[iOS 12] App doesn't start when debugging (icon left greyed out)

[bradumbaugh]

Steps to Reproduce

1. Create a new single view iOS app (using Xamarin's Xcode 10 beta 6 preview for VSMac)
2. Debug on simulator (I've repro'd on an iPhone X simulator running iOS 12, an iPhone 8 simulator running iOS 12, and an iPhone SE running iOS 12)
3. If the app launches successfully, stop the debugging session and delete the app manually
4. Debug app again
5. Sooner or later the app will get into a state where it is installed, but the icon is greyed out; the app never starts

Expected Behavior

App should start and debug

Actual Behavior

App does not start / debug. Icon is left greyed out.

Environment

Visual Studio Enterprise 2017 for Mac
Version 7.6.1 (build 7)
Installation UUID: 623d8c09-02dc-4241-ad34-5c29ea2d12f7
Runtime:
Mono 5.12.0.305 (2018-02/e0e035e3b14) (64-bit)
GTK+ 2.24.23 (Raleigh theme)
Xamarin.Mac 4.4.1.178 (master / eeaeb7e)

Package version: 512000305

NuGet
Version: 4.3.1.4445

.NET Core
Runtime: /usr/local/share/dotnet/dotnet
Runtime Versions:
2.1.2
2.1.1
2.0.5
2.0.3
SDK: /usr/local/share/dotnet/sdk/2.1.302/Sdks
SDK Versions:
2.1.302
2.1.301
2.1.4
2.0.3
MSBuild SDKs: /Library/Frameworks/Mono.framework/Versions/5.12.0/lib/mono/msbuild/15.0/bin/Sdks

Xamarin.Profiler
Version: 1.6.3
Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler

Apple Developer Tools
Xcode 10.0 (14320.12.2)
Build 10L232m

Xamarin.Mac
Version: 4.99.3.658 (Visual Studio Enterprise)
Hash: 1eefd4e
Branch:
Build date: 2018-08-21 15:01:53-0400

Xamarin.iOS
Version: 11.99.3.538 (Visual Studio Enterprise)
Hash: 1eefd4e
Branch: HEAD
Build date: 2018-08-21 15:01:52-0400

Xamarin.Android
Version: 9.0.0.18 (Visual Studio Enterprise)
Android SDK: /Users/bradumbaugh/Library/Developer/Xamarin/android-sdk-macosx
Supported Android versions:
2.3 (API level 10)
4.0.3 (API level 15)
4.2 (API level 17)
4.4 (API level 19)
5.0 (API level 21)
6.0 (API level 23)
7.0 (API level 24)
7.1 (API level 25)
8.1 (API level 27)

SDK Tools Version: 26.1.1
SDK Platform Tools Version: 28.0.0
SDK Build Tools Version: 28.0.0

Java SDK: /usr
java version "1.8.0_131"
Java(TM) SE Runtime Environment (build 1.8.0_131-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.131-b11, mixed mode)

Android Designer EPL code available here:
https://github.com/xamarin/AndroidDesigner.EPL

Xamarin Inspector
Version: 1.4.3
Hash: db27525
Branch: 1.4-release
Build date: Mon, 09 Jul 2018 21:20:18 GMT
Client compatibility: 1

Build Information
Release ID: 706010007
Git revision: 7c9e755fe667840f2eed42b2e7910ec18ef51b82
Build date: 2018-08-24 02:25:33+00
Build branch: release-7.6-xcode10
Xamarin extensions: 1196f085605a84ce99f390a1aaee0bf257d31a50

Operating System
Mac OS X 10.13.6
Darwin 17.7.0 Darwin Kernel Version 17.7.0
Thu Jun 21 22:53:14 PDT 2018
root:xnu-4570.71.2~1/RELEASE_X86_64 x86_64

Enabled user installed extensions
MonoGame Extension 3.7.0.1
Vim 0.61.0
Internet of Things (IoT) development (Preview) 7.5.3

Build Logs

• IDE log after this happened with a new project:
  Ide.2018-08-28__15-57-46.log

• IDE log (looks a little more helpful) after another project I have where I noticed this:
  Ide.log

Example Project (If Possible)

I've been able to repeat this with a new iOS single view app

[mandel-macaque]

I have managed to reproduce this on a sim with the current Xcode 10 branch. The following are the device logs of the sim when this occurs:

https://gist.github.com/mandel-macaque/fd3030b8d0e7ecd2f5dce5eb05cc8ddb

Interestingly, reseting the sim makes the issue not happen.

[mandel-macaque]

Verbose output of mlaunch -> https://gist.github.com/mandel-macaque/9c60514ddfba8afda29974d87debe7bd

[mandel-macaque]

Rebooting does not fix the issue, resetting apparently does. I find it easier to reproduce in the iPhone 8 sim than in the iPhone X

[mandel-macaque]

System.log of the failing simulator:

system.log

And the CoreSimulator.log (do remember, the failing sim is the iPhone 8 one).

CoreSimulator.log

[mandel-macaque]

Running mlaunch manually to a diff sim shows the following: https://gist.github.com/mandel-macaque/2b922a83f2d6fb17a0dc238d663fc291

[spouliot]

If I understand correctly it sounds like there's two issues here

1. the app does not get installed and log shows

error HE0046: Failed to install the app 'com.xamarin.TestLaunchSim' on the device 'iOS 12.0 (16A5354b) - iPhone 8': This app could not be installed at this time.

2. the IDE state is incorrect, i.e. greyed button but no mention of the error from mlaunch. IOW an error should be reported to the user and it IDE should be able to try again.

@mandel-macaque if that's right please split the issue in two and tag the new one on vs4m so they can fix the reporting/retry from the IDE.

As for the first part let's see if this is a new issue (does it work on stable) or something uncommon/misdiagnosed before (and set milestone accordingly).

[bradumbaugh]

@spouliot I've not seen the IDE button in an incorrect state; it's the app icon on the simulator that is greyed out.

[bradumbaugh]

@mandel-macaque I just recreated this issue locally using the iPhone 6s iOS 12 simulator. Uninstalled the app, then did Erase All Content and Settings... on the simulator. First run worked fine after that, but then the subsequent one failed again.

[bradumbaugh]

Unsure if this is related, but I'll add it here for completeness. Working with @mandel-macaque I also tried switching to stable and debugging a blank single view app on the iPhone X 11.4 Simulator. First time it worked fine, second time I got a "waiting for debugger to connect" message that never went away. Then I did Erase Content and Settings... on the simulator and was unable to reproduce afterwards. I believe @mandel-macaque saw similar symptoms.

[mandel-macaque]

I have re-tested this on Xcode10 (final) and rather that getting a grey app, the app does not longer get installed.

[mandel-macaque]

To be clear, this bug only happens when you create the application, debug it and later manually deleted. When you try to re-debug it the application won't be installed. The workaround is to reset the simulator and everything will work as expected.

[MathieuJack]

Having the same issue. First reseting simulator was fixing problem for a while, but now even after reseting first deploy gets bad (grey icon). Using Visual Studio 2019 for Mac v8.2.6 (build 26)
Tip : When deploying using VS 2019 on PC (remotly connected to Mac), then app could be successfully installed on simulator.