MonoTouch - ScrollView + Any event = Crash_问答_开发者

I'm really stumped. I have a View with ScrollView on it and a label. The scrolling works fine when this is the case. I put on a button, created the clickFoo action, and put in the Partial code like I have on dozens of UIViews, but now it causes a horrific stacktrace (see below). I get the same if I remove the button and action but put in a handler for the Scrolling event of the UIScrollView. I'm stumped why this is happening. This is really, really simple stuff, makes no sense.

For the record, the scrollview is 100x40, and the label and button are NOT in the scrollview.

I have the following code in my ViewDidLoad

    public partial class Testing : UIViewController
{
    #region Constructors

    // The IntPtr and initWithCoder constructors are required for items that need 
    // to be able to be created from a xib rather than from managed code

    public Testing (IntPtr handle) : base(handle)
    {
        Initialize ();
    }

    [Export("initWithCoder:")]
    public Testing (NSCoder coder) : base(coder)
    {
        Initialize ();
    }

    public Testing () : base("Testing", null)
    {
        Initialize ();
    }

    void Initialize ()
    {
    }

    #endregion
    List<UIImageView> _imageViews;

    public override void ViewDidLoad ()
    {
        base.ViewDidLoad ();

        _imageViews = new List<UIImageView>();

        UIButton btnNumber;
        /*              btnNumber = new UIButton(new RectangleF(new PointF(32f*x,0f), new SizeF(31f,31f)));
            btnNumber.SetImage(UIImage.FromBundle("images/7.png"), UIControlState.Normal);
            btnNumber.SetImage(UIImage.FromBundle("images/7.png"), UIControlState.Highlighted);*/
        UIImageView imgView;

        scrollView.ContentSize = new System.Drawing.SizeF(400, 31);

        for (int x=0;x < 30; x++) {         
            imgView = new UIImageView(new RectangleF(new PointF(32f*x,0f), new SizeF(31f,31f)));
            imgView.Image = UIImage.FromBundle("images/7.png");
            scrollView.AddSubview(imgView);
            _imageViews.Add(imgView);
        }

    }

    partial void clickFoo (UIButton sender)
    {
        lblInfo.Text = "Clicked";
    }

} [ Code pasted in updated @12:07pm EDT ]

I get the following exception stack (which I find is the classic "Hey, SOMETHING EVENT RELATED is wrong, somewhere", very frustrating)

Stacktrace:

  at (wrapper managed-to-native) MonoTouch.UIKit.UIApplication.UIApplicationMain (int,string[],intptr,intptr) <0x00004>
  at (wrapper managed-to-native) MonoTouch.UIKit.UIApplication.UIApplicationMain (int,string[],intptr,intptr) <0x00004>
  at MonoTouch.UIKit.UIApplication.Main (string[],string,string) [0x00038] in /Users/plasma/Source/iphone-3/monotouch/UIKit/UIApplication.cs:26
  at MonoTouch.UIKit.UIApplication.Main (string[]) [0x00000] in /Users/plasma/Source/iphone-3/monotouch/UIKit/UIApplication.cs:31
  at ZenVelopes.Application.Main (string[]) [0x00000] in /Users/drisszouak/Projects/ZenVelopes/ZenVelopes/Main.cs:14
  at (wrapper runtime-invoke) <Module>.runtime_invoke_void_object (object,intptr,intptr,intptr) <IL 0x0001d, 0x00043>

Native stacktrace:

    0   ZenVelopes                          0x000be9db mono_handle_native_sigsegv + 343
    1   ZenVelopes                          0x0000e7a6 mono_sigsegv_signal_handler + 313
    2   libSystem.B.dylib                   0x918db46b _sigtramp + 43
    3   ???                                 0xffffffff 0x0 + 4294967295
    4   UIKit                               0x01c721b5 -[UIControl sendAction:to:forEvent:] + 67
    5   UIKit                               0x01c74647 -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 527
    6   UIKit                               0x01c731f4 -[UIControl touchesEnded:withEvent:] + 458
    7   UIKit                               0x01c080d1 -[UIWindow _sendTouchesForEvent:] + 567
    8   UIKit                               0x01be937a -[UIApplication sendEvent:] + 447
    9   UIKit                               0x01bee732 _UIApplicationHandleEvent + 7576
    10  GraphicsServices                    0x03eb9a36 PurpleEventCallback + 1550
    11  CoreFoundation                      0x00dfb064 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 52
    12  CoreFoundation                      0x00d5b6f7 __CFRunLoopDoSource1 + 215
    13  CoreFoundation                      0x00d58983 __CFRunLoopRun + 979
    14  CoreFoundation                      0x00d58240 CFRunLoopRunSpecific + 208
    15  CoreFoundation                      0x00d58161 CFRunLoopRunInMode + 97
    16  GraphicsServices                    0x03eb8268 GSEventRunModal + 217
    17  GraphicsServices                    0x03eb832d GSEventRun + 115
    18  UIKit                               0x01bf242e UIApplicationMain + 1160
    19  ???                                 0x09e28c41 0x0 + 165841985
    20  ???                                 0x09e28b7a 0x0 + 165841786
    21  ???                                 0x09e2857d 0x0 + 165840253
    22  ???                                 0x09e284b9 0x0 + 165840057
    23  ???                                 0x09e28514 0x0 + 165840148
    24  ZenVelopes                          0x0000e56a mono_jit_runtime_invoke + 1360
    25  ZenVelopes                          0x001c961b mono_runtime_invoke + 137
    26  ZenVelopes                          0x001cb2d7 mono_runtime_exec_main + 714
    27  ZenVelopes                          0x001cabfd mono_runtime_run_main + 812
    28  ZenVelopes                          0x00095354 mono_jit_exec + 200
    29  ZenVelopes                          0x0027d299 main + 3494
    30  ZenVelopes                          0x00003009 _start + 208
    31  ZenVelopes                          0x00002f38 start + 40

