如何更改mapkit注释详细信息视图背景颜色？

Question

您正在尝试将注释详细信息视图（在地图图片中显示）更改为自定义设计，例如第二张图片。

如何更改背景图片？

我目前的代码是

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id)annotation {

    mapView.showsUserLocation = YES;
    if([annotation isKindOfClass:[MKUserLocation class]])
        return nil;


    static NSString *identifier = @"myAnnotation";
    MKPinAnnotationView * annotationView = (MKPinAnnotationView*)[_MAPVIEW dequeueReusableAnnotationViewWithIdentifier:identifier];
    if (!annotationView)
    {

        annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier];
        annotationView.pinColor = MKPinAnnotationColorPurple;

        annotationView.canShowCallout = YES;
    }else {
        annotationView.annotation = annotation;
    }

    UIButton *infoButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];


    [infoButton addTarget:self action:@selector(showDetailView) forControlEvents:UIControlEventTouchUpInside];
    annotationView.rightCalloutAccessoryView = infoButton;

    UIImageView *imageV=[[UIImageView alloc]initWithImage:[UIImage imageNamed:@"pin.png"]];
    annotationView.leftCalloutAccessoryView=imageV;
    return annotationView;
}

当前注释详细视图设计（当我点击pin然后我可以看到注释详细信息视图）

但我想要这样的设计

请帮帮我。