App crashes playing video in background on iOS

Bug Reports
1

Fuse version 0.23.0 (build 7041) OS X El Capitan Version 10.11.6

Running the “Video Login Screen Fuse Example” in Background audio mode causes App to crash.

Steps

  1. Download example project - Download and extract Zip from: https://github.com/yupferris/fuse-example-video-login-screen/tree/master
  2. Download video with sound - Download and extract Zip of Graham Uhelski’s “The Valley” (you need a video with audio - the original video appears to be silent) from: http://mazwai.com/#/videos/220 2a. Copy the video (thevalleygrahamuheslkimp4.mp4) into the assets folder
  3. Edit MainView.ux 3a. On Line 31 - Change “nature.mp4” to “thevalleygrahamuheslkimp4.mp4” 3b. Save
    1. Preview on iOS - (I’m using Atom, so I right-click on the code and choose: “Fuse preview - iOS”)
    2. Turn on Background Audio - In Xcode (using 7.3.1), go to the “Capabilities” tab, turn on “Background Modes” and check: “Audio, Airplay and Picture in Picture” (next to “Modes:”)
    3. Run on iPhone - In Xcode, ensure your iPhone is plugged in and the active scheme is set to run on your iPhone and click the run button.
    4. Wait for sound - once the app is running, wait until you can hear sound from your iPhone.
    5. Press the iPhone’s On/Off button. 8a. You should continue to hear the videos music coming from your iPhone. If not, go back to step 5.
    6. Count to 3
    7. Press the iPhone’s Home Button
    8. Crashes - the app crashes with “Thread 1: EXC_BAD_ACCESS (code=1, address=0x1)” in Fuse.Controls.Native.iOS.GraphicsView.mm
void GraphicsView::EndDraw(uObject* handle)
{
    uStackFrame __("Fuse.Controls.Native.iOS.GraphicsView", "EndDraw(ObjC.Object)");
    @autoreleasepool
    {
        [] (::id handle) -> void
        {
            ::GLKView* glkView = (::GLKView*)handle;
            [glkView display];                       // <-- Thread 1: EXC_BAD_ACCESS (code=1, address=0x1)
        } (::g::ObjC::Helpers::GetHandle(handle));

    }

}
2

Don’t know how display is declared, but possibly it needs to be (strong, nonatomic)?

3

Hi!

Thanks for your report. I have filed an internal ticket for this issue. display is a method on GLKView, if this happens while the app is in the background I have an inkling that GLKView is touching resources it shouldnt when display is called. Kinda makes sense since the app is in the background

4

Is it possible to get an approximate date when this should be resolved?

5

Hi!

The fix is included in the upcoming release. Also, it is live now in the pre-release at https://www.fusetools.com/downloads/channel/qa.

6

Thanks Vegard - that seems to have done it!

From time-to-time I’m getting a libsystem_kernel.dylib`mach_msg_trap when returning form background mode after the app has been interrupted while in background by another audio stream - like Siri. But when I build for release, it doesn’t seem to happen so the issue might be with live-reload.

7

Thanks Vegard, the last pre-release solve a really nasty bug which was crashing my app, related to display and GLKView. It seems to work perfect now, thanks!