Monotouch又名xamarin ios新手。试图获得一个可以使用多个引脚的强大的mapkit。尝试一个基本的例子，我从各种各样的资源中拼凑出来，我可以找到它。
发现零星的SIGSEGV错误。当单击引脚以显示有时有效且有时不起作用的警告框时，似乎会出现某种内存错误。
我不确定我哪里出错了。这是沿着正确的方向吗？这是代码
using System;
using System.Drawing;
using MonoTouch.Foundation;
using MonoTouch.UIKit;
using MonoTouch.MapKit;
using MonoTouch.CoreLocation;
using System.Collections.Generic;
namespace singleview
{
public partial class singleviewViewController : UIViewController
{
public singleviewViewController () : base ("singleviewViewController", null)
{
}
private LocationService locationService;
private MKMapView mapView;
List<BasicMapAnnotation> pins = new List<BasicMapAnnotation>();
public override void ViewDidLoad()
{
base.ViewDidLoad();
// example of a series of map points
pins.Add(new BasicMapAnnotation(new CLLocationCoordinate2D(37.766995, -122.419580), "h", "sub1", "id1"));
pins.Add(new BasicMapAnnotation(new CLLocationCoordinate2D(37.776880, -122.418485), "i", "sub2", "id2"));
pins.Add(new BasicMapAnnotation(new CLLocationCoordinate2D(37.786775, -122.417390), "j", "sub3", "id3"));
pins.Add(new BasicMapAnnotation(new CLLocationCoordinate2D(37.796685, -122.416283), "k", "sub4", "id4"));
var currentLocation = new LocationService().GetCurrentLocation();
var visibleRegion = BuildVisibleRegion(currentLocation);
mapView = BuildMapView(true);
mapView.SetRegion(visibleRegion, true);
this.View.AddSubview(mapView);
// i have a vague idea that this delegate helps to redraw pins as user moves around screen
mapView.Delegate = new MapViewDelegate();
// this pin sometimes has a working callout that activates an alert and sometimes doesnt
var testAnnotationX = new BasicMapAnnotation (new CLLocationCoordinate2D(37.786999,-122.500222),
"made in viewdidload", "outside", "id5");
mapView.AddAnnotation(testAnnotationX);
// this pin collection also sometimes works but most often not
mapView.AddAnnotations(pins.ToArray());
}
private MKMapView BuildMapView(bool showUserLocation)
{
var view = new MKMapView()
{
ShowsUserLocation = showUserLocation,
};
view.Delegate = new MapViewDelegate();
var testAnnotationY = new BasicMapAnnotation (new CLLocationCoordinate2D(37.800000, -122.450777),
"made in buildmapview", "inside", "id6");
view.AddAnnotation(testAnnotationY);
view.SizeToFit();
view.Frame = new RectangleF(0, 0, this.View.Frame.Width, this.View.Frame.Height);
return view;
}
protected class MapViewDelegate : MKMapViewDelegate {
protected string annotationIdentifier = "BasicAnnotation";
UIButton detailButton; // avoid GC
public override MKAnnotationView GetViewForAnnotation (MKMapView mapView, NSObject annotation)
{
if (annotation is MKUserLocation) return null; //ignore user marker
annotationIdentifier = (annotation as BasicMapAnnotation).Id;
// try and dequeue the annotation view
MKAnnotationView annotationView = mapView.DequeueReusableAnnotation(annotationIdentifier);
// if we couldn't dequeue one, create a new one
if (annotationView == null)
{
annotationView = new MKPinAnnotationView(annotation, annotationIdentifier);
//annotationView.RightCalloutAccessoryView = new UIButton(UIButtonType.DetailDisclosure); //- not required as its at bottom??
// configure our annotation view properties
annotationView.CanShowCallout = true;
(annotationView as MKPinAnnotationView).AnimatesDrop = true;
(annotationView as MKPinAnnotationView).PinColor = MKPinAnnotationColor.Green;
annotationView.Selected = true;
// you can add an accessory view; in this case, a button on the right and an image on the left
detailButton = UIButton.FromType(UIButtonType.DetailDisclosure);
detailButton.TouchUpInside += (s, e) => {
Console.WriteLine ("Clicked");
new UIAlertView("Annotation Clicked", "You clicked on " +
(annotation as MKAnnotation).Coordinate.Latitude.ToString() + ", " +
(annotation as MKAnnotation).Coordinate.Longitude.ToString() , null, "OK", null).Show();
};
annotationView.RightCalloutAccessoryView = detailButton;
}
else // if we did dequeue one for reuse, assign the annotation to it
annotationView.Annotation = annotation;
/*
// configure our annotation view properties
annotationView.CanShowCallout = true;
(annotationView as MKPinAnnotationView).AnimatesDrop = true;
(annotationView as MKPinAnnotationView).PinColor = MKPinAnnotationColor.Green;
annotationView.Selected = true;
*/
// fix and uncomment
//annotationView.LeftCalloutAccessoryView = new UIImageView(UIImage.FromBundle("29_icon.png"));
return annotationView;
}
// as an optimization, you should override this method to add or remove annotations as the
// map zooms in or out.
public override void RegionChanged (MKMapView mapView, bool animated) {}
}
private MKCoordinateRegion BuildVisibleRegion(CLLocationCoordinate2D currentLocation)
{
var span = new MKCoordinateSpan(0.2,0.2);
var region = new MKCoordinateRegion(currentLocation,span);
return region;
}
public override void DidReceiveMemoryWarning ()
{
// Releases the view if it doesn't have a superview.
base.DidReceiveMemoryWarning ();
// Release any cached data, images, etc that aren't in use.
