I use Vuforia SDK, version 6.2.9 in my iOS App. All work's fine, but there is an error when the app enter from background. The viewcontroller running VUFORIA is listening for UIApplicationWillResignActiveNotification and UIApplicationDidBecomeActiveNotification notifications. In the case of UIApplicationWillResignActiveNotification pause AR, in the case of UIApplicationDidBecomeActiveNotification resume AR.
// we use the iOS notification to pause/resume the AR when the application goes (or come back from) background [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(pauseAR) name:UIApplicationWillResignActiveNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resumeAR) name:UIApplicationDidBecomeActiveNotification object:nil];
These are the methods
- (void) pauseAR { NSError * error = nil; if (![vapp pauseAR:&error]) { NSLog(@"Error pausing AR:%@", [error description]); } }
- (void) resumeAR {
NSError * error = nil; if(! [vapp resumeAR:&error]) { NSLog(@"Error resuming AR:%@", [error description]); }
// on resume, we reset the flash Vuforia::CameraDevice::getInstance().setFlashTorchMode(false);
[self handleRotation:self.interfaceOrientation]; }
When I return to the scan mode, after the app has entered from background, the camera is frozen, with error
Could not find a UIView with CAEAGLLayer or CAMetalLayer layer class that responds to selector renderFrameVuforia
2017-07-17 11:13:01.187406+0200 App[8689:2961061] frame: {{0, 0}, {375, 667}} 2017-07-17 11:13:01.243707+0200 App[8689:2961061] DEBUG/AR(8689) Could not find a UIView with CAEAGLLayer or CAMetalLayer layer class that responds to selector renderFrameVuforia 2017-07-17 11:13:01.253958+0200 App[8689:2961061] Vuforia Library version 6.2.9 2017-07-17 11:13:01.731099+0200 App[8689:2961061] AR View: Rotating to Portrait 2017-07-17 11:13:01.731406+0200 App[8689:2961061] frame: {{0, 0}, {375, 667}} 2017-07-17 11:13:01.731562+0200 App[8689:2961061] VideoBackgroundConfig: size: 750,1334 2017-07-17 11:13:01.731589+0200 App[8689:2961061] VideoMode:w=1280 h=720 2017-07-17 11:13:01.731611+0200 App[8689:2961061] width=750.000 height=1334.000 2017-07-17 11:13:01.731638+0200 App[8689:2961061] ViewPort: X,Y: 0,0 Size X,Y:750,1334 2017-07-17 11:13:02.598959+0200 App[8689:2962160] INFO/AR(8689) 2017-07-18 11:13:02: Completed CloudReco transaction with ID '6f5c61ecc07741a7b652242abf909479' 2017-07-17 11:13:02.843834+0200 App[8689:2961061] frame: {{0, 0}, {375, 667}} 2017-07-17 11:13:02.844215+0200 App[8689:2961061] frame: {{0, 0}, {375, 667}} 2017-07-17 11:13:02.860971+0200 App[8689:2961061] DEBUG/AR(8689) UIView has CAEAGLLayer layer class 2017-07-17 11:13:02.861114+0200 App[8689:2961061] DEBUG/AR(8689) UIView does not respond to selector renderFrameVuforia 2017-07-17 11:13:02.861191+0200 App[8689:2961061] DEBUG/AR(8689) UIView has CAEAGLLayer layer class 2017-07-17 11:13:02.861222+0200 App[8689:2961061] DEBUG/AR(8689) UIView does not respond to selector renderFrameVuforia
Thanks for your help!