When I try to build and run my keyboard extension, it sometimes just crashes with a Thread 1: signal SIGQUIT.
I am not able to reproduce the error. Sometimes I can build and run my app but most of the time the keyboard just quits. This happens on an actual device. In the simulator it does not open my keyboard and says Waiting to Attach.
The console does not output any errors at first. However, if I change the dropdown to View UI Hierachy in the Debug navigator I get the following description:
Details: No plist data for fetching view hierarchy: error evaluating expression “(id)[(Class)objc_getClass("DBGViewDebuggerSupport_iOS") fetchViewHierarchyWithOptions:(id)[(Class)objc_getClass("NSDictionary") dictionaryWithObjects:(id)[(id)[(id)[(Class)objc_getClass("NSArray") arrayWithObject:(id)[(Class)objc_getClass("NSNumber") numberWithBool:1]] arrayByAddingObject:(id)[(id)[(Class)objc_getClass("NSArray") arrayWithObject:#"_UIVisualEffectBackdropView"] arrayByAddingObject:#"_UIBackdropEffectView"]] arrayByAddingObject:(id)[(Class)objc_getClass("NSNumber") numberWithBool:0]] forKeys:(id)[(id)[(id)[(Class)objc_getClass("NSArray") arrayWithObject:#"DBGViewDebuggerUseLayersAsSnapshots"] arrayByAddingObject:#"DBGViewDebuggerEffectViewsToSnapshotAsImage"] arrayByAddingObject:#"DBGViewDebuggerAlwaysEncodeLayers"]]]”: error: Execution was interrupted, reason: EXC_BREAKPOINT (code=1, subcode=0x18daddc34).
The process has been returned to the state before expression evaluation.
Method: -[DBGAbstractViewDescriber handleFetchedViewInfo:fetchError:resultHandler:]
Please file a bug at http://bugreport.apple.com with this warning message and any useful information you can provide.
I also took a screenshot of the processes.
Am I doing something wrong and how could I prevent that my keyboard extension quits all the time when running it? Is it actually a bug as it says in the description?
DISCLAIMER
It seems like something in xCode 8.2.1 is broken and the debugger is not correctly attaching to the correct process or the hosting process is not properly loading the new code.
This is a not a permanent solution but a temporary workaround.
WORKAROUND
I have been able to work around this issue by following the steps below.
Kill any process that is using your keyboard (important!)
Launch the application using the debugger so the latest code is deployed to the device
Navigate to Settings > General > Keyboards > etc.
Remove your custom keyboard
Re-add your custom keyboard
Debug the application once again
The reason this works is because removing the keyboard kills the process that is hosting the extension allowing Xcode to attach to the new binary.
As I understand this is a bug in Xcode 8.2.1. because before update my custom keyboard was working very well.
this is a temporary solution.
Run your code like always!
Bring up your keyboard until the error (SIGQUIT) appear!
Goto xcode > debug > detach
Goto again Xcode > debug > Attach to Process: attach the keyboard (it should be first process)
now, your breakpoints will work. but there are no log output unfortunately! I hope it temporary solve your problem
It seems to me that whenever a Today Widget crashes for any reason it displays the "Unable to load" message (as on the attached screen).
When this happens nothing kicks off in the debugger, nothing appears on the Console. It seems to me like searching for a needle in the haystack. Is it possibl to debug the "Unable to load" message in Xcode in any way?
Xcode version: 8.2
iOS Simulator: 10.2
You can debug you Today Extension by doing the following:
With the application running in your device/simulator, open the widget. Then, when you have your widget open, go to Xcode->Debug->Attach to Process and you should find your widget name.
Note this will only work if you have your widget opened. You can set breakpoints and debug step by step to find out why the "Unable to Load" message appears.
You can simply select the widget's target in XCode and just run the project, and debug it as usual, with breakpoints, etc.
There is a catch: if the widget is already showing "Unable to load", then it means it crashed, and the debugging won't work.
What I found to be consistently working in restarting the widget is changing the device's language.
