Tizen Native API  5.5

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A box arranges objects in a linear fashion, governed by a layout function that defines the details of this arrangement.

By default, the box will use an internal function to set the layout to a single row, either vertical or horizontal. This layout is affected by a number of parameters, such as the homogeneous flag set by elm_box_homogeneous_set(), the values given by elm_box_padding_set() and elm_box_align_set() and the hints set to each object in the box.

For this default layout, it's possible to change the orientation with elm_box_horizontal_set(). The box will start in the vertical orientation, placing its elements ordered from top to bottom. When horizontal is set, the order will go from left to right. If the box is set to be homogeneous, every object in it will be assigned the same space, that of the largest object. Padding can be used to set some spacing between the cell given to each object. The alignment of the box, set with elm_box_align_set(), determines how the bounding box of all the elements will be placed within the space given to the box widget itself.

The size hints of each object also affect how they are placed and sized within the box. evas_object_size_hint_min_set() will give the minimum size the object can have, and the box will use it as the basis for all latter calculations. Elementary widgets set their own minimum size as needed, so there's rarely any need to use it manually.

evas_object_size_hint_weight_set(), when not in homogeneous mode, is used to tell whether the object will be allocated the minimum size it needs or if the space given to it should be expanded. It's important to realize that expanding the size given to the object is not the same thing as resizing the object. It could very well end being a small widget floating in a much larger empty space. If not set, the weight for objects will normally be 0.0 for both axis, meaning the widget will not be expanded. To take as much space possible, set the weight to EVAS_HINT_EXPAND (defined to 1.0) for the desired axis to expand.

Besides how much space each object is allocated, it's possible to control how the widget will be placed within that space using evas_object_size_hint_align_set(). By default, this value will be 0.5 for both axis, meaning the object will be centered, but any value from 0.0 (left or top, for the x and y axes, respectively) to 1.0 (right or bottom) can be used. The special value EVAS_HINT_FILL, which is -1.0, means the object will be resized to fill the entire space it was allocated.

In addition, customized functions to define the layout can be set, which allow the application developer to organize the objects within the box in any number of ways.

The special elm_box_layout_transition() function can be used to switch from one layout to another, animating the motion of the children of the box.

Note:
Objects should not be added to box objects using _add() calls.

Some examples on how to use boxes follow:

Functions

void elm_box_layout_transition (Evas_Object *obj, Evas_Object_Box_Data *priv, void *data)
Elm_Box_Transitionelm_box_transition_new (const double duration, Evas_Object_Box_Layout start_layout, void *start_layout_data, Ecore_Cb start_layout_free_data, Evas_Object_Box_Layout end_layout, void *end_layout_data, Ecore_Cb end_layout_free_data, Ecore_Cb transition_end_cb, void *transition_end_data)
void elm_box_transition_free (void *data)
Evas_Objectelm_box_add (Evas_Object *parent)

Typedefs

typedef struct _Elm_Box_Transition Elm_Box_Transition

Typedef Documentation

Opaque handler containing the parameters to perform an animated transition of the layout the box uses.

See also:
elm_box_transition_new()
elm_box_layout_set()
elm_box_layout_transition()

Function Documentation

void elm_box_layout_transition ( Evas_Object obj,
Evas_Object_Box_Data priv,
void *  data 
)

Special layout function that animates the transition from one layout to another

Parameters:
objThe object.
privThe smart object instance data.
dataData will be passed to function.

Normally, when switching the layout function for a box, this will be reflected immediately on screen on the next render, but it's also possible to do this through an animated transition.

This is done by creating an Elm_Box_Transition and setting the box layout to this function.

For example:

 Elm_Box_Transition *t = elm_box_transition_new(1.0,
                            evas_object_box_layout_vertical, // start
                            NULL, // data for initial layout
                            NULL, // free function for initial data
                            evas_object_box_layout_horizontal, // end
                            NULL, // data for final layout
                            NULL, // free function for final data
                            anim_end, // will be called when animation ends
                            NULL); // data for anim_end function
 elm_box_layout_set(box, elm_box_layout_transition, t,
                    elm_box_transition_free);
Note:
This function can only be used with elm_box_layout_set(). Calling it directly will not have the expected results.
See also:
elm_box_transition_new
elm_box_transition_free
elm_box_layout_set
Since :
2.3
Examples:
box_example_02.c.
void elm_box_transition_free ( void *  data)

Free a Elm_Box_Transition instance created with elm_box_transition_new().

This function is mostly useful as the free_data parameter in elm_box_layout_set() when elm_box_layout_transition().

Parameters:
dataThe Elm_Box_Transition instance to be freed.
See also:
elm_box_transition_new
elm_box_layout_transition
Since :
2.3
Examples:
box_example_02.c.
Elm_Box_Transition* elm_box_transition_new ( const double  duration,
Evas_Object_Box_Layout  start_layout,
void *  start_layout_data,
Ecore_Cb  start_layout_free_data,
Evas_Object_Box_Layout  end_layout,
void *  end_layout_data,
Ecore_Cb  end_layout_free_data,
Ecore_Cb  transition_end_cb,
void *  transition_end_data 
)

Create a new Elm_Box_Transition to animate the switch of layouts

If you want to animate the change from one layout to another, you need to set the layout function of the box to elm_box_layout_transition(), passing as user data to it an instance of Elm_Box_Transition with the necessary information to perform this animation. The free function to set for the layout is elm_box_transition_free().

The parameters to create an Elm_Box_Transition sum up to how long will it be, in seconds, a layout function to describe the initial point, another for the final position of the children and one function to be called when the whole animation ends. This last function is useful to set the definitive layout for the box, usually the same as the end layout for the animation, but could be used to start another transition.

Parameters:
durationThe duration of the transition in seconds
start_layoutThe layout function that will be used to start the animation
start_layout_dataThe data to be passed the start_layout function
start_layout_free_dataFunction to free start_layout_data
end_layoutThe layout function that will be used to end the animation
end_layout_dataData param passed to end_layout
end_layout_free_dataThe data to be passed the end_layout function
end_layout_free_dataFunction to free end_layout_data
transition_end_cbCallback function called when animation ends
transition_end_dataData to be passed to transition_end_cb
Returns:
An instance of Elm_Box_Transition
See also:
elm_box_transition_new
elm_box_layout_transition
Since :
2.3
Examples:
box_example_02.c.