13

注释图钉是可拖动的，但我无法将其拖放到目标位置。问题是我怎样才能得到目标位置的坐标，我把注释销放在哪里？有什么方法存在吗？

编辑1：

注释别针的中心似乎从未改变过我放下别针的地方。

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)annotationView didChangeDragState:(MKAnnotationViewDragState)newState 
fromOldState:(MKAnnotationViewDragState)oldState 
{
if (newState == MKAnnotationViewDragStateEnding)
{
    NSLog(@"x is %f", annotationView.center.x);
    NSLog(@"y is %f", annotationView.center.y);

    CGPoint dropPoint = CGPointMake(annotationView.center.x, annotationView.center.y);
    CLLocationCoordinate2D newCoordinate = [self.mapView convertPoint:dropPoint toCoordinateFromView:annotationView.superview];
    [annotationView.annotation setCoordinate:newCoordinate];

}
}

编辑2：

注释.h

@property (nonatomic,readwrite,assign) CLLocationCoordinate2D coordinate;

注释.m

- (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate {
coordinate = newCoordinate; 
}

编辑 3： 无论我在哪里拖动图钉，dropAt 的 NSLog 输出总是相同的。

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)annotationView didChangeDragState:(MKAnnotationViewDragState)newState 
fromOldState:(MKAnnotationViewDragState)oldState 
{
if (newState == MKAnnotationViewDragStateEnding)
{
    CLLocationCoordinate2D droppedAt = annotationView.annotation.coordinate;
    NSLog(@"Pin dropped at %f,%f", droppedAt.latitude, droppedAt.longitude);
}
}

编辑4：

Annotaion.m @dynamic startAddr;

- (CLLocationCoordinate2D)coordinate
{
coordinate.latitude = [self.startAddr.latitude doubleValue];
coordinate.longitude = [self.startAddr.longitude doubleValue];    
return coordinate;
}

- (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate {
//I need to update the self.startAddr.latitude and longitude here. Problem solved.
self.startAddr.latitude = [NSNumber numberWithDouble:newCoordinate.latitude];
self.startAddr.longitude = [NSNumber numberWithDouble:newCoordinate.longitude];

coordinate = newCoordinate; 
}
4

6 回答 6

39

首先，您必须像这样创建一个自定义注释：

MyAnnotation.h

#import <MapKit/MapKit.h>

@interface MyAnnotation : NSObject <MKAnnotation>{

    CLLocationCoordinate2D coordinate;

}
- (id)initWithCoordinate:(CLLocationCoordinate2D)coord;
- (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate;
@end

我的注释.m

#import "MyAnnotation.h"

@implementation MyAnnotation
@synthesize coordinate;

- (NSString *)subtitle{
    return nil;
}

- (NSString *)title{
    return nil;
}

-(id)initWithCoordinate:(CLLocationCoordinate2D)coord {
    coordinate=coord;
    return self;
}

-(CLLocationCoordinate2D)coord
{
    return coordinate;
}

- (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate {
    coordinate = newCoordinate; 
}

@end

之后，您只需要像这样使用您的注释：

// Assuming you have imported MyAnnotation.h and you have a self.map property pointing to a MKMapView
MyAnnotation *myPin = [[MyAnnotation alloc] initWithCoordinate:self.map.centerCoordinate]; // Or whatever coordinates...
[self.map addAnnotation:myPin];

此外，您必须为您的注释返回一个视图。你可以这样做：

- (MKAnnotationView *) mapView: (MKMapView *) mapView viewForAnnotation: (id<MKAnnotation>) annotation {
    MKPinAnnotationView *pin = (MKPinAnnotationView *) [self.map dequeueReusableAnnotationViewWithIdentifier: @"myPin"];
    if (pin == nil) {
        pin = [[[MKPinAnnotationView alloc] initWithAnnotation: annotation reuseIdentifier: @"myPin"] autorelease]; // If you use ARC, take out 'autorelease'
    } else {
        pin.annotation = annotation;
    }
    pin.animatesDrop = YES;
    pin.draggable = YES;

    return pin;
}

然后，一旦您MKMapViewDelegate在控制器中采用了该协议，您就可以在拖动它后抓取一个图钉的坐标，如下所示：

- (void)mapView:(MKMapView *)mapView 
 annotationView:(MKAnnotationView *)annotationView 
didChangeDragState:(MKAnnotationViewDragState)newState 
   fromOldState:(MKAnnotationViewDragState)oldState 
{
    if (newState == MKAnnotationViewDragStateEnding)
    {
        CLLocationCoordinate2D droppedAt = annotationView.annotation.coordinate;
        NSLog(@"Pin dropped at %f,%f", droppedAt.latitude, droppedAt.longitude);
    }
}
于 2012-05-24T09:25:19.383 回答
1