So, go to Settings -> General -> Change language
Then run your widget's target from XCode on that phone. Wait until the widgets page shows up and scroll down until your widget appears on the screen (that is when the widget gets loaded).
Even if it crashes now, you will see the crash in XCode.
I'm just getting started with Apple Watch. I found instructions from "Five Minute Watchkit", on getting the iOS app and the watch kit app both running in the simulator and both processes attached to the LLDB debugger.
What I do is launch and quit the iOS app to install a current version in the sim. Then I switch to the watchKit scheme and launch that, which displays my watch app UI on the watch simulator.
I then launch the corresponding iOS app in the simulator, then user "attach to process" in the Xcode menu to attach the debugger to the running iOS app.
This works. I can set breakpoints in either the watch kit InterfaceController or in my iOS app and the debugger breaks there when it should.
However, I'm not seeing NSLog() statements in the debug console from my iOS app. (I do see log statements from the WatchKit extension code.) If I set a breakpoint in my iOS app, it does stop at that breakpoint when it should. I assume the lack of console output from NSLog has SOMETHING to do with attaching to a running process on the sim rather than launching it from Xcode, but I don't know what that something is.
(BTW, attaching an action to a breakpoint that invokes NSLog from the breakpoint also doesn't display, but the "log message" debugger command DOES display.
Does anybody have any insights?)
EDIT:
The code in the iOS app doesn't seem to matter. In my case, it was a dirt simple IBAction that was attached to a button in the iOS app storyboard:
- (IBAction)buttonAction:(UIButton *)sender;
{
NSLog(#"Button clicked on iPhone");
}
I can set a breakpoint on that NSLog statement. The debugger stops at that line, but I don't see the log statement in the debug console.
I can reproduce that with a simple test app, sans WatchKit. The app consists of a NSTimer that prints "Timer fired" every second. (This code is 100% correct ;). Nothing shows in the log after I have manually attached to the process.
As far as I know NSLog outputs to stderr, I guess attaching the debugger does not redirect stderr to the Xcode terminal.
If you are okay with using the console app or the terminal to look at your logs you can do that. iOS8 stores simulator logs in ~/Library/Logs/CoreSimulator/<Device-UUID>. In this directory you will find a system.log, which contains all your NSLog output.
You can look at it in terminal (cat, grep, tail), or open it in the Console.app.
Apple confirms that (at least for GDB) in Technical Note TN2239: iOS Debugging Magic.
Console Output
Many programs, and indeed many system frameworks, print debugging
messages to stderr. The destination for this output is ultimately
controlled by the program: it can redirect stderr to whatever
destination it chooses. However, in most cases a program does not
redirect stderr, so the output goes to the default destination
inherited by the program from its launch environment. This is
typically one of the following:
If you launch a GUI application as it would be launched by a normal
user, the system redirects any messages printed on stderr to the
system log. You can view these messages using the techniques described
earlier.
If you run a program from within Xcode, you can see its
stderr output in Xcode's debugger Console window (choose the Console
menu item from the Run menu to see this window).
Attaching to a
running program (using Xcode's Attach to Process menu, or the attach
command in GDB) does not automatically connect the program's stderr to
your GDB window. You can do this from within GDB using the trick
described in the "Seeing stdout and stderr After Attaching" section of
Technical Note TN2030, 'GDB for MacsBug Veterans'.
The mentioned TN2030 is no longer available on their server (mirror). It showed how you can redirect stdout and stderr to the Xcode console. However, since shell tty isn't a valid command for LLDB it won't help much. But maybe there is a different way to access the tty Xcodes console uses, so I attach the important part of that TN.
Seeing stdout and stderr After Attaching
If you attach GDB to a process (as opposed to starting the process
from within GDB), you won't be able to see anything that the process
prints to stdout or stderr. Programs launched by the Finder typically
have stdout and stderr connected to "/dev/console", so the information
they print goes to the console. You can view this by launching the
Console application (in the Utilities folder), however, it's
inconvenient to have to look in a separate window. Another alternative
is to connect the process's stdout or stderr to the terminal device
for GDB's Terminal window. Listing 9 shows how to do this.