Debug info from gdb:

warning: .o file "/Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(monotouch-glue.x86.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(monotouch-glue.x86.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: .o file "/Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(monotouch-x86.double-abi-stret-trampoline.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(monotouch-x86.double-abi-stret-trampoline.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: .o file "/Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(gc.x86.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(gc.x86.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: .o file "/Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(zlib-helper.x86.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(zlib-helper.x86.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: Could not find object file "/var/folders/Ny/NyElTwhDGD8kZMqIEeLGXE+++TI/-Tmp-//ccvRqNHg.o" - no debug information available for "template.m".

warning: .o file "/Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_divdi3.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_divdi3.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: .o file "/Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_moddi3.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_moddi3.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: .o file "/Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_udivdi3.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_udivdi3.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
warning: .o file "/Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_umoddi3.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Could not open OSO file /Developer/usr/lib/gcc/i686-apple-darwin10/4.2.1/libgcc.a(_umoddi3.o) to scan for pubtypes for objfile /Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes
Error connecting stdout and stderr (127.0.0.1:10001)
warning: .o file "/Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(monotouch-glue.x86.o)" more recent than executable timestamp in "/Users/drisszouak/Library/Application Support/iPhone Simulator/4.2/Applications/F902A6B1-4BA7-4BBE-B9D0-E5E4FE33A55A/ZenVelopes.app/ZenVelopes"
warning: Couldn't open object file '/Developer/MonoTouch/SDKs/MonoTouch.iphonesimulator.sdk/usr/lib/libmonotouch.a(monotouch-glue.x86.o)'
Attaching to process 3839.
Reading symbols for shared libraries . done
Reading symbols for shared libraries ...................................................................................................................... done
0x91880459 in read$UNIX2003 ()
  7 "WebThread"                     0x918750fa in mach_msg_trap ()
  6                                 0x918a30a6 in __semwait_signal ()
  5                                 0x91875136 in semaphore_wait_trap ()
  4                                 0x918750fa in mach_msg_trap ()
  3                                 0x9189aa12 in __workq_kernreturn ()
  2 "com.apple.libdispatch-manager" 0x9189b982 in kevent ()
* 1 "com.apple.main-thread"         0x91880459 in read$UNIX2003 ()

Thread 7 (process 3839):
#0  0x918750fa in mach_msg_trap ()
#1  0x91875867 in mach_msg ()
#2  0x00dfb4a6 in __CFRunLoopServiceMachPort ()
#3  0x00d58874 in __CFRunLoopRun ()
#4  0x00d58240 in CFRunLoopRunSpecific ()
#5  0x00d58161 in CFRunLoopRunInMode ()
#6  0x04f7e423 in RunWebThread ()
#7  0x918a285d in _pthread_start ()
#8  0x918a26e2 in thread_start ()

Thread 6 (process 3839):
#0  0x918a30a6 in __semwait_signal ()
#1  0x918ceee5 in nanosleep$UNIX2003 ()
#2  0x918cee23 in usleep$UNIX2003 ()
#3  0x002774e0 in monotouch_pump_gc ()
#4  0x918a285d in _pthread_start ()
#5  0x918a26e2 in thread_start ()

Thread 5 (process 3839):
#0  0x91875136 in semaphore_wait_trap ()
#1  0x0015b189 in finalizer_thread (unused=0x0) at ../../../../mono/metadata/gc.c:1026
#2  0x00203836 in start_wrapper (data=0x7b172e0) at ../../../../mono/metadata/threads.c:661
#3  0x00244c76 in thread_start_routine (args=0x8034a34) at ../../../../mono/io-layer/wthreads.c:286
#4  0x002746eb in GC_start_routine (arg=0x6ff8f60) at ../../../libgc/pthread_support.c:1390
#5  0x918a285d in _pthread_start ()
#6  0x918a26e2 in thread_start ()

