您是否定义了一个实现 MKAnnotation 协议的自定义类，您在其中添加了一些属性来标识它是哪种注释?或者您是否定义了三个单独的类(每种类型的注释一个)来实现 MKAnnotation?

Have you defined a custom class that implements the MKAnnotation protocol in which you added some property that identifies what kind of annotation it is? Or have you defined three separate classes (one for each type of annotation) that implement MKAnnotation?

假设您已经定义了一个注释类，其中您的注释类中有一个名为 say annotationType 的 int 属性，那么您可以在 viewForAnnotation 中执行此操作代码>:

Assuming you've defined one annotation class in which you have an int property called say annotationType in your annotation class, then you can do this in viewForAnnotation:

int annType = ((YourAnnotationClass *)annotation).annotationType;
switch (annType)
{
    case 0 :   //Food
        pinview.pinColor = MKPinAnnotationColorRed;
    case 1 :   //Gas
        pinview.pinColor = MKPinAnnotationColorGreen;
    default :  //default or Shopping
        pinview.pinColor = MKPinAnnotationColorPurple;
}

其他一些事情:

A couple of other things:

• 您应该使用 dequeueReusableAnnotationViewWithIdentifier: 方法
• 不要使用 addTarget:action 和自定义方法来处理标注按钮按下，而是使用地图视图的委托方法 calloutAccessoryControlTapped.在该委托方法中，您可以使用 view.annotation 访问注释.

• You should use the dequeueReusableAnnotationViewWithIdentifier: method
• Instead of using addTarget:action and a custom method to handle the callout button press, use the map view's delegate method calloutAccessoryControlTapped. In that delegate method, you can access the annotation using view.annotation.