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mkannontation pin图像大小调整问题

mkannotationview mkmapview swift ios

PvDev · 技术社区 · 5 年前

自定义的PIN图像 MKAnnotation . 当点击或缩放地图时,自定义的别针会被拉伸,并且主地图汽车的别针标记的开口很大。以下是我在MapView中得到的输出结果:

以下是迄今为止我尝试过的代码:

var pin = MKAnnotationView()
var userPinView: MKAnnotationView!

if annotation is MKUserLocation {

    pin = mapView.view(for: annotation) ?? MKAnnotationView(annotation: annotation, reuseIdentifier: nil)
    let pinImage = UIImage(named: "carIcon3")
    let size = CGSize(width: 38, height: 44)
    UIGraphicsBeginImageContext(size)
    pinImage!.draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
    let resizedImage = UIGraphicsGetImageFromCurrentImageContext()
    pin.image = resizedImag
    userPinView = pin
    userPinView.contentMode = .scaleAspectFill
    userPinView.clipsToBounds = true
    return pin
}

if !(annotation is MKPointAnnotation) {
    return nil
}

let annotationIdentifier = "AnnotationIdentifier"
var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: annotationIdentifier)

if annotationView == nil {
    annotationView = MKAnnotationView(annotation: annotation, reuseIdentifier: annotationIdentifier)
    //            annotationView!.canShowCallout = true
} else {
    annotationView!.annotation = annotation
}
return annotationView

如何得到这样的结果:

尝试使用当前位置标记。但它崩溃了

   func locationManager(_ manager: CLLocationManager, didUpdateHeading newHeading: CLHeading) {

        UIView.animate(withDuration: 0.005) {

        let angle = newHeading.trueHeading.toRadians() // convert from degrees to radians

        self.userPinView.transform = CGAffineTransform(rotationAngle: CGFloat(angle)) // rotate the picture
    }
}

这里是我为位置注释执行的didselect和deselect代码。

     func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {

    if annotView == true {

        let heights = 70

        let widths = 50

        UIView.animate(withDuration: 0.5, delay: 0.0, options: .curveLinear, animations: {

            view.frame.size = CGSize(width: widths, height: heights)

        })
    }

}

func mapView(_ mapView: MKMapView, didDeselect view: MKAnnotationView) {

    let heights = 70

    let widths = 50

    UIView.animate(withDuration: 0.5, delay: 0.0, options: .curveLinear, animations: {

        view.frame.size = CGSize(width: view.frame.width - CGFloat(widths), height: view.frame.height - CGFloat(heights))

    })
}

1 回复 | 直到 5 年前

AamirR 5 年前

虽然我不能重现这个问题,但我建议进行以下几点修改:

分离视图配置逻辑,让子类 MKAnnotationView ,像这样:

class CarAnnotationView: MKAnnotationView {
    override var annotation: MKAnnotation? {
        didSet {
            let size = CGSize(width: 38, height: 44)
            UIGraphicsBeginImageContext(size)
            UIImage(named: "carIcon")?.draw(in: CGRect(origin: .zero, size: size))
            self.image = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()
        }
    }
}

内变化 mapView(_:viewFor:) 要利用可重用视图,例如:

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation {
        userPinView = mapView.dequeueReusableAnnotationView(withIdentifier: "carId") as? CarAnnotationView
        if (userPinView == nil) {
            userPinView = CarAnnotationView(annotation: nil, reuseIdentifier: "carId")
        }

        userPinView.annotation = annotation
        userPinView.setNeedsLayout()
        // userPinView.centerOffset = CGPoint(x: 0, y: -view.bounds.midY)

        return userPinView
    }

    guard annotation is MKPointAnnotation else { return nil }

    let annotationIdentifier = "AnnotationIdentifier"
    ...
    return annotationView

}

删除不必要的变量
```
var pin = MKAnnotationView()
```