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我放置注释图钉的目标位置的坐标?有什么方法吗?
编辑 1:
注释图钉的中心似乎从未改变过我放置图钉的位置。
- (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,droppedAt 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:
注释.m @动态启动地址;
- (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;
}
最佳答案
首先你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
MyAnnotation.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,你只需要像这样使用你的注解:
// 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,您必须为注释返回一个 View 。您可以这样做:
- (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,一旦您在 Controller 中采用了 MKMapViewDelegate
协议(protocol),您就可以像这样拖动后获取图钉的坐标:
- (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);
}
}
关于iphone - 在 map View 上拖动注释图钉,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/10733564/