有没有办法添加一个 ID 或其他东西,我可以设置自定义标记图像?
我有多个带数字的标记,我需要每个新标记都有另一个图像。
例如:
marker1 - marker_1_image
marker2 - marker_2_image
Atm 我只能为所有标记设置 1 个图像(全局):
func mapView(mapView: MGLMapView, imageForAnnotation annotation: MGLAnnotation) -> MGLAnnotationImage? {
var annotationImage = mapView.dequeueReusableAnnotationImageWithIdentifier("place")
if annotationImage == nil {
var image = UIImage(named: "marker_1")!
image = image.imageWithAlignmentRectInsets(UIEdgeInsetsMake(0, 0, image.size.height/2, 0))
annotationImage = MGLAnnotationImage(image: image, reuseIdentifier: "place")
}
return annotationImage
}
有什么想法吗?或者我可以子类化 MGLAnnotation 并将其用于所有委托(delegate)方法吗?
最佳答案
您可以子类化并添加一个 userInfo
属性 ( as in this answer ),或者您可以使用现有的标题/副标题属性:
func mapView(mapView: MGLMapView, imageForAnnotation annotation: MGLAnnotation) -> MGLAnnotationImage? {
// get the custom reuse identifier for this annotation
let reuseIdentifier = reuseIdentifierForAnnotation(annotation)
// try to reuse an existing annotation image, if it exists
var annotationImage = mapView.dequeueReusableAnnotationImageWithIdentifier(reuseIdentifier)
// if the annotation image hasn‘t been used yet, initialize it here with the reuse identifier
if annotationImage == nil {
// lookup the image for this annotation
let image = imageForAnnotation(annotation)
annotationImage = MGLAnnotationImage(image: image, reuseIdentifier: reuseIdentifier)
}
return annotationImage
}
// create a reuse identifier string by concatenating the annotation coordinate, title, subtitle
func reuseIdentifierForAnnotation(annotation: MGLAnnotation) -> String {
var reuseIdentifier = "\(annotation.coordinate.latitude),\(annotation.coordinate.longitude)"
if let title = annotation.title where title != nil {
reuseIdentifier += title!
}
if let subtitle = annotation.subtitle where subtitle != nil {
reuseIdentifier += subtitle!
}
return reuseIdentifier
}
// lookup the image to load by switching on the annotation's title string
func imageForAnnotation(annotation: MGLAnnotation) -> UIImage {
var imageName = ""
if let title = annotation.title where title != nil {
switch title! {
case "blah":
imageName = "blahImage"
default:
imageName = "defaultImage"
}
}
// ... etc.
return UIImage(named: imageName)!
}
您会希望使图像加载更稳健并自定义重用标识符字符串的特异性,但这通常应该可行。
关于ios - MapBox iOS 不同的标记图像?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36115342/