iOS版：为什么我不能得到mapkit显示自定义注释销的形象？ [英] iOS : Why can't I get mapkit to display a custom annotation pin image?

问题描述

想通，使用自己的自定义针图像注释是超级容易。

figured that using my own custom pin image for annotations would be super easy.

但我从来没有能够得到它的工作，我不知道为什么！

But I have never been able to get it to work, and I have no idea why!

我简单地使用：

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
    if([annotation isKindOfClass:[MKUserLocation class]])
        return nil;

    NSString *annotationIdentifier = @"CustomViewAnnotation";
    CustomAnnotationView * customAnnotationView = (CustomAnnotationView *) [self.mapview dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];
    if(!customAnnotationView)
    {
        customAnnotationView=[[CustomAnnotationView alloc] initWithAnnotationWithImage:annotation
                                                                       reuseIdentifier:annotationIdentifier 
                                                                   annotationViewImage:[UIImage imageNamed:@"map_location_pin.png"]];
    }

    customAnnotationView.image=[UIImage imageNamed:@"map_location_pin.png"];

    customAnnotationView.canShowCallout= YES;

    return customAnnotationView;
}

我认为这应该工作，作为一个UIImage是它想要什​​么，我有我的项目中.png文件。

I assumed that this should work, as a UIImage is what it is wanting, and I do have the .png file in my project.

它绝不会使用我的形象，只是标准的红脚。我在做什么错在这里？

It never uses my image, but just the standard red pin. What am I doing wrong here?

推荐答案

一对夫妇的想法：

1. 你定义你的委托您的MKMapView ？你在这里放一个断点或的NSLog ，以确保您的 viewForAnnotation 获取调用？

1. Did you define your delegate for your MKMapView? Have you put a breakpoint or NSLog in here to make sure your viewForAnnotation is getting called?

您还没有分享你的 CustomAnnotationView 接口/实现细节，但你并不需要继承 MKAnnotationView ，除非你正在做的东西在里面特别。如果你刚刚更换的图像，你可以这样做：

You haven't shared your CustomAnnotationView interface/implementation details, but you don't need to subclass MKAnnotationView unless you're doing something special in there. If you're just replacing the image, you can just do:

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
    if([annotation isKindOfClass:[MKUserLocation class]]) {
        return nil;
    }

    NSString *annotationIdentifier = @"CustomViewAnnotation";
    MKAnnotationView* annotationView = [mapview dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

    if (annotationView) {
        annotationView.annotation = annotation;
    } else {
        annotationView = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:annotationIdentifier];
    }

    annotationView.image = [UIImage imageNamed:@"map_location_pin.png"];
    annotationView.canShowCallout= YES;

    return annotationView;
}

由此可见，虽然，如果你（当引脚被拖动或丢弃，如自定义注释）做一些有趣的事情，然后继续前进，有你的 CustomAnnotationView 子 MKAnnotationView 。这只是取决于你想要做的事。

Clearly, though, if you're doing something interesting (like custom annotation when a pin is dragged or dropped), then go ahead and have your CustomAnnotationView subclass MKAnnotationView. It just depends upon what you're trying to do.

无关的你原来的问题，我建议：

Unrelated to your original question, I'd suggest:

• 这是你的 viewForAnnotation 方法只使用本地图形页面，而不是变量引用类属性， self.mapView （虽然他们无疑是相同的），

• that your viewForAnnotation method just use the local mapView variable rather than referencing a class property, self.mapView (though they're undoubtedly the same),

这是你考虑重命名您的自定义init方法。因此，而不是：

that you contemplate renaming your custom init method. So instead of:

customAnnotationView = [[CustomAnnotationView alloc] initWithAnnotationWithImage:annotation
                                                                 reuseIdentifier:annotationIdentifier 
                                                             annotationViewImage:[UIImage imageNamed:@"map_location_pin.png"]];

这是你会做这样的事情：

that you'd do something like:

customAnnotationView = [[CustomAnnotationView alloc] initWithAnnotation:annotation
                                                        reuseIdentifier:annotationIdentifier 
                                                                  image:[UIImage imageNamed:@"map_location_pin.png"]];

如果你还有问题，分享一些你的 CustomAnnotationView $ C $的c。与我们联系。

If you're still having troubles, share some of your CustomAnnotationView code with us.

这篇关于iOS版：为什么我不能得到mapkit显示自定义注释销的形象？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！