带按钮的Ios Map注释

Question

我有viewforAnnotation的定义：

        - (MKPinAnnotationView *)mapView:(MKMapView *)mV viewForAnnotation:(id        <MKAnnotation>)annotation{

    MKPinAnnotationView *view = nil;
    //MKPinAnnotationView *view=[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"HotSpotsLoc"];

    if(annotation !=mapView.userLocation){
        view = (MKPinAnnotationView *)
        [mapView dequeueReusableAnnotationViewWithIdentifier:@"identifier"];
        if(nil == view) {
            view = [[MKPinAnnotationView alloc]
                     initWithAnnotation:annotation reuseIdentifier:@"identifier"];
        }



        UIButton *btnViewVenue = [UIButton buttonWithType:UIButtonTypeSystem];
        [btnViewVenue setTitle:@"Foo" forState:UIControlStateNormal];
        view.rightCalloutAccessoryView=btnViewVenue;
        view.enabled = YES;
        view.pinColor = MKPinAnnotationColorPurple;
        view.canShowCallout = YES;
        view.multipleTouchEnabled = NO;
        //view.animatesDrop = YES;

    }       
    return view;
}

它通常有效，添加按钮等。但是当我补充说：

 [btnViewVenue setTitle:@"Foo" forState:UIControlStateNormal];

要设置按钮的标题，程序不再起作用，我无法添加任何注释或任何东西，只需要mapview。谁能告诉我有什么问题？ 感谢。

Answer 1

更改此

UIButton *btnViewVenue = [UIButton buttonWithType:UIButtonTypeSystem];

到

UIButton *btnViewVenue = [UIButton buttonWithType:UIButtonTypeCustom];