Evas_Object_Box_Group(3)

NAME
Evas_Object_Box_Group - Box Smart Object

 - A box is a convenience smart object that packs children inside it in sequence, using a layouting function specified by the user.

SYNOPSIS

  Data Structures
struct _Evas_Object_Box_Api
This structure should be used by any smart class inheriting from the box's one, to provide custom box behavior that could not be achieved only by providing a layout function, with evas_object_box_layout_set().
struct _Evas_Object_Box_Data
This structure augments clipped smart object's instance data, providing extra members required by generic box implementation.
struct _Evas_Object_Box_Option
Evas_Object_Box_Option struct fields

  Macros
#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.
#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.
#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.
#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.
#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.

  Typedefs
typedef struct _Evas_Object_Box_Api Evas_Object_Box_Api
Smart class extension, providing extra box object requirements.
typedef struct _Evas_Object_Box_Data Evas_Object_Box_Data
Smart object instance data, providing box object requirements.
typedef struct _Evas_Object_Box_Option Evas_Object_Box_Option
The base structure for a box option.
typedef void(* Evas_Object_Box_Layout) (Evas_Object *o, Evas_Object_Box_Data *priv, void *user_data)
Function signature for an Evas box object layouting routine.

  Functions
EVAS_API void evas_object_box_align_set (Evas_Box *obj, double horizontal, double vertical)
Set the alignment of the whole bounding box of contents, for a given box object.
EVAS_API void evas_object_box_align_get (const Evas_Box *obj, double *horizontal, double *vertical)
Get the alignment of the whole bounding box of contents, for a given box object.
EVAS_API void evas_object_box_padding_set (Evas_Box *obj, int horizontal, int vertical)
Set the (space) padding between cells set for a given box object.
EVAS_API void evas_object_box_padding_get (const Evas_Box *obj, int *horizontal, int *vertical)
Get the (space) padding between cells set for a given box object.
EVAS_API void evas_object_box_layout_set (Evas_Box *obj, Evas_Object_Box_Layout cb, const void *data, Eina_Free_Cb free_data)
Set a new layouting function to a given box object.
EVAS_API void evas_object_box_layout_horizontal (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a (basic) horizontal box.
EVAS_API void evas_object_box_layout_vertical (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a (basic) vertical box.
EVAS_API void evas_object_box_layout_homogeneous_max_size_horizontal (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a maximum size, homogeneous horizontal box.
EVAS_API void evas_object_box_layout_flow_vertical (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a flow vertical box.
EVAS_API Evas_Object_Box_Option * evas_object_box_insert_after (Evas_Box *obj, Efl_Canvas_Object *child, const Efl_Canvas_Object *reference)
Insert a new child object after another existing one, in a given box object o.
EVAS_API Eina_Bool evas_object_box_remove_all (Evas_Box *obj, Eina_Bool clear)
Remove all child objects from a box object, unparenting them again.
EVAS_API Eina_Iterator * evas_object_box_iterator_new (const Evas_Box *obj)
Get an iterator to walk the list of children of a given box object.
EVAS_API Efl_Canvas_Object * evas_object_box_add_to (Evas_Box *obj)
Add a new box as a child of a given smart object.
EVAS_API Evas_Object_Box_Option * evas_object_box_append (Evas_Box *obj, Efl_Canvas_Object *child)
Append a new child object to the given box object o.
EVAS_API int evas_object_box_option_property_id_get (const Evas_Box *obj, const char *name)
Get the numerical identifier of the property of the child elements of the box o which have name as name string.
EVAS_API Evas_Object_Box_Option * evas_object_box_prepend (Evas_Box *obj, Efl_Canvas_Object *child)
Prepend a new child object to the given box object o.
EVAS_API Eina_Accessor * evas_object_box_accessor_new (const Evas_Box *obj)
Get an accessor (a structure providing random items access) to the list of children of a given box object.
EVAS_API Eina_Bool evas_object_box_remove_at (Evas_Box *obj, unsigned int pos)
Remove an object, bound to a given position in a box object, unparenting it again.
EVAS_API Evas_Object_Box_Option * evas_object_box_insert_before (Evas_Box *obj, Efl_Canvas_Object *child, const Efl_Canvas_Object *reference)
Insert a new child object before another existing one, in a given box object o.
EVAS_API const char * evas_object_box_option_property_name_get (const Evas_Box *obj, int property)
Get the name of the property of the child elements of the box o which have id as identifier.
EVAS_API void evas_object_box_layout_homogeneous_horizontal (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a homogeneous horizontal box.
EVAS_API void evas_object_box_layout_homogeneous_max_size_vertical (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a maximum size, homogeneous vertical box.
EVAS_API Evas_Object_Box_Option * evas_object_box_insert_at (Evas_Box *obj, Efl_Canvas_Object *child, unsigned int pos)
Insert a new child object at a given position, in a given box object o.
EVAS_API Eina_Bool evas_object_box_remove (Evas_Box *obj, Efl_Canvas_Object *child)
Remove a given object from a box object, unparenting it again.
EVAS_API void evas_object_box_layout_stack (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a stacking box.
EVAS_API void evas_object_box_layout_homogeneous_vertical (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a homogeneous vertical box.
EVAS_API void evas_object_box_layout_flow_horizontal (Evas_Box *obj, Evas_Object_Box_Data *priv, void *data)
Layout function which sets the box o to a flow horizontal box.
EVAS_API 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.
EVAS_API const Evas_Object_Box_Api * evas_object_box_smart_class_get (void)
Get the Evas box smart class, for inheritance purposes.
EVAS_API Evas_Object * evas_object_box_add (Evas *evas)
Add a new box object on the provided canvas.
EVAS_API 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.
EVAS_API 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.
EVAS_API 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.
EVAS_API 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.
EVAS_API Eina_List * evas_object_box_children_get (const Evas_Object *o)
Get the list of children objects in a given box object.

