更新MKannotation图像而不闪烁

Question

我想每5秒在mapview上更新一些注释的图像,但是我不想删除它们并将它们重新添加到地图中,因为这会导致它们"闪烁"或刷新,(即消失然后重新出现) .我希望它是无缝的.

我尝试过以下方法:

//get the current icon
        UserAnnotation *annotation = [self GetUserIconWithDeviceId:deviceId];

        //make a new annotation for it 
        UserAnnotation *newAnnotation = [[UserAnnotation alloc]
                                         initWithCoordinate: userCoordinates
                                         addressDictionary:nil];
        newAnnotation.title = name;
        newAnnotation.userDeviceId = deviceId;
        NSInteger ageIndicator = [[userLocation objectForKey: @"ageIndicator"] integerValue];
        newAnnotation.customImage = [UserIconHelpers imageWithAgeBorder:ageIndicator FromImage: userImage];



        //if its not there, add it 
        if (annotation != nil){
            //move it 

            //update location
            annotation.coordinate = userCoordinates;

            //add new one 
            [self.mapView addAnnotation: newAnnotation];

            //delete old one 
            [self.mapView removeAnnotation: annotation];

        } else {
        //just addd the new one 
            [self.mapView addAnnotation: newAnnotation]; 
        }

作为一个想法,如果我在顶部添加新图标,我可以删除旧图标,但这仍然导致闪烁.

有没有人有任何想法？

Answer 1

如果注释不是nil,而不是添加和删除,请尝试以下操作:

annotation.customImage = ... //the new image
MKAnnotationView *av = [self.mapView viewForAnnotation:annotation];
av.image = annotation.customImage;