iphone - MKMapView 加载时覆盖除 View 之外的所有内容？仅限iOS5<

Question

出于某种原因，我的 MKMapView 有时会覆盖覆盖除加载时 View 之外的所有内容。您可以在 View 加载后滚动到一侧并查看叠加层。另外，该问题仅在ios5及以下版本中存在，在ios6中不会出现该问题。我发现，如果放大或缩小 map ， map 的覆盖部分将调整为新 View 。例如，如果您缩小，则 map 的非重叠部分将调整并变大以适应 View 的新尺寸，但如果您向侧面滚动，则 map 仍然以 viewForOverlay 中定义的颜色全部重叠方法。我不知道为什么，已经研究了一段时间了，谷歌没有发现任何东西。这是我的一些代码:

-(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

我怀疑问题出在您创建 MKPolyline 或 lineSize 设置上。此代码在这里运行良好:

#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