How to fix a triggered Zombie tracking bug in ShinobiCharts?


Below is a crash that we are seeing. It occurs between a ViewWillAppear and ViewDidAppear for a view with two Shinobi charts. 

SChartDateFrequency object to negative or zero - a default of 1 has been set.

From: SChartDateFrequency = { Y=2147483647, M=2147483647, W=2147483647, D=2147483647, h=2147483647, m=2147483647, s=1 }

2014-06-07 20:00:53.066 Velocity Ultimate[2741:60b] -[__NSCFNumber length]: unrecognized selector sent to instance 0x15e55330

When we turn on Zombie tracking we see this: 

2014-06-08 09:45:28.043 Velocity Ultimate[3347:60b] *** -[CFNumber compare:]: message sent to deallocated instance 0x178eb2b0

The crash trace looks like this:

0 objc_msgSend
1 - [SChartDataLoader updateUserXMin:userXMax:userYMin:userYMax:fromUserX:userY;]
2 - [SChartDataLoader configureXAxis:yAxis:withUserData:]

When we use the zombie instruments tool in XCode - the App stops crashing.  

Where should we look in our Shinobi code to prevent this deallocation error?



Hi gillammi,

Thanks for getting in touch!

Is it possible for you to manipulate one of our sample apps that reproduces your issue and send it to us at

If you could also send the following information that would be helpful:

  • ShinobiCharts version number.
  • iOS versions & devices your issue occurs on.

This would really help us identify the source of the issue.

Kind Regards,
Andrew Polkinghorn