Objective c MKPolygonRenderer-严重的内存问题

在使用新的iOS7 MKPolygonRenderer类时，我当前面临一个硬内存问题。。我用一行代码指出了问题的根源：

[renderer invalidatePath];

核心框架似乎没有在这里释放内存，因此对该函数的后续调用会由于内存异常导致应用程序崩溃

基本上，我想做的是让用户改变地图上的单个多边形覆盖

@interface MapViewController () <MKMapViewDelegate>
{
    MKPolygonRenderer* renderer;
}
@end

@implementation MapViewController

- (id) init
{
    if ((self=[super init]) != nil)
    {
        MKMapView* viewMap = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
        viewMap.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
        viewMap.delegate = self;
        [self.view addSubview:viewMap];
        viewMap.region = MKCoordinateRegionMake(CLLocationCoordinate2DMake(49.391759,8.675766), MKCoordinateSpanMake(0.35, 0.35));

        // a simple polygon overlay with 4 points
        CLLocationCoordinate2D overlayCoords[4] = { {49.421247,8.607101}, {49.418121,8.745117}, {49.321094,8.734818}, {49.320199,8.613968}/*, {49.370199,8.583968} */};
        MKPolygon* overlay = [MKPolygon polygonWithCoordinates:overlayCoords count:4];
        [viewMap addOverlay:overlay];

        // the gesture recognizer which is used to alter the polygon
        UILongPressGestureRecognizer* longPressRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress_recognized:)];
        longPressRecognizer.minimumPressDuration = 0.1f;
        [viewMap addGestureRecognizer:longPressRecognizer];
    }
    return self;
}

- (MKOverlayRenderer*)mapView:(MKMapView*)mapView rendererForOverlay:(id<MKOverlay>)overlay
{
    // reuse the renderer if already existent
    if (self->renderer == nil)
    {
        NSLog(@" renderer is nil ==> creating");
        renderer = [[MKPolygonRenderer alloc] initWithPolygon:overlay];
        renderer.fillColor = [[UIColor darkGrayColor] colorWithAlphaComponent:0.4];
        renderer.strokeColor = [UIColor greenColor];
        renderer.lineWidth = 1;
   }
   else
       NSLog(@" renderer is not nil ==> reusing");
   return self->renderer;
}

- (void) longPress_recognized:(UILongPressGestureRecognizer*)sender
{
    if (sender.state == UIGestureRecognizerStateBegan)
    {
        // begin drag
        // check if and if yes, which polygon point is touched
        // set indexOfSelectedPoint
    }
    else if (sender.state == UIGestureRecognizerStateChanged)
    {
        // drag move

        if (indexOfSelectedMapPoint == -1)
            return;
        // get the coordinate of the user touch location
        CLLocationCoordinate2D c = [self->viewMap convertPoint:[sender locationInView:self->viewMap] toCoordinateFromView:self->viewMap];
        // update the coordinate of touched polygon point
        self->renderer.polygon.points[indexOfSelectedMapPoint] = MKMapPointForCoordinate(c);

        // this line causes the trouble 
        [renderer invalidatePath];
    }
    else if (sender.state == UIGestureRecognizerStateEnded || sender.state == UIGestureRecognizerStateCancelled)
    {
        // drag end
        // reset states
    }
}

@接口MapViewController（）
{
MKPolygonRenderer*渲染器；
}
@结束
@MapViewController的实现
-（id）init
{
if（（self=[super init]）！=nil）
{
MKMapView*viewMap=[[MKMapView alloc]initWithFrame:CGRectMake（0,0，self.view.frame.size.width，self.view.frame.size.height）]；
viewMap.autoresizingMask=uiviewsautoresizingflexiblewidth | uiviewsautoresizingflexiblewhight；
viewMap.delegate=self；
[self.view addSubview:viewMap]；
viewMap.region=MKCoordinateRegionMake（CLLocationCoordinate2DMake（49.391759,8.675766），MKCoordinateSpanMake（0.35,0.35））；
//具有4个点的简单多边形覆盖
CLLocationCoordination2d Overlycoords[4]={49.421247,8.607101}、{49.418121,8.745117}、{49.321094,8.734818}、{49.320199,8.613968}/*、{49.370199,8.583968}/}；
MKPolygon*overlay=[MKPolygon polygon with coordinates:overlayCoords count:4]；
[查看地图添加覆盖：覆盖]；
//用于改变多边形的手势识别器
UILongPressGestureRecognizer*longPressRecognizer=[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector（LongPressu recognized:）]；
longPressRecognizer.minimumPressDuration=0.1f；
[viewMap AddGestureRecognitor:LongPressRecognitor]；
}
回归自我；
}
-（MKOverlayRenderer*）地图视图：（MKMapView*）地图视图渲染器ForOverlay:（id）overlay
{
//重用渲染器（如果已经存在）
如果（自->渲染器==nil）
{
NSLog（@“渲染器为nil==>creating”）；
renderer=[[MKPolygonRenderer alloc]initWithPolygon:overlay]；
renderer.fillColor=[[UIColor darkGrayColor]colorWithAlphaComponent:0.4]；
renderer.strokeColor=[UIColor greenColor]；
1.lineWidth=1；
}
其他的
NSLog（@“渲染器不是nil==>重用”）；
返回自->渲染器；
}
-（无效）已识别长按：（UILongPressGestureRecognitor*）发送方
{
if（sender.state==UIgestureRecognitizerStateStart）
{
//开始拖动
//检查是否有，如果有，触摸的是哪个多边形点
//设置indexOfSelectedPoint
}
else if（sender.state==UIgestureRecognitizerStateChanged）
{
//拖动
如果（indexofselectedmagnate==-1）
返回；
//获取用户触摸位置的坐标
CLLocationCoordinate2D c=[self->viewMap convertPoint:[sender locationInView:self->viewMap]到CoordinateFromView:self->viewMap]；
//更新接触多边形点的坐标
self->renderer.polygon.points[indexofselectedmagnment]=MKMapPointForCoordinate（c）；
//这条线路引起了麻烦
[epath]；
}
else if（sender.state==UIGestureRecognizerStateEnded | | sender.state==UIGestureRecognizerStateCancelled）
{
//拖尾
//重置状态
}
}

我的测试项目是使用ARC。探查器没有抱怨内存泄漏

有人有类似的问题吗？ 我是不是做错了什么？ 有更好的方法吗

提前谢谢你的帮助