ios - built_products_dir - xcode环境变量




如何设置CG_CONTEXT_SHOW_BACKTRACE环境变量? (3)

在我看来,我有三个按钮。 在viewDidLoad()中设置cornerRadus之后: button.layer.cornerRadius = 20 我在日志中收到以下错误消息:

 <Error>: CGContextSaveGState: invalid context 0x0. 
If you want to see the backtrace, please set 
CG_CONTEXT_SHOW_BACKTRACE environmental variable.

问题:

  • 如何设置CG_CONTEXT_SHOW_BACKTRACE环境变量?
  • 或者我该如何修复此警告?

好的,我现在从消息中回溯了。 这对我没有任何意义。 一些帮助请...

Aug  7 14:27:00  <Error>: CGContextSaveGState: invalid context 0x0. Backtrace:
      <-[UIStatusBarItemView updateContentsAndWidth]+33>
       <-[UIStatusBarItemView initWithItem:data:actions:style:]+477>
        <+[UIStatusBarItemView createViewForItem:withData:actions:foregroundStyle:]+134>
         <-[UIStatusBarLayoutManager _createViewForItem:withData:actions:]+163>
          <-[UIStatusBarLayoutManager _prepareEnabledItemType:withEnabledItems:withData:actions:itemAppearing:itemDisappearing:]+36
           <-[UIStatusBarLayoutManager prepareEnabledItems:withData:actions:]+92>
            <-[UIStatusBarForegroundView _setStatusBarData:actions:animated:]+797>
             <-[UIStatusBarForegroundView setStatusBarData:actions:animated:]+332>
              <__51-[UIStatusBar _prepareToSetStyle:animation:forced:]_block_invoke+360>
               <+[UIView(Animation) performWithoutAnimation:]+65>
                <-[UIStatusBar _prepareToSetStyle:animation:forced:]+866>
                 <-[UIStatusBar _requestStyleAttributes:animationParameters:forced:]+391>
                  <-[UIStatusBar requestStyle:animationParameters:forced:]+437>
                   <-[UIStatusBar requestStyle:animated:forced:]+90>
                    <-[UIStatusBar _evaluateServerRegistration]+250>
                     <__45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke+590>
                      <-[UIView(Hierarchy) _postMovedFromSuperview:]+544>
                       <-[UIView(Internal) _addSubview:positioned:relativeTo:]+1967>
                        <-[UIStatusBarWindow setStatusBar:]+288>
                         <-[UIApplication _createStatusBarWithRequestedStyle:orientation:hidden:]+340>
                          <-[UIApplication _runWithMainScene:transitionContext:completion:]+950>
                           <-[UIApplication workspaceDidEndTransaction:]+188>
                            <-[FBSSerialQueue _performNext]+192>
                             <-[FBSSerialQueue _performNextFromRunLoopSource]+45>
                              <__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__+17>
                               <__CFRunLoopDoSources0+556>
                                <__CFRunLoopRun+867>
                                 <CFRunLoopRunSpecific+488>
                                  <-[UIApplication _run]+402>
                                   <UIApplicationMain+171>
                                    <main+117>