Detailed Description

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:

•   Evas box example

•   Evas alignment, minimum size, maximum size, padding and weight hints example

See also
    Size Hints

Macro Definition 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_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_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

Typedef Documentation

  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.

  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.

Function Documentation

  EVAS_API void evas_object_box_align_set (Evas_Box * obj, double horizontal, double vertical)

Set the alignment of the whole bounding box of contents, for a given box object. This will influence how a box object is to align its bounding box of contents within its own area. The values must be in the range $0.0 - $1.0, or undefined behavior is expected. For horizontal alignment, $0.0 means to the left, with $1.0 meaning to the right. For vertical alignment, $0.0 means to the top, with $1.0 meaning to the bottom.

Note
    The default values for both alignments is $0.5.

See also evas_object_box_align_get.

Parameters
    obj The object.
    horizontal The horizontal alignment, in pixels.
    vertical The vertical alignment, in pixels.

  EVAS_API void evas_object_box_align_get (const Evas_Box * obj, double * horizontal, double * vertical)

Get the alignment of the whole bounding box of contents, for a given box object. See also evas_object_box_align_set for more information.

Parameters
    obj The object.
    horizontal The horizontal alignment, in pixels.
    vertical The vertical alignment, in pixels.

  EVAS_API void evas_object_box_padding_set (Evas_Box * obj, int horizontal, int vertical)

Set the (space) padding between cells set for a given box object.

Note
    The default values for both padding components is $0.

See also evas_object_box_padding_get.

Parameters
    obj The object.
    horizontal The horizontal padding, in pixels.
    vertical The vertical padding, in pixels.

  EVAS_API void evas_object_box_padding_get (const Evas_Box * obj, int * horizontal, int * vertical)

Get the (space) padding between cells set for a given box object. See also evas_object_box_padding_set.

Parameters
    obj The object.
    horizontal The horizontal padding, in pixels.
    vertical The vertical padding, in pixels.

