efl/legacy/elementary/src/lib/elm_slider.c

#include <Elementary.h>
#include "elm_priv.h"

/**
 * @defgroup Slider Slider
 *
 * The slider adds a dragable “slider” widget for selecting the value of
 * something within a range.
 *
 * Signals that you can add callbacks for are:
 *
 * changed - Whenever the slider value is changed by the user.
 *
 * delay,changed - A short time after the value is changed by the user.
 * This will be called only when the user stops dragging for a very short
 * period or when they release their finger/mouse, so it avoids possibly
 * expensive reactions to the value change.
 *
 * slider,drag,start - dragging the slider indicator around has started
 *
 * slider,drag,stop - dragging the slider indicator around has stopped
 *
 * A slider can be horizontal or vertical. It can contain an Icon and has a
 * primary label as well as a units label (that is formatted with floating
 * point values and thus accepts a printf-style format string, like
 * “%1.2f units”. There is also an indicator string that may be somewhere
 * else (like on the slider itself) that also accepts a format string like
 * units. Label, Icon Unit and Indicator strings/objects are optional.
 *
 * A slider may be inverted which means values invert, with high vales being
 * on the left or top and low values on the right or bottom (as opposed to
 * normally being low on the left or top and high on the bottom and right).
 *
 * The slider should have its minimum and maximum values set by the
 * application with  elm_slider_min_max_set() and value should also be set by
 * the application before use with  elm_slider_value_set(). The span of the
 * slider is its length (horizontally or vertically). This will be scaled by
 * the object or applications scaling factor. At any point code can query the
 * slider for its value with elm_slider_value_get().
 */

typedef struct _Widget_Data Widget_Data;

struct _Widget_Data
{
   Evas_Object *slider;
   Evas_Object *icon;
   Evas_Object *spacer;
   const char *label;
   const char *units;
   const char *indicator;
   const char *(*indicator_format_func)(double val);
   Eina_Bool horizontal : 1;
   Eina_Bool inverted : 1;
   double val, val_min, val_max;
   Ecore_Timer *delay;
   Evas_Coord size;
};

static const char *widtype = NULL;
static void _del_hook(Evas_Object *obj);
static void _theme_hook(Evas_Object *obj);
static void _sizing_eval(Evas_Object *obj);
static void _changed_size_hints(void *data, Evas *e, Evas_Object *obj, void *event_info);
static void _sub_del(void *data, Evas_Object *obj, void *event_info);
static void _units_set(Evas_Object *obj);
static void _indicator_set(Evas_Object *obj);

static void
_del_hook(Evas_Object *obj)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if (wd->label) eina_stringshare_del(wd->label);
   if (wd->indicator) eina_stringshare_del(wd->units);
   if (wd->delay) ecore_timer_del(wd->delay);
   free(wd);
}

static void
_theme_hook(Evas_Object *obj)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if (wd->horizontal)
     _elm_theme_set(wd->slider, "slider", "horizontal", elm_widget_style_get(obj));
   else
     _elm_theme_set(wd->slider, "slider", "vertical", elm_widget_style_get(obj));
   if (wd->inverted)
     edje_object_signal_emit(wd->slider, "elm,state,inverted,on", "elm");
   else
     edje_object_signal_emit(wd->slider, "elm,state,inverted,off", "elm");
   if (wd->icon)
     edje_object_signal_emit(wd->slider, "elm,state,icon,visible", "elm");
   else
     edje_object_signal_emit(wd->slider, "elm,state,icon,hidden", "elm");
   if (wd->label)
     edje_object_signal_emit(wd->slider, "elm,state,text,visible", "elm");
   else
     edje_object_signal_emit(wd->slider, "elm,state,text,hidden", "elm");
   edje_object_part_text_set(wd->slider, "elm.text", wd->label);
   if (wd->units)
     edje_object_signal_emit(wd->slider, "elm,state,units,visible", "elm");
   else
     edje_object_signal_emit(wd->slider, "elm,state,units,hidden", "elm");
   if (wd->horizontal)
     evas_object_size_hint_min_set(wd->spacer, (double)wd->size * elm_widget_scale_get(obj) * _elm_config->scale, 1);
   else
     evas_object_size_hint_min_set(wd->spacer, 1, (double)wd->size * elm_widget_scale_get(obj) * _elm_config->scale);
   edje_object_part_swallow(wd->slider, "elm.swallow.bar", wd->spacer);
   _units_set(obj);
   edje_object_message_signal_process(wd->slider);
   edje_object_scale_set(wd->slider, elm_widget_scale_get(obj) * _elm_config->scale);
   _sizing_eval(obj);
}

