<error>: Cgcontextrestoregstate:invalid context 0x0. If you want to see the backtrace, please set cg_context_show_backtrace environmental variable.

turn from here Error Reason: Set the app's status bar style using the old way, in Info.plist set the view controller-based status bar appearance is no, the default is yes, The general type of iOS6 use this way, ios7,8 is also compatible, but to the iOS9 to report a warning. Modify the mode to set the view controller-based status bar appearance to Yes, and then use the new way to implement the style of the status bar. the method after iOS7

• -(Uistatusbarstyle) Preferredstatusbarstyle;

• -(Uiviewcontroller *) Childviewcontrollerforstatusbarstyle;

• -(void) setneedsstatusbarappearanceupdate

<error>: Cgcontextrestoregstate:invalid context 0x0. If you want to see the backtrace, please set cg_context_show_backtrace environmental variable.