  EVAS_API void evas_object_box_layout_set (Evas_Box * obj, Evas_Object_Box_Layout cb, const void * data, Eina_Free_Cb free_data)

Set a new layouting function to a given box object. A box layout function affects how a box object displays child elements within its area. The list of pre-defined box layouts available in Evas are evas_object_box_layout_horizontal, evas_object_box_layout_vertical, evas_object_box_layout_homogeneous_horizontal, evas_object_box_layout_homogeneous_vertical, evas_object_box_layout_homogeneous_max_size_horizontal, evas_object_box_layout_homogeneous_max_size_vertical, evas_object_box_layout_flow_horizontal, evas_object_box_layout_flow_vertical and evas_object_box_layout_stack

Refer to each of their documentation texts for details on them.

Note
    A box layouting function will be triggered by the $'calculate' smart callback of the box's smart class.

Parameters
    obj The object.
    cb The new layout function to set on o.
    data Data pointer to be passed to cb.
    free_data Function to free data, if need be.

Referenced by elm_box_layout_set().

  EVAS_API void evas_object_box_layout_horizontal (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a (basic) horizontal box. In this layout, the box object's overall behavior is controlled by its padding/alignment properties, which are set by the evas_object_box_{h,v}_{align,padding}_set family of functions. The size hints of the elements in the box -- set by the evas_object_size_hint_{align,padding,weight}_set functions -- also control the way this function works.

Box's properties: align_h controls the horizontal alignment of the child objects relative to the containing box. When set to $0.0, children are aligned to the left. A value of $1.0 makes them aligned to the right border. Values in between align them proportionally. Note that if the size required by the children, which is given by their widths and the padding_h property of the box, is bigger than the their container's width, the children will be displayed out of the box's bounds. A negative value of align_h makes the box to justify its children. The padding between them, in this case, is corrected so that the leftmost one touches the left border and the rightmost one touches the right border (even if they must overlap). The align_v and padding_v properties of the box don't contribute to its behaviour when this layout is chosen.

Child element's properties: align_x does not influence the box's behavior. padding_l and padding_r sum up to the container's horizontal padding between elements. The child's padding_t, padding_b and align_y properties apply for padding/alignment relative to the overall height of the box. Finally, there is the weight_x property, which, if set to a non-zero value, tells the container that the child width is not pre-defined. If the container can't accommodate all its children, it sets the widths of the ones with weights to sizes as small as they can all fit into it. If the size required by the children is less than the available, the box increases its childrens' (which have weights) widths as to fit the remaining space. The weight_x property, besides telling the element is resizable, gives a weight for the resizing process. The parent box will try to distribute (or take off) widths accordingly to the normalized list of weights: most weighted children remain/get larger in this process than the least ones. weight_y does not influence the layout.

If one desires that, besides having weights, child elements must be resized bounded to a minimum or maximum size, those size hints must be set, by the evas_object_size_hint_{min,max}_set functions.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API void evas_object_box_layout_vertical (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a (basic) vertical box. This function behaves analogously to evas_object_box_layout_horizontal. The description of its behaviour can be derived from that function's documentation.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API void evas_object_box_layout_homogeneous_max_size_horizontal (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a maximum size, homogeneous horizontal box. In a maximum size, homogeneous horizontal box, besides having cells of equal size reserved for the child objects, this size will be defined by the size of the largest child in the box (in width). The box's overall behavior is controlled by its properties, which are set by the evas_object_box_{h,v}_{align,padding}_set family of functions. The size hints of the elements in the box -- set by the evas_object_size_hint_{align,padding,weight}_set functions -- also control the way this function works.

Box's properties: padding_h tells the box to draw empty spaces of that size, in pixels, between the child objects' cells. align_h controls the horizontal alignment of the child objects, relative to the containing box. When set to $0.0, children are aligned to the left. A value of $1.0 lets them aligned to the right border. Values in between align them proportionally. A negative value of align_h makes the box to justify its children cells. The padding between them, in this case, is corrected so that the leftmost one touches the left border and the rightmost one touches the right border (even if they must overlap). The align_v and padding_v properties of the box don't contribute to its behaviour when this layout is chosen.