出乎意料的是，实现注释的 setCoordinates 方法，并在注释坐标发生变化时进行回调

编辑：当你的注解移动时要小心它的 dragState 属性。

于 2012-05-24T08:34:36.960 回答
1

难道你不想这样做：

设置注释委托，然后

- (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate {
   coordinate = newCoordinate; 
   if (self.delegate respondsToSelector:@selector(mapAnnotationCoordinateHaveChanged))
    [self.delegate performSelector(@selector(mapAnnotationCoordinateHaveChanged))];
}

在您的委托中：

- (void) mapAnnotationCoordinateHaveChanged{
 //some coordinates update code
}
于 2012-05-24T10:11:04.003 回答
1 
- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation
{
    MKAnnotationView *a = [ [ MKAnnotationView alloc ] initWithAnnotation:annotation reuseIdentifier:@"currentloc"];
    //  a.title = @"test";
    if ( a == nil )
        a = [ [ MKAnnotationView alloc ] initWithAnnotation:annotation reuseIdentifier: @"currentloc" ];

    NSLog(@"%f",a.annotation.coordinate.latitude);
    NSLog(@"%f",a.annotation.coordinate.longitude);

    CLLocation* currentLocationMap = [[[CLLocation alloc] initWithLatitude:a.annotation.coordinate.latitude longitude:a.annotation.coordinate.longitude] autorelease];
    [self coordinatesToDMS:currentLocationMap];


    MKPinAnnotationView *annView=[[MKPinAnnotationView alloc] initWithAnnotation:a reuseIdentifier:@"currentloc"];
    if(a.annotation.coordinate.longitude == mapView.userLocation.coordinate.longitude ||  a.annotation.coordinate.latitude == mapView.userLocation.coordinate.latitude  )
    {
        if ([annotation isKindOfClass:MKUserLocation.class])
        {
            //user location view is being requested,
            //return nil so it uses the default which is a blue dot...
            return nil;
        }       
        //a.image = [UIImage imageNamed:@"userlocation.png"];
        //a.pinColor=[UIColor redColor];
    }
    else 
    {

        // annView.image =[UIImage imageNamed:@"map-pin.png"];
        //PinFirst=FALSE;
        //annView.pinColor = [UIColor redColor];
        // annView.annotation=annotation;
    }

    annView.animatesDrop = YES;
    annView.draggable = YES;

    annView.canShowCallout = YES;

    return annView;
}

- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated
{
    NSLog(@"map Drag");
}

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view didChangeDragState:(MKAnnotationViewDragState)newState
fromOldState:(MKAnnotationViewDragState)oldState;
{
    NSLog(@"pin Drag");

    if (newState == MKAnnotationViewDragStateEnding)
    {
        CLLocationCoordinate2D droppedAt = view.annotation.coordinate;
        NSLog(@"Pin dropped at %f,%f", droppedAt.latitude, droppedAt.longitude);

        CLLocation* draglocation = [[[CLLocation alloc] initWithLatitude:droppedAt.latitude longitude:droppedAt.longitude] autorelease];



    }
}
于 2013-01-30T12:54:56.660 回答
0

Swift 2.2、Xcode 7.3.1 的示例：

  • 创建采用 MKAnnotation 协议的自定义类

    （注意：Swift 没有针对 KVO 兼容属性的自动通知，所以我添加了自己的 - 这不是必需的）：

    import MapKit

class MyAnnotation: NSObject, MKAnnotation {

    // MARK: - Required KVO-compliant Property
    var coordinate: CLLocationCoordinate2D {
        willSet(newCoordinate) {
            let notification = NSNotification(name: "VTAnnotationWillSet", object: nil)
            NSNotificationCenter.defaultCenter().postNotification(notification)
        }

        didSet {
            let notification = NSNotification(name: "VTAnnotationDidSet", object: nil)
            NSNotificationCenter.defaultCenter().postNotification(notification)
        }
    }


    // MARK: - Required Initializer
    init(coordinate: CLLocationCoordinate2D) {
        self.coordinate = coordinate
    }
}

  • 将 pin 视图声明为可拖动的：

    // MARK: - MKMapViewDelegate Actions
func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView? {

    let pinView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: pinViewReuseIdentifier)
    pinView.draggable = true

    return pinView
}

现在，当引脚被拖动时，它会调用委托方法：

func mapView(mapView: MKMapView, didSelectAnnotationView view: MKAnnotationView)

在这里，您可以检索新的结束坐标。

userInfo或者，您可以为自定义注释的coordinate属性通知创建字典。然后观察者可以在收到通知后检索这些值。

于 2016-08-08T22:45:44.027 回答
0

在 Swift 中，我的问题是coordinate属性是let我的子类中的 a 而var不是MKAnnotation.

class MyAnnotation  : NSObject, MKAnnotation {

    let title       : String?
    let subtitle    : String?
    var coordinate  : CLLocationCoordinate2D

    init(title: String, subtitle: String, coordinate: CLLocationCoordinate2D) {
        self.title = title
        self.subtitle = subtitle
        self.coordinate = coordinate
        super.init()
    }
}
于 2016-10-13T22:18:28.090 回答