}
public override bool ShouldAutorotateToInterfaceOrientation (UIInterfaceOrientation toInterfaceOrientation)
{
// Return true for supported orientations
return (toInterfaceOrientation != UIInterfaceOrientation.PortraitUpsideDown);
}
}
public class BasicMapAnnotation : MKAnnotation{
public override CLLocationCoordinate2D Coordinate {get;set;}
string title, subtitle;
public override string Title { get{ return title; }}
public override string Subtitle { get{ return subtitle; }}
public string Id {get ;set;}
public BasicMapAnnotation (CLLocationCoordinate2D coordinate, string title, string subtitle, string id) {
this.Coordinate = coordinate;
this.title = title;
this.subtitle = subtitle;
this.Id = id;
}
}
public class LocationService
{
private CLLocationManager locationManager;
public LocationService()
{
locationManager = new CLLocationManager();
}
public CLLocationCoordinate2D GetCurrentLocation()
{
//dirty for now just to get some info.
locationManager.StartUpdatingLocation();
while(locationManager.Location == null);
locationManager.StopUpdatingLocation();
//return new CLLocationCoordinate2D ( 37.786995, -122.419280);
return locationManager.Location.Coordinate;
}
}
}
错误：
堆栈跟踪：
at（wrapper managed-to-native）MonoTouch.UIKit.UIApplication.UIApplicationMain（int，string []，intptr，intptr） 在/Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:38中的MonoTouch.UIKit.UIApplication.Main（string []，string，string）[0x0004c] at singleview.Application.Main（string []）[0x00000] in ... / singleview / Main.cs：17 at（wrapper runtime-invoke）.runtime_invoke_void_object（object，intptr，intptr，intptr）
原生堆栈跟踪：
0 singleview 0x00091eac mono_handle_native_sigsegv + 284
1 singleview 0x00005788 mono_sigsegv_signal_handler + 248
2 libsystem_c.dylib 0x938658cb _sigtramp + 43
3 ??? 0xffffffff 0x0 + 4294967295
4 UIKit 0x0274f258 -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 61
5 UIKit 0x02810021 -[UIControl sendAction:to:forEvent:] + 66
6 UIKit 0x0281057f -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 578
7 UIKit 0x0280f6e8 -[UIControl touchesEnded:withEvent:] + 546
8 UIKit 0x0277ecef -[UIWindow _sendTouchesForEvent:] + 846
9 UIKit 0x0277ef02 -[UIWindow sendEvent:] + 273
10 UIKit 0x0275cd4a -[UIApplication sendEvent:] + 436
11 UIKit 0x0274e698 _UIApplicationHandleEvent + 9874
12 GraphicsServices 0x04d40df9 _PurpleEventCallback + 339
13 GraphicsServices 0x04d40ad0 PurpleEventCallback + 46
14 CoreFoundation 0x012bfbf5 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 53
15 CoreFoundation 0x012bf962 __CFRunLoopDoSource1 + 146
16 CoreFoundation 0x012f0bb6 __CFRunLoopRun + 2118
17 CoreFoundation 0x012eff44 CFRunLoopRunSpecific + 276
18 CoreFoundation 0x012efe1b CFRunLoopRunInMode + 123
19 GraphicsServices 0x04d3f7e3 GSEventRunModal + 88
20 GraphicsServices 0x04d3f668 GSEventRun + 104
21 UIKit 0x0274bffc UIApplicationMain + 1211
22 ??? 0x0f4d71ad 0x0 + 256733613
23 ??? 0x0f4d4e40 0x0 + 256724544
24 ??? 0x0f4d4a48 0x0 + 256723528
25 ??? 0x0f4d4b9e 0x0 + 256723870
26 singleview 0x00009b52 mono_jit_runtime_invoke + 722
27 singleview 0x0016d02e mono_runtime_invoke + 126
28 singleview 0x00171224 mono_runtime_exec_main + 420
29 singleview 0x00176615 mono_runtime_run_main + 725
30 singleview 0x000671e5 mono_jit_exec + 149
31 singleview 0x00204fd4 main + 1988
32 singleview 0x00002b75 start + 53
=================================================================
Got a SIGSEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================
答案 0 :(得分：0)
看起来好老的GC错误。
看看Monotouch-Samples应用程序正是这个类和行：
https://github.com/xamarin/monotouch-samples/blob/master/MapCallouts/MainViewController.cs#L108
您需要将所有Pinview存储在某个Collection中，因此垃圾收集不会尝试收集它们。
答案 1 :(得分：0)
'var testAnnotationX'怎么样？您可能还需要移动它。