为什么我无法从mapview中删除我的注释？

Question

为什么我无法从mapview中删除我的注释？

我的代码：

• （无效）viewDidAppear：（BOOL）动画{ [超级viewDidAppear：动画]; [self becomeFirstResponder];

  NSMutableArray * annotations = [[NSMutableArray alloc] init]; NSString * path = [[NSBundle mainBundle] pathForResource：@“data”ofType：@“plist”]; NSDictionary * dict = [NSDictionary dictionaryWithContentsOfFile：path];如果（[[NSUserDefaults standardUserDefaults] boolForKey：@“blackKey”]） { NSLog（@“Black is on”）;

  NSArray * ann = [dict objectForKey：@“Category1”];

  的for（int i = 0;我< [安计数];我++）{

  NSString *coordinates = [[ann objectAtIndex:i] objectForKey:@"Coordinates"]; 
  
  double realLatitude = [[[coordinates componentsSeparatedByString:@","] objectAtIndex:1] doubleValue]; 
  double realLongitude = [[[coordinates componentsSeparatedByString:@","] objectAtIndex:0] doubleValue]; 
  
  MyAnnotation *myAnnotation = [[MyAnnotation alloc] init]; 
  CLLocationCoordinate2D theCoordinate; 
  theCoordinate.latitude = realLatitude; 
  theCoordinate.longitude = realLongitude; 
  
  myAnnotation.coordinate=CLLocationCoordinate2DMake(realLatitude,realLongitude); 
  
  myAnnotation.title = [[ann objectAtIndex:i] objectForKey:@"Name"]; 
  myAnnotation.subtitle = [[ann objectAtIndex:i] objectForKey:@"Address"]; 
  myAnnotation.icon = [[ann objectAtIndex:0] objectForKey:@"Icon"]; 
  
  if ([[NSUserDefaults standardUserDefaults] boolForKey:@"blackKey"]) 
  { 
      NSLog(@"Black is on"); 
      [mapView addAnnotation:myAnnotation]; 
      [annotations addObject:myAnnotation]; 
  
  } else 
      { 
       NSLog(@"Black is off"); 
  
       [self.mapView removeAnnotation:myAnnotation]; 
  
  
      } 
  
  } 
  

  }

  别的 { //什么也不做 }

  } 
  

[self.mapView removeAnnotation:myAnnotation];对我不起作用

Answer 1

没有什么可以删除的。您创建注释，然后基于blackKey的检查，您可以添加或删除它。但是，当你删除它时，你从未在此之前添加它。