Android Logcat is empty when debug with device in android studio

Question

When I try to debug using android device in android studio Logcat shows nothing. But when I use emulator LogCat shows all the messages. How should view the Logcat messages w

Answer 1

I understand that this question is over 2 years old, but from my searches a few people are still having a persistent problem with this. One possible solution to this (which worked for me after two hours!) is that your phone settings may have its "Log Switch" set to off, hence it isn't sending your log data to the IDE.

Here is the solution - "Unable to open log device '/dev/log/main': No such file or directory"

Hope it helps!

Answer 2

In Android studio 0.8.0 you should enable ADB integration through Tools -> Android, before run your app. Then the log cat will work correctly. Notice that if you make ADB integration disabled while your app is running and again make it enable, then the log cat dosen't show anything unless you rebuild your project.

Answer 3

Restart the phone. And it solves magically

I was using Lenovo A7000plus powered by Android 6.0 M and found out that my Android Studio was unable to record the debug process, but somehow other's phone debug report could be recorded. Plus, I tried use Memu emulator and it recorded normally.

Strangely, that device was recognized by Android Studio and ready to be debugged, but no recorded debug report at all from all application that ran on the device. Of course, USB debug was tuned on.

What I did before, I turned off Developer option on that phone in order to play my favourite mobile game (F/GO) which forbids USB Debugging is turned on in the device.

A few hours later, after trying any method in Internet and not success, accidentally I found simple but strange solution that is Restart the phone. I restarted the phone while it was connecting to PC, and somehow the logcat showed all debug process in Logcat like normal.

It sounds like non-engineering solution at all, but that's really work for my case.

Answer 4

In 0.8.2 the DDMS window doesn't show up. However restarting the adb logcat windows by pressing Alt+6 (Twice, if it's already opened) fixes the issue. It worked for me.

Answer 5

Updated: I finally got the cause of the problem in my case. If I switch of my device's wifi, the log shows. Otherwise, the log will not show. I tried several times and it the always show full logs when I turn off my wifi.

My device is: Gsmart Classic, OS: Android OS, v5.1 (Lollipop). I met the problem when I updated the gradle build tool from 'com.android.tools.build:gradle:2.0.0-alpha1' to 'com.android.tools.build:gradle:2.0.0-alpha3' in Android Studio 2.0-preview. After trying all the solutions with no luck, I tried un applied all the instant run choices and re-apply it again. Then the logs show up.

Note: if it still doesn't help. You can as well try to switch back-and-forth the back ground process limit. Unfortunately, I couldn't reproduce the error.