How to debug in Android Studio Logcat

Question

I am new to Android Studio and Android programming and am attempting to follow a how to lesson. I am having a lot of trouble following Android Studio Logcat because it is not as straightforward to me as any IDEs have used. Could someone please decode what things mean in my errors? I need to learn how to use Logcat since the explanations I see online are too simplified and do not cover much.

What exactly is:"2359-13990/"?
How do I find the place in the code that caused the errors?
What exactly does my error output from Logcat mean?

Due to the space limit, I have changed my post and now have only errors instead of verbose. Here are my errors in Logcat:

06-21 21:11:46.347 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3105, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:11:46.348 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:11:46.348 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:11:46.349 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:11:47.142 29992-29992/? E/cutils-trace: Error opening trace file: Permission denied (13)
06-21 21:11:47.185 29992-29992/? E/memtrack: Couldn't load memtrack module (No such file or directory)
06-21 21:11:47.185 29992-29992/? E/android.os.Debug: failed to load memtrack module: -2
06-21 21:11:47.398 30006-30006/? E/cutils-trace: Error opening trace file: Permission denied (13)
06-21 21:11:47.440 30006-30006/? E/memtrack: Couldn't load memtrack module (No such file or directory)
06-21 21:11:47.440 30006-30006/? E/android.os.Debug: failed to load memtrack module: -2
06-21 21:11:47.770 30029-30029/? E/cutils-trace: Error opening trace file: Permission denied (13)
06-21 21:11:47.811 30029-30029/? E/memtrack: Couldn't load memtrack module (No such file or directory)
06-21 21:11:47.812 30029-30029/? E/android.os.Debug: failed to load memtrack module: -2
06-21 21:11:49.172 30041-30041/? E/cutils-trace: Error opening trace file: Permission denied (13)
06-21 21:11:49.227 30046-30046/? E/cutils-trace: Error opening trace file: Permission denied (13)
06-21 21:11:49.229 30041-30041/? E/memtrack: Couldn't load memtrack module (No such file or directory)
06-21 21:11:49.229 30041-30041/? E/android.os.Debug: failed to load memtrack module: -2
06-21 21:11:49.279 30046-30046/? E/memtrack: Couldn't load memtrack module (No such file or directory)
06-21 21:11:49.279 30046-30046/? E/android.os.Debug: failed to load memtrack module: -2
06-21 21:11:49.331 30063-30070/? E/art: Failed sending reply to debugger: Broken pipe
06-21 21:11:52.997 30063-30063/com.example.android.sunshine E/AndroidRuntime: FATAL EXCEPTION: main
                                                                              Process: com.example.android.sunshine, PID: 30063
                                                                              java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.sunshine/com.example.android.sunshine.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ProgressBar.setVisibility(int)' on a null object reference
                                                                                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
                                                                                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
                                                                                  at android.app.ActivityThread.-wrap12(ActivityThread.java)
                                                                                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
                                                                                  at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                                  at android.os.Looper.loop(Looper.java:154)
                                                                                  at android.app.ActivityThread.main(ActivityThread.java:6119)
                                                                                  at java.lang.reflect.Method.invoke(Native Method)
                                                                                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                                                                                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
                                                                               Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ProgressBar.setVisibility(int)' on a null object reference
                                                                                  at com.example.android.sunshine.MainActivity$FetchWeatherTask.onPreExecute(MainActivity.java:97)
                                                                                  at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:620)
                                                                                  at android.os.AsyncTask.execute(AsyncTask.java:567)
                                                                                  at com.example.android.sunshine.MainActivity.loadWeatherData(MainActivity.java:74)
                                                                                  at com.example.android.sunshine.MainActivity.onCreate(MainActivity.java:63)
                                                                                  at android.app.Activity.performCreate(Activity.java:6679)
                                                                                  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
                                                                                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
                                                                                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
                                                                                  at android.app.ActivityThread.-wrap12(ActivityThread.java) 
                                                                                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
                                                                                  at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                                  at android.os.Looper.loop(Looper.java:154) 
                                                                                  at android.app.ActivityThread.main(ActivityThread.java:6119) 
                                                                                  at java.lang.reflect.Method.invoke(Native Method) 
                                                                                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                                                                                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 
06-21 21:11:53.668 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3113, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:11:53.669 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:11:53.669 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:11:53.669 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:11:58.689 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3121, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:11:58.689 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:11:58.689 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:11:58.690 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:12:03.709 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3129, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:12:03.711 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:12:03.712 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:12:03.712 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:12:08.742 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3137, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:12:08.742 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:12:08.742 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:12:08.742 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:12:13.764 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3145, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:12:13.764 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:12:13.765 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:12:13.765 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:12:18.790 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3153, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:12:18.790 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:12:18.790 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:12:18.791 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
06-21 21:12:23.808 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord: Could not get audio input for session 3161, record source 1999, sample rate 16000, format 0x1, channel mask 0x10, flags 0
06-21 21:12:23.808 2359-13990/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -22.
06-21 21:12:23.808 2359-13990/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
06-21 21:12:23.808 2359-13990/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded

These don't look like your app's error. Select your app in the "Android Monitor". You can select it in second dropdown present there. Then attach those logs. — priyanka p, Jun 22 '17 at 04:35
I am new to posting but not reading this site. How do I attach a log on this site? — J. Doe, Jun 22 '17 at 04:44

priyanka p · Answer 1 · 2017-06-22T05:21:21.790

You look for your package name (if you have not selected your project in the dropdown for logging). In you case I suppose its "com.example.android.sunshine".

Just after your package name you will find the exception and more details.

ComponentInfo{com.example.android.sunshine/com.example.android.sunshine.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void'

Below that you can find stacktrace. In that stacktrace again find your package name and you will find exact line where error occurred.

com.example.android.sunshine.MainActivity$FetchWeatherTask.onPreExecute(MainActivity.java:97)

How to debug in Android Studio Logcat

1 Answers1