加载后，MKMapView会覆盖除视图之外的所有内容吗？只有iOS5＆lt;

Question

由于某种原因，我的MKMapView有时会覆盖除加载时视图以外的所有内容。您可以在视图加载后滚动到侧面并查看叠加层。此外，此问题仅存在于ios5及更低版本中，ios6中不会出现此问题。我发现如果你在地图上放大或缩小，地图的重叠部分将调整到新视图。例如，如果缩小，则地图的非重叠部分将调整并增大到视图的新大小，但如果然后向侧面滚动，则地图仍然全部覆盖在viewForOverlay中定义的颜色中方法。我不知道为什么，一直在研究这个问题，谷歌没有做任何事情。以下是我的一些代码：

-(MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id <MKOverlay>)overlay {

    if([overlay class] == [MKPolyline class]){
    MKPolylineView *polylineView = [[MKPolylineView alloc] initWithPolyline:overlay];

    int lineSize = [self.ud integerForKey:@"lineSize"];
    polylineView.lineWidth = lineSize;

    NSString *lineColor = [self.ud objectForKey:@"lineColor"];

    if([lineColor isEqualToString:@"Red"]){
        polylineView.strokeColor = [UIColor redColor];
    }else if([lineColor isEqualToString:@"Blue"]){
        polylineView.strokeColor = [UIColor blueColor];
    }else if ([lineColor isEqualToString:@"Orange"]){
        polylineView.strokeColor = [UIColor orangeColor];
    }else if([lineColor isEqualToString:@"Green"]){
        polylineView.strokeColor = [UIColor greenColor];
    }else if([lineColor isEqualToString:@"Black"]){
        polylineView.strokeColor = [UIColor blackColor];
    }
    return polylineView;
    }else{
        MKOverlayView *overlayToReturn = [[MKOverlayView alloc]initWithOverlay:overlay];
        return overlayToReturn;
    }
}

这就是我得到的：

Answer 1

我怀疑问题出在你创建的MKPolyline或lineSize设置上。这段代码在这里工作正常：

#import <MapKit/MapKit.h>
#import "ViewController.h"

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    MKMapView *map = [[MKMapView alloc] initWithFrame:self.view.bounds];
    map.delegate = self;
    [self.view addSubview:map];

    CLLocationCoordinate2D coords[] = { {42,-83}, {32, -84}, {45,-78}, {42,-83} };
    MKPolyline *overlay = [MKPolyline polylineWithCoordinates:coords count:4];
    [map addOverlay:overlay];
}

-(MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id <MKOverlay>)overlay {

    if([overlay class] == [MKPolyline class]){
    MKPolylineView *polylineView = [[MKPolylineView alloc] initWithPolyline:overlay];

    int lineSize = 2; //[self.ud integerForKey:@"lineSize"];
    polylineView.lineWidth = lineSize;

    NSString *lineColor = @"Red"; // [self.ud objectForKey:@"lineColor"];

    if([lineColor isEqualToString:@"Red"]){
        polylineView.strokeColor = [UIColor redColor];
    }else if([lineColor isEqualToString:@"Blue"]){
        polylineView.strokeColor = [UIColor blueColor];
    }else if ([lineColor isEqualToString:@"Orange"]){
        polylineView.strokeColor = [UIColor orangeColor];
    }else if([lineColor isEqualToString:@"Green"]){
        polylineView.strokeColor = [UIColor greenColor];
    }else if([lineColor isEqualToString:@"Black"]){
        polylineView.strokeColor = [UIColor blackColor];
    }
    return polylineView;
    }else{
        MKOverlayView *overlayToReturn = [[MKOverlayView alloc]initWithOverlay:overlay];
        return overlayToReturn;
    }
}

@end