A box is a convenience smart object that packs children inside it in sequence, using a layouting function specified by the user. There are a couple of pre-made layouting functions built-in in Evas, all of them using children size hints to define their size and alignment inside their cell space.

Examples on this smart object's usage:

See also:: Size Hints

Functions
void	evas_object_box_smart_set (Evas_Object_Box_Api *api)
const Evas_Object_Box_Api *	evas_object_box_smart_class_get (void)
Typedefs
typedef struct _Evas_Object_Box_Api	Evas_Object_Box_Api
typedef struct _Evas_Object_Box_Data	Evas_Object_Box_Data
typedef struct _Evas_Object_Box_Option	Evas_Object_Box_Option
typedef void(*	Evas_Object_Box_Layout )(Evas_Object o, Evas_Object_Box_Data priv, void *user_data)
Defines
#define	EVAS_OBJECT_BOX_API_VERSION 1
#define	EVAS_OBJECT_BOX_API_INIT(smart_class_init) {smart_class_init, EVAS_OBJECT_BOX_API_VERSION, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
#define	EVAS_OBJECT_BOX_API_INIT_NULL EVAS_OBJECT_BOX_API_INIT(EVAS_SMART_CLASS_INIT_NULL)
#define	EVAS_OBJECT_BOX_API_INIT_VERSION EVAS_OBJECT_BOX_API_INIT(EVAS_SMART_CLASS_INIT_VERSION)
#define	EVAS_OBJECT_BOX_API_INIT_NAME_VERSION(name) EVAS_OBJECT_BOX_API_INIT(EVAS_SMART_CLASS_INIT_NAME_VERSION(name))

Define Documentation

#define EVAS_OBJECT_BOX_API_INIT ( smart_class_init ) {smart_class_init, EVAS_OBJECT_BOX_API_VERSION, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL}

Initializer for a whole Evas_Object_Box_Api structure, with NULL values on its specific fields.

Parameters:

smart_class_init initializer to use for the "base" field (Evas_Smart_Class).

See also:: EVAS_SMART_CLASS_INIT_NULL; EVAS_SMART_CLASS_INIT_VERSION; EVAS_SMART_CLASS_INIT_NAME_VERSION; EVAS_OBJECT_BOX_API_INIT_NULL; EVAS_OBJECT_BOX_API_INIT_VERSION; EVAS_OBJECT_BOX_API_INIT_NAME_VERSION

#define EVAS_OBJECT_BOX_API_INIT_NAME_VERSION ( name ) EVAS_OBJECT_BOX_API_INIT(EVAS_SMART_CLASS_INIT_NAME_VERSION(name))

Initialize to zero out a whole Evas_Object_Box_Api structure and set its name and version.

This is similar to EVAS_OBJECT_BOX_API_INIT_NULL, but it will also set the version field of Evas_Smart_Class (base field) to the latest EVAS_SMART_CLASS_VERSION and name it to the specific value.

It will keep a reference to the name field as a "const char *", i.e., the name must be available while the structure is used (hint: static or global variable!) and must not be modified.

See also:: EVAS_OBJECT_BOX_API_INIT_NULL; EVAS_OBJECT_BOX_API_INIT_VERSION; EVAS_OBJECT_BOX_API_INIT

#define EVAS_OBJECT_BOX_API_INIT_NULL EVAS_OBJECT_BOX_API_INIT(EVAS_SMART_CLASS_INIT_NULL)

Initialize to zero out a whole Evas_Object_Box_Api structure.

See also:: EVAS_OBJECT_BOX_API_INIT_VERSION; EVAS_OBJECT_BOX_API_INIT_NAME_VERSION; EVAS_OBJECT_BOX_API_INIT

#define EVAS_OBJECT_BOX_API_INIT_VERSION EVAS_OBJECT_BOX_API_INIT(EVAS_SMART_CLASS_INIT_VERSION)

Initialize to zero out a whole Evas_Object_Box_Api structure and set a specific version on it.

This is similar to EVAS_OBJECT_BOX_API_INIT_NULL, but it will set the version field of Evas_Smart_Class (base field) to the latest EVAS_SMART_CLASS_VERSION.

See also:: EVAS_OBJECT_BOX_API_INIT_NULL; EVAS_OBJECT_BOX_API_INIT_NAME_VERSION; EVAS_OBJECT_BOX_API_INIT

#define EVAS_OBJECT_BOX_API_VERSION 1

Current version for Evas box object smart class, a value that goes to _Evas_Object_Box_Api::version.

Typedef Documentation

Evas_Object_Box_Api

Smart class extension, providing extra box object requirements.

Evas_Object_Box_Data

Smart object instance data, providing box object requirements.

Evas_Object_Box_Layout

Function signature for an Evas box object layouting routine. By o it will be passed the box object in question, by priv it will be passed the box's internal data and, by user_data, it will be passed any custom data one could have set to a given box layouting function, with evas_object_box_layout_set().

Examples:: box_example_02.c.

Evas_Object_Box_Option

The base structure for a box option. Box options are a way of extending box items properties, which will be taken into account for layouting decisions. The box layouting functions provided by Evas will only rely on objects' canonical size hints to layout them, so the basic box option has no (custom) property set.