static void
_sizing_eval(Evas_Object *obj)
{   
   Widget_Data *wd = elm_widget_data_get(obj);
   Evas_Coord minw = -1, minh = -1, maxw = -1, maxh = -1;
   if (!wd) return;
   elm_coords_finger_size_adjust(1, &minw, 1, &minh);
   edje_object_size_min_restricted_calc(wd->slider, &minw, &minh, minw, minh);
   elm_coords_finger_size_adjust(1, &minw, 1, &minh);
   evas_object_size_hint_min_set(obj, minw, minh);
   evas_object_size_hint_max_set(obj, maxw, maxh);
}

static void
_changed_size_hints(void *data, Evas *e __UNUSED__, Evas_Object *obj, void *event_info __UNUSED__)
{
   Widget_Data *wd = elm_widget_data_get(data);
   if (!wd) return;
   if (obj != wd->icon) return;
   _sizing_eval(data);
}

static void
_sub_del(void *data __UNUSED__, Evas_Object *obj, void *event_info)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   Evas_Object *sub = event_info;
   if (!wd) return;
   if (sub == wd->icon)
     {
	edje_object_signal_emit(wd->slider, "elm,state,icon,hidden", "elm");
	evas_object_event_callback_del_full
	  (sub, EVAS_CALLBACK_CHANGED_SIZE_HINTS, _changed_size_hints, obj);
	wd->icon = NULL;
	_sizing_eval(obj);
     }
}

static int
_delay_change(void *data)
{
   Widget_Data *wd = elm_widget_data_get(data);
   if (!wd) return 0;
   wd->delay = NULL;
   evas_object_smart_callback_call(data, "delay,changed", NULL);
   return 0;
}

static void
_val_fetch(Evas_Object *obj)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   double posx = 0.0, posy = 0.0, pos = 0.0, val;
   if (!wd) return;
   edje_object_part_drag_value_get(wd->slider, "elm.dragable.slider",
				   &posx, &posy);
   if (wd->horizontal) pos = posx;
   else pos = posy;
   if (wd->inverted) pos = 1.0 - pos;
   val = (pos * (wd->val_max - wd->val_min)) + wd->val_min;
   if (val != wd->val)
     {
	wd->val = val;
	evas_object_smart_callback_call(obj, "changed", NULL);
	if (wd->delay) ecore_timer_del(wd->delay);
	wd->delay = ecore_timer_add(0.2, _delay_change, obj);
     }
}

static void
_val_set(Evas_Object *obj)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   double pos;
   if (!wd) return;
   if (wd->val_max > wd->val_min)
     pos = (wd->val - wd->val_min) / (wd->val_max - wd->val_min);
   else
     pos = 0.0;
   if (pos < 0.0) pos = 0.0;
   else if (pos > 1.0) pos = 1.0;
   if (wd->inverted) pos = 1.0 - pos;
   edje_object_part_drag_value_set(wd->slider, "elm.dragable.slider", pos, pos);
}

static void
_units_set(Evas_Object *obj)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if (wd->units)
     {
	char buf[1024];

	snprintf(buf, sizeof(buf), wd->units, wd->val);
	edje_object_part_text_set(wd->slider, "elm.units", buf);
     }
   else
     edje_object_part_text_set(wd->slider, "elm.units", NULL);
}

