子类化MKAnnotationView并重写setDragState

我有引脚拖动工作,但试图找出为什么引脚周年纪念发生时,你不覆盖setDragState-不再在我的实现工作。你的问题包含了我的答案。。谢谢!

下面是我最终得到的代码(在您的帮助下),它按照我预期的方式执行所有的提升、拖动和下降操作。希望这对你也有帮助!

- (void)setDragState:(MKAnnotationViewDragState)newDragState animated:(BOOL)animated
{
    if (newDragState == MKAnnotationViewDragStateStarting)
    {
        // lift the pin and set the state to dragging

        CGPoint endPoint = CGPointMake(self.center.x,self.center.y-20);
        [UIView animateWithDuration:0.2
                         animations:^{ self.center = endPoint; }
                         completion:^(BOOL finished)
                             { self.dragState = MKAnnotationViewDragStateDragging; }];
    }
    else if (newDragState == MKAnnotationViewDragStateEnding)
    {
        // save the new location, drop the pin, and set state to none

        /* my app specific code to save the new position
        objectObservations[ACTIVE].latitude = pinAnnotation.coordinate.latitude;
        objectObservations[ACTIVE].longitude = pinAnnotation.coordinate.longitude;
        posChanged = TRUE;
        */

        CGPoint endPoint = CGPointMake(self.center.x,self.center.y+20);
        [UIView animateWithDuration:0.2
                         animations:^{ self.center = endPoint; }
                         completion:^(BOOL finished)
                             { self.dragState = MKAnnotationViewDragStateNone; }];
    }
    else if (newDragState == MKAnnotationViewDragStateCanceling)
    {
        // drop the pin and set the state to none

        CGPoint endPoint = CGPointMake(self.center.x,self.center.y+20);
        [UIView animateWithDuration:0.2
                         animations:^{ self.center = endPoint; }
                         completion:^(BOOL finished)
                             { self.dragState = MKAnnotationViewDragStateNone; }];
    }
}

Brian's solution 如果成功的话,它没有考虑到用户手指阻塞正在被操纵的注释视图。

这意味着用户在拖动pin时无法精确放置pin。标准 MKPinAnnotationView 在这方面做得很好,当手指开始拖动时,销被提升到手指上方,销的可视点用于放置,而不是位于手指下方的先前中心点。

除此之外,我的实现还添加了另一个动画,当拖动后放下管脚时,通过提升管脚并以更高的速度放下管脚。这与本机用户体验非常接近,您的用户将对此表示赞赏。

请查看我的 gist on GitHub for the code .

真正酷的是将委托设置为可选的,当注释视图放回地图上时,可以选择发送通知。

我没怎么研究本的代码,但它对我不起作用。所以我试了布赖恩的,效果很好。谢谢!很长一段时间以来,我一直在尝试解决拖放过程中注释的动画问题。

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)annotationView didChangeDragState:(MKAnnotationViewDragState)newState fromOldState:(MKAnnotationViewDragState)oldState . 这是我的密码:

DragTableAnnotationView.h:

#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>

@interface DraggableAnnotationView : MKAnnotationView 
{
    id <MKMapViewDelegate> delegate;
    MKAnnotationViewDragState dragState;
}

@property (nonatomic, assign) id <MKMapViewDelegate> delegate;
@property (nonatomic, assign) MKAnnotationViewDragState dragState;
@property (nonatomic, assign) MKMapView *mapView;

@end

#import "DraggableAnnotationView.h"
#import "MapAnnotation.h"

@implementation DraggableAnnotationView
@synthesize delegate, dragState, mapView;



- (void)setDragState:(MKAnnotationViewDragState)newDragState animated:(BOOL)animated
{
    [delegate mapView:mapView annotationView:self didChangeDragState:newDragState fromOldState:dragState];

    if (newDragState == MKAnnotationViewDragStateStarting) {
        // lift the pin and set the state to dragging
        CGPoint endPoint = CGPointMake(self.center.x,self.center.y-20);
        [UIView animateWithDuration:0.2
                         animations:^{ self.center = endPoint; }
                         completion:^(BOOL finished)
         { dragState = MKAnnotationViewDragStateDragging; }];
    } else if (newDragState == MKAnnotationViewDragStateEnding) {
        // drop the pin, and set state to none

        CGPoint endPoint = CGPointMake(self.center.x,self.center.y+20);
        [UIView animateWithDuration:0.2
                         animations:^{ self.center = endPoint; }
                         completion:^(BOOL finished)
         { dragState = MKAnnotationViewDragStateNone; }];
    } else if (newDragState == MKAnnotationViewDragStateCanceling) {
        // drop the pin and set the state to none

        CGPoint endPoint = CGPointMake(self.center.x,self.center.y+20);
        [UIView animateWithDuration:0.2
                         animations:^{ self.center = endPoint; }
                         completion:^(BOOL finished)
         { dragState = MKAnnotationViewDragStateNone; }];
    }
}

- (void)dealloc 
{
    [super dealloc];
}

@end