Thread 4 (process 3839):
#0  0x918750fa in mach_msg_trap ()
#1  0x91875867 in mach_msg ()
#2  0x0011cfb2 in mach_exception_thread (arg=0x0) at ../../../../mono/mini/mini-darwin.c:138
#3  0x918a285d in _pthread_start ()
#4  0x918a26e2 in thread_start ()

Thread 3 (process 3839):
#0  0x9189aa12 in __workq_kernreturn ()
#1  0x9189afa8 in _pthread_wqthread ()
#2  0x9189abc6 in start_wqthread ()

Thread 2 (process 3839):
#0  0x9189b982 in kevent ()
#1  0x9189c09c in _dispatch_mgr_invoke ()
#2  0x9189b559 in _dispatch_queue_invoke ()
#3  0x9189b2fe in _dispatch_worker_thread2 ()
#4  0x9189ad81 in _pthread_wqthread ()
#5  0x9189abc6 in start_wqthread ()

Thread 1 (process 3839):
#0  0x91880459 in read$UNIX2003 ()
#1  0x000beb8b in mono_handle_native_sigsegv (signal=11, ctx=0xbfffd294) at ../../../../mono/mini/mini-exceptions.c:1826
#2  0x0000e7a6 in mono_sigsegv_signal_handler (_dummy=10, info=0xbfffd254, context=0xbfffd294) at ../../../../mono/mini/mini.c:4846
#3  <signal handler called>
#4  0x028d8a67 in objc_msgSend ()
#5  0x0cbabd70 in ?? ()
#6  0x01c721b5 in -[UIControl sendAction:to:forEvent:] ()
#7  0x01c74647 in -[UIControl(Internal) _sendActionsForEvents:withEvent:] ()
#8  0x01c731f4 in -[UIControl touchesEnded:withEvent:] ()
#9  0x01c080d1 in -[UIWindow _sendTouchesForEvent:] ()
#10 0x01be937a in -[UIApplication sendEvent:] ()
#11 0x01bee732 in _UIApplicationHandleEvent ()
#12 0x03eb9a36 in PurpleEventCallback ()
#13 0x00dfb064 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ ()
#14 0x00d5b6f7 in __CFRunLoopDoSource1 ()
#15 0x00d58983 in __CFRunLoopRun ()
#16 0x00d58240 in CFRunLoopRunSpecific ()
#17 0x00d58161 in CFRunLoopRunInMode ()
#18 0x03eb8268 in GSEventRunModal ()
#19 0x03eb832d in GSEventRun ()
#20 0x01bf242e in UIApplicationMain ()
#21 0x09e28c41 in ?? ()
#22 0x09e28b7a in ?? ()
#23 0x09e2857d in ?? ()
#24 0x09e284b9 in ?? ()
#25 0x09e28514 in ?? ()
#26 0x0000e56a in mono_jit_runtime_invoke (method=0x818564c, obj=0x0, params=0xbfffed6c, exc=0x0) at ../../../../mono/mini/mini.c:4733
#27 0x001c961b in mono_runtime_invoke (method=0x818564c, obj=0x0, params=0xbfffed6c, exc=0x0) at ../../../../mono/metadata/object.c:2615
#28 0x001cb2d7 in mono_runtime_exec_main (method=0x818564c, args=0x9e857f0, exc=0x0) at ../../../../mono/metadata/object.c:3581
#29 0x001cabfd in mono_runtime_run_main (method=0x818564c, argc=0, argv=0xbfffeea4, exc=0x0) at ../../../../mono/metadata/object.c:3355
#30 0x00095354 in mono_jit_exec (domain=0x6f91e58, assembly=0x6e1ce80, argc=1, argv=0xbfffeea0) at ../../../../mono/mini/driver.c:1094
#31 0x0027d299 in main ()

=================================================================
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.
=================================================================


Unhandled Exception: System.NullReferenceException: Object reference not set to an instance of an object
  at (wrapper managed-to-native) MonoTouch.UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
  at MonoTouch.UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Users/plasma/Source/iphone-3/monotouch/UIKit/UI开发者_开发知识库Application.cs:26 
  at MonoTouch.UIKit.UIApplication.Main (System.String[] args) [0x00000] in /Users/plasma/Source/iphone-3/monotouch/UIKit/UIApplication.cs:31 
  at ZenVelopes.Application.Main (System.String[] args) [0x00000] in /Users/drisszouak/Projects/ZenVelopes/ZenVelopes/Main.cs:14

You havn't provided enough context to tell you exactly what, but one of the objects you're sending an action message TO, likely the controller snippet you posted, has been collected.