static void
_indicator_set(Evas_Object *obj)
{
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if (wd->indicator_format_func)
     {
	const char *buf;
	buf = wd->indicator_format_func(wd->val);
	edje_object_part_text_set(wd->slider, "elm.indicator", buf);
     }
   else if (wd->indicator)
     {
	char buf[1024];
	snprintf(buf, sizeof(buf), wd->indicator, wd->val);
	edje_object_part_text_set(wd->slider, "elm.indicator", buf);
     }
   else
     edje_object_part_text_set(wd->slider, "elm.indicator", NULL);
}

static void
_drag(void *data, Evas_Object *obj __UNUSED__, const char *emission __UNUSED__, const char *source __UNUSED__)
{
   _val_fetch(data);
   _units_set(data);
   _indicator_set(data);
}

static void
_drag_start(void *data, Evas_Object *obj __UNUSED__, const char *emission __UNUSED__, const char *source __UNUSED__)
{
   _val_fetch(data);
   evas_object_smart_callback_call(data, "slider,drag,start", NULL);
   _units_set(data);
   _indicator_set(data);
}

static void
_drag_stop(void *data, Evas_Object *obj __UNUSED__, const char *emission __UNUSED__, const char *source __UNUSED__)
{
   _val_fetch(data);
   evas_object_smart_callback_call(data, "slider,drag,stop", NULL);
   _units_set(data);
   _indicator_set(data);
}

/**
 * Add a new slider to the parent
 *
 * @param parent The parent object
 * @return The new object or NULL if it cannot be created
 *
 * @ingroup Slider
 */
EAPI Evas_Object *
elm_slider_add(Evas_Object *parent)
{
   Evas_Object *obj;
   Evas *e;
   Widget_Data *wd;

   wd = ELM_NEW(Widget_Data);
   e = evas_object_evas_get(parent);
   obj = elm_widget_add(e);
   ELM_SET_WIDTYPE(widtype, "slider");
   elm_widget_type_set(obj, "slider");
   elm_widget_sub_object_add(parent, obj);
   elm_widget_data_set(obj, wd);
   elm_widget_del_hook_set(obj, _del_hook);
   elm_widget_theme_hook_set(obj, _theme_hook);

   wd->horizontal = EINA_TRUE;
   wd->val = 0.0;
   wd->val_min = 0.0;
   wd->val_max = 1.0;

   wd->slider = edje_object_add(e);
   _elm_theme_set(wd->slider, "slider", "horizontal", "default");
   elm_widget_resize_object_set(obj, wd->slider);
   edje_object_signal_callback_add(wd->slider, "drag", "*", _drag, obj);
   edje_object_signal_callback_add(wd->slider, "drag,start", "*", _drag_start, obj);
   edje_object_signal_callback_add(wd->slider, "drag,stop", "*", _drag_stop, obj);
   edje_object_signal_callback_add(wd->slider, "drag,step", "*", _drag_stop, obj);
   edje_object_signal_callback_add(wd->slider, "drag,page", "*", _drag_stop, obj);
//   edje_object_signal_callback_add(wd->slider, "drag,set", "*", _drag_stop, obj);
   edje_object_part_drag_value_set(wd->slider, "elm.dragable.slider", 0.0, 0.0);

   wd->spacer = evas_object_rectangle_add(e);
   evas_object_color_set(wd->spacer, 0, 0, 0, 0);
   evas_object_pass_events_set(wd->spacer, 1);
   elm_widget_sub_object_add(obj, wd->spacer);
   edje_object_part_swallow(wd->slider, "elm.swallow.bar", wd->spacer);

   evas_object_smart_callback_add(obj, "sub-object-del", _sub_del, obj);

