src/power/uikit/SDL_syspower.m
author Sam Lantinga <slouken@libsdl.org>
Fri, 14 Jun 2019 13:56:42 -0700
changeset 12860 0f52dd40abe5
parent 12503 806492103856
child 13422 fd6a12de91c7
permissions -rw-r--r--
Worked around "Undefined symbol: ___isPlatformVersionAtLeast()" link error on Xcode 11 beta
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 #include "../../SDL_internal.h"
    22 
    23 #ifndef SDL_POWER_DISABLED
    24 #if SDL_POWER_UIKIT
    25 
    26 #import <UIKit/UIKit.h>
    27 
    28 #include "SDL_power.h"
    29 #include "SDL_timer.h"
    30 #include "SDL_assert.h"
    31 #include "SDL_syspower.h"
    32 
    33 #if !TARGET_OS_TV
    34 /* turn off the battery monitor if it's been more than X ms since last check. */
    35 static const int BATTERY_MONITORING_TIMEOUT = 3000;
    36 static Uint32 SDL_UIKitLastPowerInfoQuery = 0;
    37 
    38 void
    39 SDL_UIKit_UpdateBatteryMonitoring(void)
    40 {
    41     if (SDL_UIKitLastPowerInfoQuery) {
    42         if (SDL_TICKS_PASSED(SDL_GetTicks(), SDL_UIKitLastPowerInfoQuery + BATTERY_MONITORING_TIMEOUT)) {
    43             UIDevice *uidev = [UIDevice currentDevice];
    44             SDL_assert([uidev isBatteryMonitoringEnabled] == YES);
    45             [uidev setBatteryMonitoringEnabled:NO];
    46             SDL_UIKitLastPowerInfoQuery = 0;
    47         }
    48     }
    49 }
    50 #else
    51 void
    52 SDL_UIKit_UpdateBatteryMonitoring(void)
    53 {
    54     /* Do nothing. */
    55 }
    56 #endif /* !TARGET_OS_TV */
    57 
    58 SDL_bool
    59 SDL_GetPowerInfo_UIKit(SDL_PowerState * state, int *seconds, int *percent)
    60 {
    61 #if TARGET_OS_TV
    62     *state = SDL_POWERSTATE_NO_BATTERY;
    63     *seconds = -1;
    64     *percent = -1;
    65 #else /* TARGET_OS_TV */
    66     @autoreleasepool {
    67         UIDevice *uidev = [UIDevice currentDevice];
    68 
    69         if (!SDL_UIKitLastPowerInfoQuery) {
    70             SDL_assert(uidev.isBatteryMonitoringEnabled == NO);
    71             uidev.batteryMonitoringEnabled = YES;
    72         }
    73 
    74         /* UIKit_GL_SwapWindow() (etc) will check this and disable the battery
    75          *  monitoring if the app hasn't queried it in the last X seconds.
    76          *  Apparently monitoring the battery burns battery life.  :)
    77          *  Apple's docs say not to monitor the battery unless you need it.
    78          */
    79         SDL_UIKitLastPowerInfoQuery = SDL_GetTicks();
    80 
    81         *seconds = -1;   /* no API to estimate this in UIKit. */
    82 
    83         switch (uidev.batteryState) {
    84         case UIDeviceBatteryStateCharging:
    85             *state = SDL_POWERSTATE_CHARGING;
    86             break;
    87 
    88         case UIDeviceBatteryStateFull:
    89             *state = SDL_POWERSTATE_CHARGED;
    90             break;
    91 
    92         case UIDeviceBatteryStateUnplugged:
    93             *state = SDL_POWERSTATE_ON_BATTERY;
    94             break;
    95 
    96         case UIDeviceBatteryStateUnknown:
    97         default:
    98             *state = SDL_POWERSTATE_UNKNOWN;
    99             break;
   100         }
   101 
   102         const float level = uidev.batteryLevel;
   103         *percent = ( (level < 0.0f) ? -1 : ((int) ((level * 100) + 0.5f)) );
   104     }
   105 #endif /* TARGET_OS_TV */
   106 
   107     return SDL_TRUE; /* always the definitive answer on iOS. */
   108 }
   109 
   110 #endif /* SDL_POWER_UIKIT */
   111 #endif /* SDL_POWER_DISABLED */
   112 
   113 /* vi: set ts=4 sw=4 expandtab: */