Question

有没有办法知道我的设备（iPhone）何时插入电源，如带有USB端口的电脑或汽车音响系统？我在我的应用程序中使用本地化服务，并且我希望在插入设备时自动更改为kCLLocationAccuracyBestForNavigation。感谢...

Answer 1

您可以通过UIDevice class启用电池监控并检查电池状态以查看是否正在充电：

typedef enum {
    UIDeviceBatteryStateUnknown,
    UIDeviceBatteryStateUnplugged,
    UIDeviceBatteryStateCharging,
    UIDeviceBatteryStateFull,
} UIDeviceBatteryState;

在启用最佳GPS准确度之前，您需要检查充电或充电。

Answer 2

您可以注册以在配件连接或断开连接时收到通知。

示例：

[[EAAccessoryManager sharedAccessoryManager] registerForLocalNotifications];
NSNotificationCenter *notificationCenter = [NSNotificationCenter defaultCenter];
[notificationCenter addObserver:self
                       selector:@selector(accessoryDidConnect:)
                           name:EAAccessoryDidConnectNotification
                         object:nil];
[notificationCenter addObserver:self
                       selector:@selector(accessoryDidDisconnect:)
                           name:EAAccessoryDidDisconnectNotification
                         object:nil];

收到此通知后，您可以使用for循环浏览每个附件，如：

NSArray *accessories = [[EAAccessoryManager sharedAccessoryManager] connectedAccessories]; 
EAAccessory *accessory = nil; 

for (EAAccessory *obj in accessories)
{ 
    // See if you're interested in this particular accessory
}

在某些时候（也许是dealloc），您将要取消注册这些通知。你可以这样做：

NSNotificationCenter *notificationCenter = [NSNotificationCenter defaultCenter];
[notificationCenter removeObserver:self 
                              name:EAAccessoryDidDisconnectNotification 
                            object:nil];
[notificationCenter removeObserver:self 
                              name:EAAccessoryDidConnectNotification 
                            object:nil];
[[EAAccessoryManager sharedAccessoryManager] unregisterForLocalNotifications];

Answer 3

检查电池的状态：

UIDeviceBatteryState batteryState = [[UIDevice currentDevice] batteryState];

订阅有关电池状态更改的通知，例如通过调用您自己的操作方法batteryStateChanged：

- (void) setup {
  [[UIDevice currentDevice] setBatteryMonitoringEnabled:YES];
  NSNotificationCenter * center= [NSNotificationCenter defaultCenter];
  [center addObserver:self
             selector:@selector(batteryStateChanged)
                 name:UIDeviceBatteryStateDidChangeNotification
               object:nil];
}

请记住在取消分配对象时取消订阅：

- (void) dealloc
{
   [[NSNotificationCenter defaultCenter] removeObserver:self];
   [[UIDevice currentDevice] setBatteryMonitoringEnabled:NO];
}

如何知道iOS设备何时插入？

3 个答案: