This feature is supported in wearable applications only.

The circle scroller component changes corresponding to the rotary events. It shows the whole scrollable area with a circular scroll bar.

The circle scroller wraps the scroller component (elm_scroller) internally to draw a circular scroller to the edge of the circular screen. This means that you can use the elm_scroller callbacks and functions, excluding the elm_scroller_policy_set() and elm_scroller_policy_get() functions.

For more information, see the Efl Extension Circle Scroller API.

Figure: Circle scroller component

Adding a Circle Scroller Component

To create a circle scroller component, use the eext_circle_object_scroller_add() function. Pass a elm_scroller component as the first parameter and a circle surface as the second parameter.

Evas_Object *scroller;
Evas_Object *circle_scroller;

scroller = elm_scroller_add(parent);
circle_scroller = eext_circle_object_scroller_add(scroller, surface);

The circle scroller component is created with the default style.

Configuring the Circle Scroller

You can use the elm_scroller functions to configure a circle scroller, except for the elm_scroller_policy_set() and elm_scroller_policy_get() functions.

To set the circle scroller policy, use the eext_circle_object_scroller_policy_set() function. The scroller policy can be:

• ELM_SCROLLER_POLICY_AUTO: Scrollbar is made visible if it is needed, and otherwise kept hidden.
• ELM_SCROLLER_POLICY_ON: Scrollbar is always visible.
• ELM_SCROLLER_POLICY_OFF: Scrollbar is always hidden.

The following example sets the horizontal scrollbar on when needed and the vertical scrollbar always off:

eext_circle_object_scroller_policy_set(circle_scroller, ELM_SCROLLER_POLICY_AUTO, ELM_SCROLLER_POLICY_OFF);

To get the current scroller policy, use the eext_circle_object_scroller_policy_get() function.

Activating a Rotary Event

To activate or deactivate the circle scroller, use the eext_rotary_object_event_activated_set() function:

eext_rotary_object_event_activated_set(circle_scroller, EINA_TRUE);

If the second parameter is EINA_TRUE, the circle scroller can receive rotary events.

Configuring the Circle Properties

To configure the circle properties of the circle scroller:

• You can modify the circle object within the circle scroller component using the following functions:

  • eext_circle_object_line_width_set()
  • eext_circle_object_line_width_get()
  • eext_circle_object_radius_set()
  • eext_circle_object_radius_get()
  • eext_circle_object_color_set()
  • eext_circle_object_color_get()
  • eext_circle_object_disabled_set()
  • eext_circle_object_disabled_get()

• You can modify the circle scroller item properties with the eext_circle_object_item_XXX() functions.

  The circle scroller has the following items:

  • default: Default circle item that draws the vertical scroller.
  • vertical,scroll,bg: Vertical scroller background circle item.
  • horizontal,scroll,bar: Horizontal scroller circle item.
  • horizontal,scroll,bg: Horizontal scroller background circle item.

For more information, see Circle Object and the Efl Extension Circle Object API.