DJI sdk获取RTK信息

Question

我正在尝试通过使用ios应用程序从大疆M600专业版的RTK中获取全球定位系统信息，我已经查看了DJI Mobile SDK API参考，我找到了一些RTK API。当无人机启动时，属性"isRTKBeingUsed“应该是"YES”，但我得不到结果。

任何帮助都将不胜感激！下面是我的代码：

#import "ViewController.h"
#import <DJISDK/DJISDK.h>
#import "DJIAppActivationManager_InternalTesting.h"
#import<DJISDK/DJIRTK.h>        

#define WeakRef(__obj) __weak typeof(self) __obj = self
#define WeakReturn(__obj) if(__obj ==nil)return;

void ShowResult(NSString *format, ...)
{...
}

@interface ViewController ()<DJIAppActivationManagerDelegate, DJISDKManagerDelegate,DJIRTKDelegate>     
...
...
@property (weak, nonatomic) IBOutlet UILabel *isusing;        
@property(strong, nonatomic) DJIRTK * rtk1;                  
@property(strong, nonatomic) DJIRTKState * rtkstate1;  

@end

@implementation ViewController

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
    [self registerApp];
    [self updateUI];

    self.rtk1 = [[DJIRTK alloc] init];
    self.rtkstate1 = [[DJIRTKState alloc] init];
    [self rtk:_rtk1 didUpdateState:_rtkstate1];  


}

- (void)viewDidLoad {
    [super viewDidLoad];
}


-(void) rtk:(DJIRTK *)rtk didUpdateState:(DJIRTKState *)state      
{
    self.shifoushiyong.text = [NSString stringWithFormat:@"%d",state.isRTKBeingUsed];  

}



- (void)registerApp
{
    [DJISDKManager registerAppWithDelegate:self];
}

-(void)updateUI 
{
  ...   
}

...

@end