NSArray的元素沒有匹配mapView.annotations環

Question

我想放大PinImages在圖形頁面（當它縮小或放大）雨燕數組元素類型，爲了這個，我做的事：

func resizePin(scale: CGFloat, image: UIImage) -> UIImage { 

    var newSize = CGSizeMake(image.size.width * scale, image.size.height * scale) 
    UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0) 
    image.drawInRect(CGRectMake(0, 0, newSize.width, newSize.height)) 
    var newImage = UIGraphicsGetImageFromCurrentImageContext() 
    UIGraphicsEndImageContext() 
    return newImage 
} 

在委託方法後我發現的規模和想使用resizePin方法的MapView註釋的循環內，調整它們的大小都

func mapView(mapView: MKMapView!, regionWillChangeAnimated animated: Bool) { 
    oldZoomLatitude = mapView.region.span.latitudeDelta 
    oldZoomLongitude = mapView.region.span.longitudeDelta 

} 

func mapView(mapView: MKMapView!, regionDidChangeAnimated animated: Bool) { 
    newZoomLatitude = mapView.region.span.latitudeDelta 
    newZoomLongitude = mapView.region.span.longitudeDelta 

    mapScale = (newZoomLongitude!/oldZoomLongitude!) 
    println(mapScale) 

    for annotation in mapView.annotations as [MKAnnotationView] { // EXCEPTION - fatal error: NSArray element failed to match the Swift Array Element type 
    } 
} 

不明白如何作出正確的，什麼是例外的一個原因。有任何想法嗎？

Answer 1

mapView.annotations屬性類型爲MKAnnotation。如果您想修改每個註釋的視圖，請嘗試下面的代碼：

for annotation in mapView.annotations { 
    let view = mapView.viewForAnnotation(annotation) 
    // modify the view. 
}