   _sizing_eval(obj);
   return obj;
}

/**
 * Set the label of the slider
 *
 * @param obj The slider object
 * @param label The text label string in UTF-8
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_label_set(Evas_Object *obj, const char *label)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   eina_stringshare_replace(&wd->label, label);
   if (label)
     {
	edje_object_signal_emit(wd->slider, "elm,state,text,visible", "elm");
	edje_object_message_signal_process(wd->slider);
     }
   else
     {
	edje_object_signal_emit(wd->slider, "elm,state,text,hidden", "elm");
	edje_object_message_signal_process(wd->slider);
     }
   edje_object_part_text_set(wd->slider, "elm.text", label);
   _sizing_eval(obj);
}

/**
 * Get the label of the slider
 *
 * @param obj The slider object
 * @return The text label string in UTF-8
 *
 * @ingroup Slider
 */
EAPI const char *
elm_slider_label_get(const Evas_Object *obj)
{
   ELM_CHECK_WIDTYPE(obj, widtype) NULL;
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return NULL;
   return wd->label;
}

/**
 * Set the icon object of the slider object
 *
 * Once the icon object is set, it will become a child of the slider object and
 * be deleted when the slider object is deleted. If another icon object is set
 * then the previous one becomes orophaned and will no longer be deleted along
 * with the slider.
 *
 * @param obj The slider object
 * @param icon The icon object
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_icon_set(Evas_Object *obj, Evas_Object *icon)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if ((wd->icon != icon) && (wd->icon))
     elm_widget_sub_object_del(obj, wd->icon);
   wd->icon = icon;
   if (icon)
     {
	elm_widget_sub_object_add(obj, icon);
	evas_object_event_callback_add(icon, EVAS_CALLBACK_CHANGED_SIZE_HINTS,
				       _changed_size_hints, obj);
	edje_object_part_swallow(wd->slider, "elm.swallow.content", icon);
	edje_object_signal_emit(wd->slider, "elm,state,icon,visible", "elm");
	_sizing_eval(obj);
     }
}

/**
 * Get the icon object of the slider object
 *
 * @param obj The slider object
 * @return The icon object
 *
 * @ingroup Slider
 */
EAPI Evas_Object *
elm_slider_icon_get(const Evas_Object *obj)
{
   ELM_CHECK_WIDTYPE(obj, widtype) NULL;
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return NULL;
   return wd->icon;
}

/**
 * Set the length of the dragable region of the slider
 *
 * Thois sets the minimum width or height (depending on orientation) of the
 * area of the slider that allows the slider to be dragged around. This in
 * turn affects the objects minimum size (along with icon label and unit
 * text). Note that this will also get multiplied by the scale factor.
 *
 * @param obj The slider object
 * @param size The length of the slider area
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_span_size_set(Evas_Object *obj, Evas_Coord size)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if (wd->size == size) return;
   wd->size = size;
   if (wd->horizontal)
     evas_object_size_hint_min_set(wd->spacer, (double)wd->size * elm_widget_scale_get(obj) * _elm_config->scale, 1);
   else
     evas_object_size_hint_min_set(wd->spacer, 1, (double)wd->size * elm_widget_scale_get(obj) * _elm_config->scale);
   edje_object_part_swallow(wd->slider, "elm.swallow.bar", wd->spacer);
   _sizing_eval(obj);
}

/**
 * Set the format string of the unit area
 *
 * If NULL, this disabls the unit area display. If not it sets the format
 * string for the unit text. The unit text is provided a floating point
 * value, so the unit text can display up to 1 floating point value. Note that
 * this is optional. Use a format string such as "%1.2f meters" for example.
 *
 * @param obj The slider object
 * @param units The format string for the units display
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_unit_format_set(Evas_Object *obj, const char *units)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   eina_stringshare_replace(&wd->units, units);
   if (units)
     {
	edje_object_signal_emit(wd->slider, "elm,state,units,visible", "elm");
	edje_object_message_signal_process(wd->slider);
     }
   else
     {
	edje_object_signal_emit(wd->slider, "elm,state,units,hidden", "elm");
	edje_object_message_signal_process(wd->slider);
     }
   _units_set(obj);
   _sizing_eval(obj);
}