Listing 9. Connecting stdout and stderr to GDB's terminal device.
(gdb) attach 795
[... output omitted ...]
(gdb) call (void) DebugPrintMenuList()
No output )-:
Close the stdout and stderr file descriptors.
(gdb) call (void) close(1)
(gdb) call (void) close(2)
Determine the name of the terminal device for GDB itself.
(gdb) shell tty
/dev/ttyp1
Reopen stdout and stderr, but connected to GDB's terminal.
The function results should be 1 and 2; if not, something
is horribly wrong.
(gdb) call (int) open("/dev/ttyp1", 2, 0)
$1 = 1
(gdb) call (int) open("/dev/ttyp1", 2, 0)
$2 = 2
Try the DebugPrintMenuList again.
(gdb) call (void) DebugPrintMenuList()
Yay output!
Index MenuRef ID Title
----- ---------- ---- -----
<regular menus>
00001 0x767725D3 -21629 Ed
00002 0x76772627 1128 <Apple>
00003 0x767726CF 1129 File
00004 0x76772567 1130 Edit
[... remaining output omitted ...]
To add onto Filipp Keks answer, here's a visual representation of a much much simpler way to do it than the accepted answer.
From Filipp Keks's answer:
Plug in the device and open Xcode
Choose Window -> Devices from the menu bar
Under the DEVICES section in the left column, choose the device
To see the device console, click the up-triangle at the bottom left of the right hand panel
Click the down arrow on the bottom right to save the console as a file"
This screenshot was taken in Xcode 7.3.1 of the Devices window.
With Xcode Version 7.2 and iOS 9.2 etc, I found the following works:
Kill both the phone app and watch apps
Select the Watch Extension Target and hit Cmd+R (build and run)
Select the Phone target and hit Ctrl+Cmd+R (Run without building)
In my case, I have both apps up in their simulators and get NSLog output for both. I don't need to attach separately. Hope this helps.
https://developer.apple.com/library/ios/qa/qa1747/_index.html
Plug in the device and open Xcode
Choose Window -> Devices from the menu bar
Under the DEVICES section in the left column, choose the device
To see the device console, click the up-triangle at the bottom left of the right hand panel
Click the down arrow on the bottom right to save the console as a file
When your Provisioning profile is set to AdHoc or Distribution then Xcode doesnot show log, you need set development to view log
This might not solve showing up NSLog messages, but it might be helpful when debugging app started in background.
You can use the breakpoint feature that allows you to log messages.
The idea is to:
Create a breakpoint with "Automatically continue after evaluating actions" checked
add "Log message" action (you can also use expressions and print out values, for example: "Log message #variable#")
Attach debugger using anticipated process name (XCode will wait for the process to start)
Trigger app start.
Credits and details:
https://fluffy.es/how-to-debug-app-which-got-launched-push-notification/
In my case a set Automatically to see NSLog, before don't show at all
I came to this question, via this one (Xcode console empty after attaching to process) which is now closed.
My issue is that the debug console in Xcode is showing nothing (just an empty white box).
The solution for me is a tiny toggle at the bottom which changes between "variable view" and the actual debug console.
I have my iPhone emulator opened not from xCode environment, and I have my application installed on it. In my application I use NSLog to print messages to console.
How can I open a console view for the emulator so I can see the messages printed by the application?
It's simple.
iOS Simluator > Debug Menu > Open System Log.
or Press 'Command + /'
Voila! You would be able to see all your logs now.
I have a monodroid application that terminates without any notice. When it hits an exception the application just terminates. It was deployed to the device using "Start without debugging" from Visual Studio. When I run it with the debugger in visual studio I do get a break on an exception. Is this normal behaviour for the application to just terminate?
Yes, this sounds perfectly normal. If your application encounters an unhandled exception it will crash, terminating completely. You can take a look at the Android Debug Log to see a log of what happened, including the stacktrace produced from any crashes of the application.