How to solve CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [nan nan]?

Question

I have an error where it crash the application when it is starting up. This is the error that i got:

*** Terminating app due to uncaught exception 'CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [nan nan]'
*** First throw call stack:
(0x250b022 0x2709cd6 0x24b3a48 0x24b39b9 0x217ec0d 0x2174f55 0x158f3f7 0xbc74e 0xbe512 0xbfa26 0xbe4ad 0x224ffda 0x224f956 0x224e449 0x224ab9a 0x24df970 0x247f1c1 0x2442967 0x2441d84 0x2441c9b 0x2c0a7d8 0x2c0a88a 0x1559626 0x2aed 0x2a65)
terminate called throwing an exception

i tried using Exception breakpoint and it doesn't show which part of the code has gone wrong.It only stop at this point -0xbc74e: movl $0, %eax-

How can i solve it? Please help.

*edit

I found the part which throws the exception but i can't see what is wrong

- (void)viewDidLoad {
[super viewDidLoad];
[self.activityView startAnimating];
self.mapView.layerDelegate = self;
self.mapView.touchDelegate = self;
self.mapView.calloutDelegate = self;

NSURL *mapUrl = [NSURL URLWithString:kTiledMapServiceURL];
AGSTiledMapServiceLayer *tiledLyr = [AGSTiledMapServiceLayer tiledMapServiceLayerWithURL:mapUrl];
[self.mapView addMapLayer:tiledLyr withName:@"Tiled Layer"];
        .
        .
        .
}
- (void)mapViewDidLoad:(AGSMapView *)mapView {

AGSEnvelope *envelope = [[AGSEnvelope alloc]initWithXmin:29757.610204117 ymin:40055.0379682464 xmax:29884.6992302249 ymax:40236.6028660071 spatialReference:self.mapView.spatialReference];

//call method to set extent, pass in envelope
[self.mapView zoomToEnvelope:envelope animated:YES];

self.mapView.callout.width = 195.0f;
self.mapView.callout.accessoryButtonHidden = YES;

[self.mapView.gps start];
[self.mapView centerAtPoint:self.mapView.gps.currentPoint animated:YES];  

[self.activityView stopAnimating];
self.activityView.hidden = YES;

}

This line is causing the error self.mapView.layerDelegate = self; which by default call the method mapViewDidLoad

Answer 1

I think this error occurs because the layer which is executed has frame in this form:

Layer frame == {{inf, inf}, {0, 0}}

Here inf is infimum. Its set of numbers.

So the solution to avoid this kind of issue just create condition before return of layer. Like as:

if (layer.frame.size.width ==0 || layer.frame.size.height ==0 ) {
    return [self simpleLayer];
}else{
    return layer;        
} 

Where simple layer is like as :

-(CALayer *)simpleLayer{
    CALayer *layer = [[CALayer alloc] init];
    [layer setFrame:CGRectMake(0, 0, 10, 10)];
    [layer setHidden:TRUE];
    return layer;
}

This condition solved my issue. Try it.