/**
 * Set the format string for the inducator area
 *
 * The slider may also display a value (the value of the slider) somewhere
 * (for example above the slider knob that is dragged around). This sets the
 * format string for this. See elm_slider_unit_format_set() for more
 * information on how this works.
 *
 * @param obj The slider object
 * @param indicator The format string for the indicator display
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_indicator_format_set(Evas_Object *obj, const char *indicator)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   eina_stringshare_replace(&wd->indicator, indicator);
   _indicator_set(obj);
}

/**
 * Set orientation of the slider
 *
 * @param obj The slider object
 * @param horizontal If set, the slider will be horizontal
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_horizontal_set(Evas_Object *obj, Eina_Bool horizontal)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   horizontal = !!horizontal;
   if (wd->horizontal == horizontal) return;
   wd->horizontal = horizontal;
   _theme_hook(obj);
}

/**
 * Set the minimum and maximum values for the slider
 *
 * Maximum mut be greater than minimum.
 *
 * @param obj The slider object
 * @param min The minimum value
 * @param max The maximum value
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_min_max_set(Evas_Object *obj, double min, double max)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if ((wd->val_min == min) && (wd->val_max == max)) return;
   wd->val_min = min;
   wd->val_max = max;
   if (wd->val < wd->val_min) wd->val = wd->val_min;
   if (wd->val > wd->val_max) wd->val = wd->val_max;
   _val_set(obj);
   _units_set(obj);
   _indicator_set(obj);
}

/**
 * Set the value the slider indicates
 *
 * @param obj The slider object
 * @param val The value (must be beween min and max for the slider)
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_value_set(Evas_Object *obj, double val)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   if (wd->val == val) return;
   wd->val = val;
   if (wd->val < wd->val_min) wd->val = wd->val_min;
   if (wd->val > wd->val_max) wd->val = wd->val_max;
   _val_set(obj);
   _units_set(obj);
   _indicator_set(obj);
}

/**
 * Get the value the slider has
 *
 * @param obj The slider object
 * @return The value of the slider
 *
 * @ingroup Slider
 */
EAPI double
elm_slider_value_get(const Evas_Object *obj)
{
   ELM_CHECK_WIDTYPE(obj, widtype) 0.0;
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return 0.0;
   return wd->val;
}

/**
 * Invert the slider display
 *
 * Normally the slider will display and interpret values from low to high
 * and when horizontal that is left to right. When vertical that is top
 * to bottom. This inverts this (so from right to left or bottom to top) if
 * inverted is set to 1.
 *
 * @param obj The slider object
 * @param inverted The inverted flag. 1 == inverted, 0 == normal
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_inverted_set(Evas_Object *obj, Eina_Bool inverted)
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   inverted = !!inverted;
   if (wd->inverted == inverted) return;
   wd->inverted = inverted;
   if (wd->inverted)
     edje_object_signal_emit(wd->slider, "elm,state,inverted,on", "elm");
   else
     edje_object_signal_emit(wd->slider, "elm,state,inverted,off", "elm");
   edje_object_message_signal_process(wd->slider);
   _val_set(obj);
   _units_set(obj);
   _indicator_set(obj);
}

/**
 * Set the format function pointer for the inducator area
 *
 * Set the callback function to format the indicator string.
 * See elm_slider_indicator_format_set() for more info on how this works.
 *
 * @param obj The slider object
 * @param indicator The format string for the indicator display
 * @param func The indicator format function
 *
 * @ingroup Slider
 */
EAPI void
elm_slider_indicator_format_function_set(Evas_Object *obj, const char *(*func)(double val))
{
   ELM_CHECK_WIDTYPE(obj, widtype);
   Widget_Data *wd = elm_widget_data_get(obj);
   if (!wd) return;
   wd->indicator_format_func = func;
   _indicator_set(obj);
}