Child element's properties: padding_l and padding_r sum up to the required width of the child element. The align_x property tells the relative position of this overall child width in its allocated cell ($0.0 to extreme left, $1.0 to extreme right). A value of $-1.0 to align_x makes the box try to resize this child element to the exact width of its cell (respecting the minimum and maximum size hints on the child's width and accounting for its horizontal padding hints). The child's padding_t, padding_b and align_y properties apply for padding/alignment relative to the overall height of the box. A value of $-1.0 to align_y makes the box try to resize this child element to the exact height of its parent (respecting the max hint on the child's height).

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API void evas_object_box_layout_flow_vertical (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a flow vertical box. This function behaves analogously to evas_object_box_layout_flow_horizontal. The description of its behaviour can be derived from that function's documentation.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API Evas_Object_Box_Option* evas_object_box_insert_after (Evas_Box * obj, Efl_Canvas_Object * child, const Efl_Canvas_Object * reference)

Insert a new child object after another existing one, in a given box object o. On success, the $'child,added' smart event will take place.

Note
    This function will fail if reference is not a member of o.

    The actual placing of the item relative to o's area will depend on the layout set to it.

    This call will trigger the box's _Evas_Object_Box_Api.insert_after smart function.

Parameters
    obj The object.
    child A child Evas object to be made a member of o.
    reference The child object to place this new one after.

Returns
    A box option bound to the recently added box item or null, on errors

  EVAS_API Eina_Bool evas_object_box_remove_all (Evas_Box * obj, Eina_Bool clear)

Remove all child objects from a box object, unparenting them again. This has the same effect of calling evas_object_box_remove on each of o's child objects, in sequence. If, and only if, all those calls succeed, so does this one.

Parameters
    obj The object.
    clear If true, it will delete just removed children.

Returns
    true on success, false otherwise.

  EVAS_API Eina_Iterator* evas_object_box_iterator_new (const Evas_Box * obj)

Get an iterator to walk the list of children of a given box object.

Note
    Do not remove or delete objects while walking the list.

Parameters
    obj The object.

Returns
    An iterator on o's child objects, on success, or null, on errors.

  EVAS_API Efl_Canvas_Object* evas_object_box_add_to (Evas_Box * obj)

Add a new box as a child of a given smart object. This is a helper function that has the same effect of putting a new box object into parent by use of evas_object_smart_member_add.

Parameters
    obj The object.

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

  EVAS_API Evas_Object_Box_Option* evas_object_box_append (Evas_Box * obj, Efl_Canvas_Object * child)

Append a new child object to the given box object o. On success, the $'child,added' smart event will take place.

Note
    The actual placing of the item relative to o's area will depend on the layout set to it. For example, on horizontal layouts an item in the end of the box's list of children will appear on its right.

    This call will trigger the box's _Evas_Object_Box_Api.append smart function.

Parameters
    obj The object.
    child A child Evas object to be made a member of o.

Returns
    A box option bound to the recently added box item or null, on errors.

Referenced by elm_win_resize_object_add().

  EVAS_API int evas_object_box_option_property_id_get (const Evas_Box * obj, const char * name)

Get the numerical identifier of the property of the child elements of the box o which have name as name string.

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_id_get smart class function of the box, which is originally set to null.

Parameters
    obj The object.
    name The name string of the option being searched, for its ID.

Returns
    The numerical ID of the given property or $-1, on errors.

  EVAS_API Evas_Object_Box_Option* evas_object_box_prepend (Evas_Box * obj, Efl_Canvas_Object * child)

Prepend a new child object to the given box object o. On success, the $'child,added' smart event will take place.

Note
    The actual placing of the item relative to o's area will depend on the layout set to it. For example, on horizontal layouts an item in the beginning of the box's list of children will appear on its left.

    This call will trigger the box's _Evas_Object_Box_Api.prepend smart function.

Parameters
    obj The object.
    child A child Evas object to be made a member of o.

Returns
    A box option bound to the recently added box item or null, on errors.

  EVAS_API Eina_Accessor* evas_object_box_accessor_new (const Evas_Box * obj)

Get an accessor (a structure providing random items access) to the list of children of a given box object.

Note
    Do not remove or delete objects while walking the list.

Parameters
    obj The object.

Returns
    An accessor on o's child objects, on success, or null, on errors.

  EVAS_API Eina_Bool evas_object_box_remove_at (Evas_Box * obj, unsigned int pos)

Remove an object, bound to a given position in a box object, unparenting it again. On removal, you'll get an unparented object again, just as it was before you inserted it in the box. The option_free box smart callback will be called automatically for you and, also, the $'child,removed' smart event will take place.

Note
    This function will fail if the given position is invalid, given o's internal list of elements.

    This call will trigger the box's _Evas_Object_Box_Api.remove_at smart function.

Parameters
    obj The object.
    pos The numeric position (starting from $0) of the child object to be removed.

Returns
    true on success, false on failure.

  EVAS_API Evas_Object_Box_Option* evas_object_box_insert_before (Evas_Box * obj, Efl_Canvas_Object * child, const Efl_Canvas_Object * reference)

Insert a new child object before another existing one, in a given box object o. On success, the $'child,added' smart event will take place.

Note
    This function will fail if reference is not a member of o.

    The actual placing of the item relative to o's area will depend on the layout set to it.

    This call will trigger the box's _Evas_Object_Box_Api.insert_before smart function.

Parameters
    obj The object.
    child A child Evas object to be made a member of o.
    reference The child object to place this new one before.

Returns
    A box option bound to the recently added box item or null, on errors.

  EVAS_API const char* evas_object_box_option_property_name_get (const Evas_Box * obj, int property)

Get the name of the property of the child elements of the box o which have id as identifier.

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_name_get smart class function of the box, which is originally set to null.

Parameters
    obj The object.
    property The numerical identifier of the option being searched, for its name.

Returns
    The name of the given property or null, on errors.

  EVAS_API void evas_object_box_layout_homogeneous_horizontal (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a homogeneous horizontal box. In a homogeneous horizontal box, its width is divided equally between the contained objects. The box's overall behavior is controlled by its padding/alignment properties, which are set by the evas_object_box_{h,v}_{align,padding}_set family of functions. The size hints the elements in the box -- set by the evas_object_size_hint_{align,padding,weight}_set functions -- also control the way this function works.

Box's properties: align_h has no influence on the box for this layout. padding_h tells the box to draw empty spaces of that size, in pixels, between the (equal) child objects' cells. The align_v and padding_v properties of the box don't contribute to its behaviour when this layout is chosen.

Child element's properties: padding_l and padding_r sum up to the required width of the child element. The align_x property tells the relative position of this overall child width in its allocated cell ($0.0 to extreme left, $1.0 to extreme right). A value of $-1.0 to align_x makes the box try to resize this child element to the exact width of its cell (respecting the minimum and maximum size hints on the child's width and accounting for its horizontal padding hints). The child's padding_t, padding_b and align_y properties apply for padding/alignment relative to the overall height of the box. A value of $-1.0 to align_y makes the box try to resize this child element to the exact height of its parent (respecting the maximum size hint on the child's height).

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API void evas_object_box_layout_homogeneous_max_size_vertical (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a maximum size, homogeneous vertical box. This function behaves analogously to evas_object_box_layout_homogeneous_max_size_horizontal. The description of its behaviour can be derived from that function's documentation.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API Evas_Object_Box_Option* evas_object_box_insert_at (Evas_Box * obj, Efl_Canvas_Object * child, unsigned int pos)

Insert a new child object at a given position, in a given box object o. On success, the $'child,added' smart event will take place.

Note
    This function will fail if the given position is invalid, given o's internal list of elements.

