Tizen Native API  5.5
Background

Background object, used for setting a solid color, image or Edje group as a background to a window or any container object.

bg_inheritance_tree.png
preview-00.png

The bg (background) widget is used for setting (solid) background decorations to a window (unless it has transparency enabled) or to any container object. It works just like an image, but has some properties useful to a background, like setting it to tiled, centered, scaled or stretched.

This widget inherits from the Layout one, so that all the functions acting on it also work for background objects.

Default content parts of the bg widget that you can use for are:

  • "overlay" - overlay of the bg

Here is some sample code using it:

Functions

Evas_Objectelm_bg_add (Evas_Object *parent)
 Adds a new background to the parent.
void elm_bg_color_set (Evas_Object *obj, int r, int g, int b)
 Sets the color on a given background widget.
void elm_bg_color_get (const Evas_Object *obj, int *r, int *g, int *b)
 Gets the color set on a given background widget.
Eina_Bool elm_bg_file_set (Eo *obj, const char *file, const char *group)
 Sets the file (image or edje collection) to give life for the background.
void elm_bg_file_get (const Eo *obj, const char **file, const char **group)
 Gets the file (image or edje collection) set on a given background widget.
void elm_bg_option_set (Evas_Object *obj, Elm_Bg_Option option)
 Sets the mode of display for a given background widget's image.
Elm_Bg_Option elm_bg_option_get (const Evas_Object *obj)
 Gets the mode of display of a given background widget's image.
void elm_bg_load_size_set (Evas_Object *obj, int w, int h)
 Sets the size of the pixmap representation of the image set on a given background widget.

Enumeration Type Documentation

Identifiers on how a background widget is to display its image.

-- if it was set to use an image file.

Enumerator:
ELM_BG_OPTION_CENTER 

Center the background image.

ELM_BG_OPTION_SCALE 

Scale the background image, retaining aspect ratio (default).

ELM_BG_OPTION_STRETCH 

Stretch the background image to fill the widget's area.

ELM_BG_OPTION_TILE 

Tile background image at its original size.

ELM_BG_OPTION_LAST 

Sentinel value to indicate last enum field during iteration. Also used to indicate errors


Function Documentation

Adds a new background to the parent.

Parameters:
parentThe parent object
Returns:
The new object or NULL if it cannot be created
Since :
2.3
Examples:
bg_example_02.c, bg_example_03.c, combobox_example_01.c, gengrid_example.c, index_example_02.c, and transit_example_03.c.
void elm_bg_color_get ( const Evas_Object obj,
int *  r,
int *  g,
int *  b 
)

Gets the color set on a given background widget.

Parameters:
objThe background object handle
rWhere to store the red color component's value
gWhere to store the green color component's value
bWhere to store the blue color component's value
Note:
Use NULL pointers on the file components you're not interested in: they'll be ignored by the function.
See also:
elm_bg_color_get() for more details
Since :
2.3
void elm_bg_color_set ( Evas_Object obj,
int  r,
int  g,
int  b 
)

Sets the color on a given background widget.

Parameters:
objThe background object handle
rThe red color component's value
gThe green color component's value
bThe blue color component's value

This sets the color used for the background rectangle, in RGB format. Each color component's range is from 0 to 255.

Note:
You probably only want to use this function if you haven't previously called elm_bg_file_set(), so that you just want a solid color background.
You can reset the color by setting r, g, b as -1, -1, -1.
See also:
elm_bg_color_get()
Since :
2.3
Examples:
bg_example_03.c.
void elm_bg_file_get ( const Eo *  obj,
const char **  file,
const char **  group 
)

Gets the file (image or edje collection) set on a given background widget.

Note:
Use NULL pointers on the file components you're not interested in: they'll be ignored by the function.
Parameters:
[in]objThe background object handle
[out]fileThe file path
[out]groupOptional key (group in Edje) within the file
Since :
2.3
Eina_Bool elm_bg_file_set ( Eo *  obj,
const char *  file,
const char *  group 
)

Sets the file (image or edje collection) to give life for the background.

Returns:
EINA_TRUE on success, EINA_FALSE otherwise

This sets the image file used in the background object. If the image comes from an Edje group, it will be stretched to completely fill the background object. If it comes from a traditional image file, it will by default be centered in this widget's area (thus retaining its aspect), what could lead to some parts being not visible. You may change the mode of exhibition for a real image file with elm_bg_option_set().

Note:
Once the image of obj is set, a previously set one will be deleted, even if file is NULL.
This will only affect the contents of one of the background's swallow spots, namely "elm.swallow.background". If you want to achieve the Layout's file setting behavior, you'll have to call that method on this object.
Parameters:
[in]objThe background object handle
[in]fileThe file path
[in]groupOptional key (group in Edje) within the file
Since :
2.3
Examples:
bg_example_02.c, bg_example_03.c, gengrid_example.c, and index_example_02.c.
void elm_bg_load_size_set ( Evas_Object obj,
int  w,
int  h 
)

Sets the size of the pixmap representation of the image set on a given background widget.

Warning:
: This function just makes sense if an image file was set on obj, with elm_bg_file_set().

This function sets a new size for pixmap representation of the given bg image. It allows for the image to be loaded already in the specified size, reducing the memory usage and load time (for example, when loading a big image file with its load size set to a smaller size)

Note:
: This is just a hint for the underlying system. The real size of the pixmap may differ depending on the type of image being loaded, being bigger than requested.
Parameters:
[in]wThe new width of the image pixmap representation
[in]hThe new height of the image pixmap representation
Since :
2.3
Examples:
bg_example_02.c.

Gets the mode of display of a given background widget's image.

Returns:
The background option Elm.Bg.Option Default is #Elm_Bg_SCALE.
See also:
elm_bg_option_set()
Since :
2.3
void elm_bg_option_set ( Evas_Object obj,
Elm_Bg_Option  option 
)

Sets the mode of display for a given background widget's image.

This sets how the background widget will display its image. This will only work if the elm_bg_file_set() was previously called with an image file on $obj. The image can be display tiled, scaled, centered or stretched. ELM_BG_OPTION_SCALE by default.

Parameters:
[in]optionThe desired background option(See Elm.Bg.Option).
See also:
elm_bg_option_get()
Since :
2.3
Examples:
bg_example_02.c, and bg_example_03.c.