Question

我一直在寻找好几个小时，试图获取并更新某些内容以便在iOS 5上使用drop和drag pin。我认为我非常接近...但是在尝试初始化自定义注释时存货。

这是我的班级

.h
@interface AnnotationView : MKAnnotationView ...

.m
@interface AnnotationView () 
@property (nonatomic, assign) BOOL hasBuiltInDraggingSupport;
@end

@implementation AnnotationView
@synthesize hasBuiltInDraggingSupport, mapView;


- (id)initWithAnnotation:(id <MKAnnotation>)annotation reuseIdentifier:(NSString *)reuseIdentifier {

self.hasBuiltInDraggingSupport = [[MKAnnotationView class] instancesRespondToSelector:NSSelectorFromString(@"isDraggable")];

if (self.hasBuiltInDraggingSupport) {
    if ((self = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:reuseIdentifier])) {
        [self performSelector:NSSelectorFromString(@"setDraggable:") withObject:[NSNumber numberWithBool:YES]];
    }
}

self.canShowCallout = YES;
return self;
}
@end

问题在于

self = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:reuseIdentifier]

它说：从'MKPinAnnotationView *'

分配给'AnnotationView * __strong'的指针类型不兼容

此外，下一行是警告

[self performSelector:NSSelectorFromString(@"setDraggable:") withObject:[NSNumber numberWithBool:YES]];

THX

警告说setDraggable：selector是未知的......但不应该从

中删除

Answer 1

- (MKAnnotationView *)mapView:(MKMapView *)theMapView viewForAnnotation:(id<MKAnnotation>)annotation
{
    MKPinAnnotationView* annView = (MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:@"xxx"];
    // check conditions for class of annview or other    
    annView.draggable = YES;
}

MapView Drop and Drag Pin - 自定义MKAnnotationView iOS 5

1 个答案: