使用CMPedometer进行实时更新(CoreMotion)

时间:2016-04-06 01:33:45

标签: ios objective-c core-motion

我发现这个主题的资源非常有限(CMPedometer)。我想知道是否有人在这里设法让这个正常工作。我的代码非常简单,并且比我尝试的更多。基本上,步数计数器不会增加用户采取的每一步。

它实际上是跟踪用户所采取的每一步,但它更新得如此缓慢,我无法弄清楚原因。我甚至尝试使用NSTimer来请求每半秒更新一次标签。我想尝试让步骤计数器在用户采取步骤时进行更新。这是我的代码......

#import "ViewController.h"
#import <CoreMotion/CoreMotion.h>

@interface ViewController ()

@property (nonatomic, strong) CMPedometer    *pedometer;
@property (nonatomic, weak) IBOutlet UILabel *startDateLabel;
@property (nonatomic, weak) IBOutlet UILabel *endDateLabel;
@property (nonatomic, weak) IBOutlet UILabel *stepsLabel;
@property (nonatomic, weak) IBOutlet UILabel *distanceLabel;
@property (nonatomic, weak) IBOutlet UILabel *ascendedLabel;
@property (nonatomic, weak) IBOutlet UILabel *descendedLabel;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    if ([CMPedometer isStepCountingAvailable]) {
        self.pedometer = [[CMPedometer alloc] init];
        [NSTimer scheduledTimerWithTimeInterval:0.5f
                                         target:self
                                       selector:@selector(recursiveQuery)
                                       userInfo:nil
                                        repeats:YES];
    } else {
        NSLog(@"Nothing available");
        self.startDateLabel.text = @"";
        self.endDateLabel.text   = @"";
        self.stepsLabel.text     = @"";
        self.distanceLabel.text  = @"";
        self.ascendedLabel.text  = @"";
        self.descendedLabel.text = @"";
    }

}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];

    [self.pedometer startPedometerUpdatesFromDate:[NSDate date]
                                      withHandler:^(CMPedometerData *pedometerData, NSError *error) {
                                          dispatch_async(dispatch_get_main_queue(), ^{
                                              NSLog(@"data:%@, error:%@", pedometerData, error);
                                          });
                                      }];
}


- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    [self.pedometer stopPedometerUpdates];
}

- (NSString *)stringWithObject:(id)obj {
    return [NSString stringWithFormat:@"%@", obj];
}

- (NSString *)stringForDate:(NSDate *)date {

    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    formatter.dateStyle = NSDateFormatterShortStyle;
    formatter.timeStyle = NSDateFormatterShortStyle;

    return [formatter stringFromDate:date];
}

- (void)queryDataFrom:(NSDate *)startDate toDate:(NSDate *)endDate {
    [self.pedometer queryPedometerDataFromDate:startDate
                                        toDate:endDate
                                   withHandler:
     ^(CMPedometerData *pedometerData, NSError *error) {

         NSLog(@"data:%@, error:%@", pedometerData, error);

         dispatch_async(dispatch_get_main_queue(), ^{
             if (error) {
                 NSLog(@"Error = %@",error.userInfo);
                 self.startDateLabel.text = @"";
                 self.endDateLabel.text   = @"";
                 self.stepsLabel.text     = @"";
                 self.distanceLabel.text  = @"";
                 self.ascendedLabel.text  = @"";
                 self.descendedLabel.text = @"";
             } else {
                 self.startDateLabel.text = [self stringForDate:pedometerData.startDate];
                 self.endDateLabel.text   = [self stringForDate:pedometerData.endDate];
                 self.stepsLabel.text     = [self stringWithObject:pedometerData.numberOfSteps];
                 self.distanceLabel.text  = [NSString stringWithFormat:@"%.1f[m]", [pedometerData.distance floatValue]];
                 self.ascendedLabel.text  = [self stringWithObject:pedometerData.floorsAscended];
                 self.descendedLabel.text = [self stringWithObject:pedometerData.floorsDescended];
             }
         });
     }];
}

- (void)recursiveQuery {
    NSDate *to   = [NSDate date];
    NSDate *from = [to dateByAddingTimeInterval:-(24. * 3600.)];
    [self queryDataFrom:from toDate:to];
}

提前感谢您的任何反馈!

修改

似乎用于实时更新的适当方法如下..

- (void)liveSteps {
    [self.pedometer startPedometerUpdatesFromDate:[NSDate date]
                                      withHandler:^(CMPedometerData *pedometerData, NSError *error) {
                                          dispatch_async(dispatch_get_main_queue(), ^{
                                              NSLog(@"Steps %@",pedometerData.numberOfSteps);
                                          });
                                      }];
}

然而,即使这种情况严重延迟。有没有人知道如何正确地使用它来实质上更新,因为用户采取了一步?

1 个答案:

答案 0 :(得分:3)

我只能确认你的发现。我也希望获得“真实”的实时信息。在这一点上,API似乎无法做到这一点;甚至通过强制更新进入队列,同步,异步等等。

对于有这个问题的参考和其他人,这里是我使用的基于Swift 3和Xcode 8.2的代码。在检查CMPedometer.isStepCountingAvailable()之后,我只需在相关的viewcontroller中应用这部分代码。

正如您所看到的,我已经包含了一个小动画,以更流畅的方式更新UILabel。

    // Steps update in near realtime - UILabel
    self.pedoMeter.startUpdates(from: midnightOfToday) { (data: CMPedometerData?, error) -> Void in

        DispatchQueue.main.async(execute: { () -> Void in
            if(error == nil){
                self.todaySteps.text = "\(data!.numberOfSteps)"
                // Animate the changes of numbers in the UILabel
                UILabel.transition(with: self.todaySteps,
                                   duration: 0.50,
                                   options: .transitionCrossDissolve,
                                   animations: nil,
                                   completion: nil)
            }
        })
    }