如何根据iOS中注释数组中的位置显示注释图像和标题？

Question

我试图根据它们在数组中的位置来显示注释。到目前为止，我已将所有MKPointAnnotation添加到数组中并将其添加到[mapView addAnnotation:(NSArray*)]。我还实现了-(void) mapView viewForAnnotation (-Id) MKAnnotation:annotation委托方法。我试图传递注释数组并为不同的索引显示不同的注释，但它为每个位置显示相同的图像。我怎么能搞清楚。 这是我的示例代码：

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


    NSArray *frames = [NSArray arrayWithObjects:
    [UIImage imageNamed:@"1.png"],
    [UIImage imageNamed:@"2.png"],
    [UIImage imageNamed:@"3.png"],
    [UIImage imageNamed:@"4.png"],
    [UIImage imageNamed:@"5.png"],
    nil];


    UIButton * btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    btn.frame = CGRectMake(0, 0, 20,20);
    //btn.backgroundColor = [UIColor redColor];
    [btn setTitle:@"▶️" forState:UIControlStateNormal];
    UIView *anView=[[UIView alloc] init];
    anView.backgroundColor=[UIColor redColor];

   // NSLog(@"%i",array.count);

    if([annotation isEqual:[mapView userLocation]])
    {
        //bail
        return nil;
   }

    if([annotation isKindOfClass:[MKPointAnnotation class]]) {
        MKAnnotationView *pin = (MKAnnotationView*)[mapView dequeueReusableAnnotationViewWithIdentifier:@"pin"];;

    int i ;
    for (i = 0; i<array.count; i++) {
        if(!pin){
           pin = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"pin"];
        if (i==5){
            UIImage *img = [UIImage imageNamed:@"person.png"];
            pin.image = img;
        }

        else if (i==0){
             UIImage *img = [UIImage imageNamed:@"1.png"];
            NSLog(@"%i",i);
            pin.image = img;
            pin.rightCalloutAccessoryView = btn;//[UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            pin.leftCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeInfoLight];
            pin.canShowCallout = YES;
        }

    else if (i==2){
             UIImage *img = [UIImage imageNamed:@"3.png"];
            NSLog(@"%i",i);
            pin.image = img;
            pin.rightCalloutAccessoryView = btn;//[UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            pin.leftCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeInfoLight];
            pin.canShowCallout = YES;
        }
        //NSLog(@"%i",i);
        }
}
    return pin;

    }
    return nil;


}