Invalid context 0x0. This is a serious error.

[conanjb]

Hi,

I've been using RSColorPicker in my app for a while.

I just updated to XCode51-DP2 and the 7.1 beta and I am getting the errors below when I access RSColorPicker in my app.

Just to be sure I ran the standalone RSColorPicker example project and I also got the same errors.

RSColorPicker[20655] : CGContextAddPath: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. RSColorPicker[20655] : clip: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.

These errors seem to prevent the app from continuing.

jb

[RSully]

Could you provide anymore of a backtrace from Xcode? Trying to see if this is an issue in our code or within the bitmap library.

[conanjb]

Hi,
  I wish I could, but the app just basically stalls and these error
  messages just continue to be written to the debug console. There's
  no crash where I can get a backtrace. And pausing on execution
  from Xcode doesn't help either.
  It works great in 7.0 and the current stable Xcode. This issue is
  only in the beta version.
  On 12/16/13, 7:51 AM, Ryan wrote:

  Could you provide anymore of a backtrace from Xcode? Trying to
    see if this is an issue in our code or within the bitmap
    library. 
  —
    Reply to this email directly or view
      it on GitHub.

-- 
     Gary 'JB' Baranzini , MS, L.Ac.,
        CMTconanjb@gmail.comIn Balance
          Acupuncture925.998.4768 or
        209.221.0122

[RSully]

Right, but based on the error messages you shared this issue is being "upgraded" from silent/warning to an error. We need to look into this before 7.1 goes live.

/cc @unixpickle

[conanjb]

That's why I brought it to your
  attention. 
  It's not a very helper error message, is it? I Google it and some
  other have encountered this also. Seems to be in the CG area.
  Good luck finding it.
  On 12/16/13, 8:00 AM, Ryan wrote:

  Right, but based on the error messages you shared this issue is
    being "upgraded" from silent/warning to an error. We need to
    look into this before 7.1 goes live. 
  /cc @unixpickle
  —
    Reply to this email directly or view
      it on GitHub.

-- 
     Gary 'JB' Baranzini , MS, L.Ac.,
        CMTconanjb@gmail.comIn Balance
          Acupuncture925.998.4768 or
        209.221.0122

[unixpickle]

The problem is in the custom slider.

- (CGRect)trackRectForBounds:(CGRect)bounds {
    //to hide the track view
    return CGRectMake(0, ceilf(bounds.size.height / 2), bounds.size.width, 0);
}

This was never really supported by apple in the first place.

[conanjb]

Yes, commenting out the two occurrences resolves the issue. Is that the correct solution?

[unixpickle]

Yes. Really, the correct solution is to use your own sliders. These are just demos of how one might control the brightness and opacity of an RSColorPicker.

[RSully]

If this happens again from another cause please make a new issue.