Users creating their own layouts, but not depending on extra child items' properties, would be fine just using evas_object_box_layout_set(). But if one desires a layout depending on extra child properties, he/she has to subclass the box smart object. Thus, by using evas_object_box_smart_class_get() and evas_object_box_smart_set(), the option_new() and option_free() smart class functions should be properly redefined/extended.

Object properties are bound to an integer identifier and must have a name string. Their values are open to any data. See the API on option properties for more details.

Function Documentation

Evas_Object* evas_object_box_add ( Evas * evas )

Add a new box object on the provided canvas.

Parameters:

evas	The canvas to create the box object on.

Returns:: NULL on error, a pointer to a new box object on success.

After instantiation, if a box object hasn't its layout function set, via evas_object_box_layout_set(), it will have it by default set to evas_object_box_layout_horizontal(). The remaining properties of the box must be set/retrieved via evas_object_box_{h,v}_{align,padding}_{get,set)().

Since :: 2.3

Examples:: evas-box.c, and evas-hints.c.

Eina_List* evas_object_box_children_get ( const Evas_Object * o )

Get the list of children objects in a given box object.

Parameters:

o	The box to retrieve an items list from

Returns:: A list of o's child objects, on success, or NULL, on errors (or if it has no child objects)

The returned list should be freed with eina_list_free() when you no longer need it.

Note:: This is a duplicate of the list kept by the box internally. It's up to the user to destroy it when it no longer needs it. It's possible to remove objects from the box when walking this list, but these removals won't be reflected on it.

Since :: 2.3

Examples:: evas-box.c.

Eina_Bool evas_object_box_option_property_get	(	const Evas_Object *	o,
		Evas_Object_Box_Option *	opt,
		int	property,
			...
	)

Get a property's value (by its given numerical identifier), on a given box child element

Parameters:

o	The box parenting the child element
opt	The box option structure bound to the child box element to get a property from
property	The numerical ID of the given property
...	(List of) pointer(s) where to store the value(s) set for this property. It (they) must point to variable(s) of the same type the user has defined for it (them).

Returns:: EINA_TRUE on success, EINA_FALSE on failure.

Note:: This call won't do anything for a canonical Evas box. Only users which have subclassed it, getting custom box items options (see Evas_Object_Box_Option) on it, would benefit from this function. They'd have to implement it and get it to be the _Evas_Object_Box_Api::property_get smart class function of the box, which is originally get to NULL.; This function will internally create a variable argument list, with the values passed after property, and call evas_object_box_option_property_vget() with this list and the same previous arguments.

Since :: 2.3

Eina_Bool evas_object_box_option_property_set	(	Evas_Object *	o,
		Evas_Object_Box_Option *	opt,
		int	property,
			...
	)

Set a property value (by its given numerical identifier), on a given box child element

Parameters:

o	The box parenting the child element
opt	The box option structure bound to the child box element to set a property on
property	The numerical ID of the given property
...	(List of) actual value(s) to be set for this property. It (they) must be of the same type the user has defined for it (them).

Returns:: EINA_TRUE on success, EINA_FALSE on failure.

Note:: This call won't do anything for a canonical Evas box. Only users which have subclassed it, setting custom box items options (see Evas_Object_Box_Option) on it, would benefit from this function. They'd have to implement it and set it to be the _Evas_Object_Box_Api::property_set smart class function of the box, which is originally set to NULL.; This function will internally create a variable argument list, with the values passed after property, and call evas_object_box_option_property_vset() with this list and the same previous arguments.

Since :: 2.3

Eina_Bool evas_object_box_option_property_vget	(	const Evas_Object *	o,
		Evas_Object_Box_Option *	opt,
		int	property,
		va_list	args
	)

Get a property's value (by its given numerical identifier), on a given box child element -- by a variable argument list

Parameters:

o	The box parenting the child element
opt	The box option structure bound to the child box element to get a property from
property	The numerical ID of the given property
args	The variable argument list with pointers to where to store the values of this property. They must point to variables of the same type the user has defined for them.

Returns:: EINA_TRUE on success, EINA_FALSE on failure.

This is a variable argument list variant of the evas_object_box_option_property_get(). See its documentation for more details.

Since :: 2.3

Eina_Bool evas_object_box_option_property_vset	(	Evas_Object *	o,
		Evas_Object_Box_Option *	opt,
		int	property,
		va_list	args
	)

Set a property value (by its given numerical identifier), on a given box child element -- by a variable argument list

Parameters:

o	The box parenting the child element
opt	The box option structure bound to the child box element to set a property on
property	The numerical ID of the given property
args	The variable argument list implementing the value to be set for this property. It must be of the same type the user has defined for it.

Returns:: EINA_TRUE on success, EINA_FALSE on failure.

This is a variable argument list variant of the evas_object_box_option_property_set(). See its documentation for more details.

Since :: 2.3

const Evas_Object_Box_Api* evas_object_box_smart_class_get ( void )

Get the Evas box smart class, for inheritance purposes.

Returns:: the (canonical) Evas box smart class.

The returned value is not to be modified, just use it as your parent class. 2.3

void evas_object_box_smart_set ( Evas_Object_Box_Api * api )

Set the default box api struct (Evas_Object_Box_Api) with the default values. May be used to extend that API.

Parameters:

api	The box API struct to set back, most probably with overridden fields (on class extensions scenarios) 2.3

Functions

Typedefs

Defines

Define Documentation

Typedef Documentation

Function Documentation