_Callback_Function	f
	)

Delete the specified callback function from the widget.

Parameters:

	w,:	the widget to delete the callback
	t,:	the type of event associated with the callback
	f,:	the function called by the callback

Returns:

Returns no value. Delete and frees the callback that calls function f when event t occurs to widget w.

void ewl_callback_del_callback	(	Ewl_Widget *	w,
		unsigned int	t,
		Ewl_Callback *	cb
	)

void ewl_callback_del_type	(	Ewl_Widget *	w,
		unsigned int	t
	)

void ewl_callback_del_with_data	(	Ewl_Widget *	w,
		unsigned int	t,
		Ewl_Callback_Function	f,
		void *	d
	)

Delete the specified callback function from the widget.

Parameters:

	w,:	the widget to delete the callback
	t,:	the type of event associated with the callback
	f,:	the function called by the callback
	d,:	the data passed to the callback

Returns:

Returns no value. Delete and frees the callback that calls function f when event t occurs to widget w.

Ewl_Callback* ewl_callback_insert_after	(	Ewl_Widget *	w,
		unsigned int	t,
		Ewl_Callback_Function	f,
		void *	user_data,
		Ewl_Callback_Function	after,
		void *	after_data
	)

Add a callback after a previous callback in list.

Parameters:

	w,:	the widget to insert the callback
	t,:	the type of the callback that is being attached
	f,:	the function to attach as a callback
	user_data,:	the data to be passed to the callback function
	after,:	the function of the callback to append after
	after_data,:	the user data of the callback to append after

Returns:

Returns 0 on failure, the id of the new callback on success.

Same functionality as ewl_callback_append, but the callback is placed after the specified callback on the callback chain.

Ewl_Callback* ewl_callback_prepend	(	Ewl_Widget *	w,
		unsigned int	t,
		Ewl_Callback_Function	f,
		void *	user_data
	)

prepend a callback of the specified type

Parameters:

	w,:	the widget to attach the callback
	t,:	the type of the callback that is being attached
	f,:	the function to attach as a callback
	user_data,:	the data to be passed to the callback function

Returns:

Returns 0 on failure, the pointer to the new callback on success.

Same functionality as ewl_callback_append, but the callback is placed at the beginning of the callback chain.

unsigned int ewl_callback_type_add

(

void

)

Creates and returns a new callback identifier.

Returns:

Returns a new callback identifier

int ewl_callbacks_init

(

void

)

Setup internal registration variables for callbacks.

Returns:

Returns no value.

Sets up some important variables for tracking callbacks that allow shared callbacks.

W/o shared callbacks ewl_test with all windows open has a top line of: 21279 ningerso 19 0 22972 22M 9412 R 6.0 8.0 0:40 ewl_test With shared callbacks ewl_test with all windows open has a top line of: 15901 ningerso 10 0 20120 19M 9148 S 0.0 7.0 0:34 ewl_test

So using shared callbacks saves us over 2 MB of memory in this case.

Ecore_list as the callback storage with all tests open has a top line of: 9121 dsinclai 15 0 71156 17m 4276 S 0.0 1.8 0:11.06 ewl_test Using an array as the callback storage with all tests open has a top line of: 21727 dsinclai 15 0 68360 15m 4304 S 0.0 1.5 0:09.73 ewl_test

So using an array for the callbacks saves us about 2MB of memory in this case.

void ewl_callbacks_shutdown

(

void

)

Destroy internal registration variables for callbacks.

Returns:

Returns no value.

Destroys some important variables for tracking callbacks that allow shared callbacks.

---

Copyright © Enlightenment.org

Enlightened Widget Library Documentation Generated: Sun Sep 27 01:49:46 2009