Module: Battery

Defined in:
ext/accessibility/extras/extras.c,
ext/accessibility/extras/extras.c

Overview

Utility methods for getting information about the system battery (if present).

Instance Method Summary collapse

Instance Method Details

#level ⇒ Float Also known as: charge_level

Returns the batteries charge level as a percentage from 0 to 1

A special value of -1.0 is returned when there is no battery present.

Returns:

  • (Float) 


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# File 'ext/accessibility/extras/extras.c', line 565

static
VALUE
rb_battery_level(VALUE self)
{
  // constant global strings (like ruby symbols, or lisp atoms, NXAtom, etc)
  // so we do not need to release it later (unless you really want to)
  CFStringRef capacity_key     = CFSTR(kIOPSCurrentCapacityKey);
  CFStringRef max_capacity_key = CFSTR(kIOPSMaxCapacityKey);

  double         level = -1.0;
  CFDictionaryRef info = battery_info();

  if (info) {
    CFNumberRef current_cap = CFDictionaryGetValue(info, capacity_key);
    CFNumberRef     max_cap = CFDictionaryGetValue(info, max_capacity_key);

    if (current_cap && max_cap) {
      int current = 0;
      int     max = 0;

      CFNumberGetValue(current_cap, kCFNumberIntType, &current);
      CFNumberGetValue(max_cap,     kCFNumberIntType, &max);

      level = ((double)current)/((double)max);
    }

    CFRelease(info);
  }

  return DBL2NUM(level);
}

#state ⇒ Symbol

Returns the current battery state

The state will be one of:

  • :not_installed
  • :charged
  • :charging
  • :discharging

Returns:

  • (Symbol) 


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# File 'ext/accessibility/extras/extras.c', line 532

static
VALUE
rb_battery_state(VALUE self)
{
  // constant global strings (like ruby symbols, or lisp atoms, NXAtom, etc)
  // so we do not need to release it later (unless you really want to)
  CFStringRef charged_key  = CFSTR(kIOPSIsChargedKey);
  CFStringRef charging_key = CFSTR(kIOPSIsChargingKey);

  VALUE              state = battery_not_installed;
  CFDictionaryRef     info = battery_info();

  if (info) {
    if (CFDictionaryGetValue(info, charged_key) == kCFBooleanTrue)
      state = battery_charged;
    else if (CFDictionaryGetValue(info, charging_key) == kCFBooleanTrue)
      state = battery_charging;
    else
      state = battery_discharging;

    CFRelease(info);
  }

  return state;
}

#time_to_charged ⇒ Fixnum Also known as: time_to_full_charge

Returns the estimated number of minutes until the battery is fully charged

A special value of -1 indicates that the value is currently being estimated and you should try again later.

Returns:

  • (Fixnum) 


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# File 'ext/accessibility/extras/extras.c', line 641

static
VALUE
rb_battery_time_full_charge(VALUE self)
{
  CFStringRef ttfull_key = CFSTR(kIOPSTimeToFullChargeKey);
  int                time = -1;
  CFDictionaryRef    info = battery_info();

  if (info) {
    CFNumberRef current_time = CFDictionaryGetValue(info, ttfull_key);
    if (current_time)
      CFNumberGetValue(current_time, kCFNumberIntType, &time);

    CFRelease(info);
  }

  return INT2FIX(time);
}

#time_to_discharged ⇒ Fixnum Also known as: time_to_empty

Returns the estimated number of minutes until the battery is fully discharged

A special value of -1 indicates that the value is currently being estimated and you should try again later.

A special value of 0 indicates that the battery is not discharging, which usually means that the battery does not exist or is in a charging/charged state.

Returns:

  • (Fixnum) 


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# File 'ext/accessibility/extras/extras.c', line 610

static
VALUE
rb_battery_time_to_empty(VALUE self)
{
  CFStringRef ttempty_key = CFSTR(kIOPSTimeToEmptyKey);
  int                time = -1;
  CFDictionaryRef    info = battery_info();

  if (info) {
    CFNumberRef current_time = CFDictionaryGetValue(info, ttempty_key);
    if (current_time)
      CFNumberGetValue(current_time, kCFNumberIntType, &time);

    CFRelease(info);
  }

  if (time)
    return INT2FIX(time);
  else
    return INT2FIX(0);
}