Aug  7 14:27:00  <Error>: CGContextTranslateCTM: invalid context 0x0. Backtrace:
      <-[UIStatusBarItemView updateContentsAndWidth]+33>
       <-[UIStatusBarItemView initWithItem:data:actions:style:]+477>
        <+[UIStatusBarItemView createViewForItem:withData:actions:foregroundStyle:]+134>
         <-[UIStatusBarLayoutManager _createViewForItem:withData:actions:]+163>
          <-[UIStatusBarLayoutManager _prepareEnabledItemType:withEnabledItems:withData:actions:itemAppearing:itemDisappearing:]+36
           <-[UIStatusBarLayoutManager prepareEnabledItems:withData:actions:]+92>
            <-[UIStatusBarForegroundView _setStatusBarData:actions:animated:]+797>
             <-[UIStatusBarForegroundView setStatusBarData:actions:animated:]+332>
              <__51-[UIStatusBar _prepareToSetStyle:animation:forced:]_block_invoke+360>
               <+[UIView(Animation) performWithoutAnimation:]+65>
                <-[UIStatusBar _prepareToSetStyle:animation:forced:]+866>
                 <-[UIStatusBar _requestStyleAttributes:animationParameters:forced:]+391>
                  <-[UIStatusBar requestStyle:animationParameters:forced:]+437>
                   <-[UIStatusBar requestStyle:animated:forced:]+90>
                    <-[UIStatusBar _evaluateServerRegistration]+250>
                     <__45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke+590>
                      <-[UIView(Hierarchy) _postMovedFromSuperview:]+544>
                       <-[UIView(Internal) _addSubview:positioned:relativeTo:]+1967>
                        <-[UIStatusBarWindow setStatusBar:]+288>
                         <-[UIApplication _createStatusBarWithRequestedStyle:orientation:hidden:]+340>
                          <-[UIApplication _runWithMainScene:transitionContext:completion:]+950>
                           <-[UIApplication workspaceDidEndTransaction:]+188>
                            <-[FBSSerialQueue _performNext]+192>
                             <-[FBSSerialQueue _performNextFromRunLoopSource]+45>
                              <__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__+17>
                               <__CFRunLoopDoSources0+556>
                                <__CFRunLoopRun+867>
                                 <CFRunLoopRunSpecific+488>
                                  <-[UIApplication _run]+402>
                                   <UIApplicationMain+171>
                                    <main+117>




Aug  7 14:27:00 <Error>: CGContextRestoreGState: invalid context 0x0. Backtrace:
      <-[UIStatusBarItemView updateContentsAndWidth]+33>
       <-[UIStatusBarItemView initWithItem:data:actions:style:]+477>
        <+[UIStatusBarItemView createViewForItem:withData:actions:foregroundStyle:]+134>
         <-[UIStatusBarLayoutManager _createViewForItem:withData:actions:]+163>
          <-[UIStatusBarLayoutManager _prepareEnabledItemType:withEnabledItems:withData:actions:itemAppearing:itemDisappearing:]+36
           <-[UIStatusBarLayoutManager prepareEnabledItems:withData:actions:]+92>
            <-[UIStatusBarForegroundView _setStatusBarData:actions:animated:]+797>
             <-[UIStatusBarForegroundView setStatusBarData:actions:animated:]+332>
              <__51-[UIStatusBar _prepareToSetStyle:animation:forced:]_block_invoke+360>
               <+[UIView(Animation) performWithoutAnimation:]+65>
                <-[UIStatusBar _prepareToSetStyle:animation:forced:]+866>
                 <-[UIStatusBar _requestStyleAttributes:animationParameters:forced:]+391>
                  <-[UIStatusBar requestStyle:animationParameters:forced:]+437>
                   <-[UIStatusBar requestStyle:animated:forced:]+90>
                    <-[UIStatusBar _evaluateServerRegistration]+250>
                     <__45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke+590>
                      <-[UIView(Hierarchy) _postMovedFromSuperview:]+544>
                       <-[UIView(Internal) _addSubview:positioned:relativeTo:]+1967>
                        <-[UIStatusBarWindow setStatusBar:]+288>
                         <-[UIApplication _createStatusBarWithRequestedStyle:orientation:hidden:]+340>
                          <-[UIApplication _runWithMainScene:transitionContext:completion:]+950>
                           <-[UIApplication workspaceDidEndTransaction:]+188>
                            <-[FBSSerialQueue _performNext]+192>
                             <-[FBSSerialQueue _performNextFromRunLoopSource]+45>
                              <__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__+17>
                               <__CFRunLoopDoSources0+556>
                                <__CFRunLoopRun+867>
                                 <CFRunLoopRunSpecific+488>
                                  <-[UIApplication _run]+402>
                                   <UIApplicationMain+171>
                                    <main+117>

在Xcode 7上:

如果您仍希望隐藏状态栏,只需将 Info.plist 文件中的 UIViewControllerBasedStatusBarAppearance 更改 View controller-based status bar appearance 。 不要忘记用 NO 设置它


您可以通过此菜单设置环境变量:Product - > Scheme - > Edit Scheme。 在“运行”项下,找到“参数”选项卡,您将在选项卡中看到“环境变量”,添加 CG_CONTEXT_SHOW_BACKTRACE 并将其值设置为YES。








core-graphics