Slider
PUBLISHED
The slider UI component is a draggable item used to select a value within a certain range. For more information, see the Slider [1] API.
This feature is supported in wearable applications only.
Basic Usage
To use a slider component in your application:
- Create a new slider with the
elm_slider_add()
function:Evas_Object *slider = NULL; slider = elm_slider_add(parent);
- Configure the slider. The following configurations are optional. Unless you set other options, the slider uses the default styles.
- Set the slider indicator:
elm_slider_indicator_show_set(slider, EINA_TRUE); elm_slider_indicator_format_set(slider, "%.0f");
- Set the range and value of the slider:
elm_slider_min_max_set(slider, 0.0, 10.0); elm_slider_value_set(slider, 5.0);
-
The slider for wearable devices does not support additional features, such as horizontal or inverted slider.
- Set the slider indicator:
- Register the callback functions.
The following example shows how to define and register a callback for the
changed
signal:evas_object_smart_callback_add(slider, "changed", slider_changed_cb, NULL); void slider_changed_cb(void *data, Evas_Object *obj, void *event_info) { double _val = elm_slider_value_get(obj); dlog_print(DLOG_INFO, LOG_TAG, "Slider value changed. %0.1f\n", _val); }
The following example shows a simple use case of the slider component.
Example: Slider use case
|
Evas_Object *box; Evas_Object *slider; Evas_Object *nf; /* Starting right after the basic EFL UI layout code [2] */ /* (win - conformant - naviframe) */ box = elm_box_add(nf); elm_naviframe_item_push(nf, "Slider", NULL, NULL, box, NULL); /* Add a slider */ slider = elm_slider_add(box); evas_object_size_hint_align_set(slider, EVAS_HINT_FILL, 0.5); /* Indicator shows the value of the slider */ elm_slider_indicator_show_set(slider, EINA_TRUE); elm_slider_indicator_format_set(slider, "%.0f"); /* Set the slider range */ elm_slider_min_max_set(slider, 0.0, 10.0); /* Show the slider */ evas_object_show(slider); elm_box_pack_end(box, slider); |
Styles
The following table lists the available component styles.
Table: Slider styles
Style | Sample |
---|---|
default |
Callbacks
You can register callback functions connected to the following signals for a slider object.
Table: Slider callback signals
Signal | Description | event_info |
---|---|---|
changed |
The slider value is changed by the user. | NULL |
delay,changed |
A short time after the value is changed by the user. This is called only when the user stops dragging for a very short period or when they release their finger or mouse, so it avoids possibly expensive reactions to the value change. | NULL |
slider,drag,start |
Dragging the slider indicator around has started. | NULL |
slider,drag,stop |
Dragging the slider indicator around has stopped. | NULL |