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iOS

Posted by Jerome Garot
Jerome Garot
2,886 Points

*** Terminating app due to uncaught exception 'NSInvalidArgumentException' - Game Related

Hey all,

I've been slowly making my own game with what I've learned from the SpaceCat game.

I've run into something rather troublesome and I can't seem to figure out, I've been moving slowly and checking my code as I go along to ensure I don't lose track of where things mess up.

So I've come to the point where I'm trying to take lives off, just wanted to test the minusing and I get a crash and notification:

ShapeGame[23421:8375806] -[HudNode loseLives]: unrecognized selector sent to instance 0x7fe0aa526a90
2014-10-30 22:05:34.903 ShapeGame[23421:8375806] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[HudNode loseLives]: unrecognized selector sent to instance 0x7fe0aa526a90'
*** First throw call stack:
(
    0   CoreFoundation                      0x0000000101ba3f35 __exceptionPreprocess + 165
    1   libobjc.A.dylib                     0x000000010183cbb7 objc_exception_throw + 45
    2   CoreFoundation                      0x0000000101bab04d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
    3   CoreFoundation                      0x0000000101b0327c ___forwarding___ + 988
    4   CoreFoundation                      0x0000000101b02e18 _CF_forwarding_prep_0 + 120
    5   ShapeGame                        0x0000000101305bc8 -[GamePlayScene didBeginContact:] + 5144
    6   PhysicsKit                          0x00000001056c818b _ZN17PKContactListener13flushContactsEv + 341
    7   PhysicsKit                          0x00000001056c5e88 -[PKPhysicsWorld stepWithTime:velocityIterations:positionIterations:] + 174
    8   SpriteKit                           0x00000001021dbcfb -[SKScene _update:] + 2366
    9   SpriteKit                           0x00000001021f5949 -[SKView(Private) _update:] + 563
    10  SpriteKit                           0x00000001021f32d9 -[SKView renderCallback:shouldBlock:] + 837
    11  SpriteKit                           0x00000001021f0391 __29-[SKView setUpRenderCallback]_block_invoke + 56
    12  SpriteKit                           0x000000010221cdf4 -[SKDisplayLink _callbackForNextFrame:] + 256
    13  QuartzCore                          0x00000001068ad747 _ZN2CA7Display15DisplayLinkItem8dispatchEv + 37
    14  QuartzCore                          0x00000001068ad60f _ZN2CA7Display11DisplayLink14dispatch_itemsEyyy + 315
    15  CoreFoundation                      0x0000000101b0bf64 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
    16  CoreFoundation                      0x0000000101b0bb25 __CFRunLoopDoTimer + 1045
    17  CoreFoundation                      0x0000000101acee5d __CFRunLoopRun + 1901
    18  CoreFoundation                      0x0000000101ace486 CFRunLoopRunSpecific + 470
    19  GraphicsServices                    0x00000001084169f0 GSEventRunModal + 161
    20  UIKit                               0x0000000102389420 UIApplicationMain + 1282
    21  ShapeGame                        0x0000000101309683 main + 115
    22  libdyld.dylib                       0x000000010452c145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException

I know exactly where it's coming from, right here:

-(void) loseLives {
    if (self.lives > 0) {
        self.lives--;
    }

}

The area from where I'm calling it from has not shown any problems with my other methods for adding score or anything like that.

Other successful method:

-(void) addPoints:(NSInteger) points {
    self.score += points;

    SKLabelNode *scoreLabel = (SKLabelNode *)[self childNodeWithName:@"Score"];

    scoreLabel.text = [NSString stringWithFormat:@"%ld", self.score];
}

Area from where I'm calling it:

else if (firstBody.categoryBitMask == CollisionCategoryShape && secondBody.categoryBitMask == CollisionCategoryFloor) {
        ShapeNode *shape = (ShapeNode *)firstBody.node;
        HudNode *hud = [self childNodeWithName:@"HUD"];

            if (shape.shapeType == RoundShape) {
                [hud addPoints]; // No Problem
            } else {
                [hud loseLives];
            }

It is defined in the header file, same as lives and points.

Everything seems just like addPoints, I just don't know why it does this.

UPDATE: I found the problem, it was in the if statement.

    // This for some reason works....
    NSInteger currentLives = self.lives;

    if (currentLives > 0) {
        self.lives--;
    }

    // But this doesn't
    if (self.lives > 0) {
        self.lives--;
    }

Can anyone tell me why this is?