    The actual placing of the item relative to o's area will depend on the layout set to it.

    This call will trigger the box's _Evas_Object_Box_Api.insert_at smart function.

Parameters
    obj The object.
    child A child Evas object to be made a member of o.
    pos The numeric position (starting from $0) to place the new child object at.

Returns
    A box option bound to the recently added box item or null, on errors.

  EVAS_API Eina_Bool evas_object_box_remove (Evas_Box * obj, Efl_Canvas_Object * child)

Remove a given object from a box object, unparenting it again. On removal, you'll get an unparented object again, just as it was before you inserted it in the box. The _Evas_Object_Box_Api.option_free box smart callback will be called automatically for you and, also, the $'child,removed' smart event will take place.

Note
    This call will trigger the box's _Evas_Object_Box_Api.remove smart function.

Parameters
    obj The object.
    child The handle to the child object to be removed.

Returns
    true on success, false otherwise.

Referenced by elm_win_resize_object_del().

  EVAS_API void evas_object_box_layout_stack (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a stacking box. In a stacking box, all children will be given the same size -- the box's own size -- and they will be stacked one above the other, so that the first object in o's internal list of child elements will be the bottommost in the stack.

Box's properties: No box properties are used.

Child element's properties: padding_l and padding_r sum up to the required width of the child element. The align_x property tells the relative position of this overall child width in its allocated cell ($0.0 to extreme left, $1.0 to extreme right). A value of $-1.0 to align_x makes the box try to resize this child element to the exact width of its cell (respecting the min and max hints on the child's width and accounting for its horizontal padding properties). The same applies to the vertical axis.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API void evas_object_box_layout_homogeneous_vertical (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a homogeneous vertical box. This function behaves analogously to evas_object_box_layout_homogeneous_horizontal. The description of its behaviour can be derived from that function's documentation.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API void evas_object_box_layout_flow_horizontal (Evas_Box * obj, Evas_Object_Box_Data * priv, void * data)

Layout function which sets the box o to a flow horizontal box. In a flow horizontal box, the box's child elements are placed in rows (think of text as an analogy). A row has as many elements as can fit into the box's width. The box's overall behavior is controlled by its properties, which are set by the evas_object_box_{h,v}_{align,padding}_set family of functions. The size hints of the elements in the box -- set by the evas_object_size_hint_{align,padding,weight}_set functions -- also control the way this function works.

Box's properties: padding_h tells the box to draw empty spaces of that size, in pixels, between the child objects' cells. align_h dictates the horizontal alignment of the rows ($0.0 to left align them, $1.0 to right align). A value of $-1.0 to align_h lets the rows justified horizontally. align_v controls the vertical alignment of the entire set of rows ($0.0 to top, $1.0 to bottom). A value of $-1.0 to align_v makes the box to justify the rows vertically. The padding between them in this case is corrected so that the first row touches the top border and the last one touches the bottom border (even if they must overlap). padding_v has no influence on the layout.

Child element's properties: padding_l and padding_r sum up to the required width of the child element. The align_x property has no influence on the layout. The child's padding_t and padding_b sum up to the required height of the child element and is the only means (besides row justifying) of setting space between rows. Note, however, that align_y dictates positioning relative to the largest height required by a child object in the actual row.

Parameters
    obj The object.
    priv Private data pointer
    data Data pointer

  EVAS_API 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)

  EVAS_API 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.

  EVAS_API 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)().

References EINA_SAFETY_ON_FALSE_RETURN_VAL, and EVAS_CANVAS_CLASS.

  EVAS_API 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.

Referenced by evas_object_box_option_property_get().

  EVAS_API 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.

Referenced by evas_object_box_option_property_set().

  EVAS_API 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.

References evas_object_box_option_property_vset().

  EVAS_API 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.

References evas_object_box_option_property_vget().

  EVAS_API 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.

References eina_list_append(), EINA_LIST_FOREACH, and _Evas_Object_Box_Option::obj.

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