How can I figure out what in my code is causing the entire android OS to freeze?

Question

I don't know how to debug this because it's not a typical crash, and I can't get a stack trace. Sometimes, the OS just restarts itself. Other times, I have to take out the battery,

It happens, some of the time, when the user clicks on the button to take a picture. This button calls takePicture() which simply makes an intent, puts the data (JPEG) into an extra, and then calls startActivity(intent);

I don't have any extra thread stuff happening. Could a need of those be causing the OS to lock up? Or could it be a lack of memory? I don't know how to begin troubleshooting this.

Thanks

Edit: Also, when the freeze occurs, if I plug my phone back in there are dozens of instances of my app running for some reason.

Is this a problem with your app triggering these freezes, or with your device in general? If the latter, the [Android Enthusiast](http://android.stackexchange.com/) Stack Exchange site is more appropriate than Stack Overflow. — thegrinner, May 27 '14 at 14:02
try it in different devices if it behaves the same then (freezes) then you know for sure that there is something wrong in your code I have some android mobile that crashes even for simple apps due to lack of ram — Illegal Argument, May 27 '14 at 14:36

score 0 · Accepted Answer · answered May 27 '14 at 14:00

0

You can use LogCat in Eclipse and write logs after every line of code. This will probably help you:

http://developer.android.com/tools/debugging/debugging-log.html

You can log using the following command:

Log.i("MyActivity", "A relevant comment");

It is also useful to put a filter in LogCat with "MyActivity" as the Log Tag.

answered May 27 '14 at 14:00

Cydrick Trudel

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Is there a way to save that those log messages to my phone? I can't seem to replicate it when it's plugged in to my computer. – user2581666 May 27 '14 at 14:10
Use this: http://stackoverflow.com/questions/3359692/how-to-redirect-my-log-output-from-logcat-to-the-sd-card-on-an-android-device – Cydrick Trudel May 27 '14 at 14:16
Thank you, that looks promising! – user2581666 May 27 '14 at 14:20
If you think the solution answers your question, please mark it as accepted by clicking the checkmark next to this answer. Have a nice day! – Cydrick Trudel May 27 '14 at 14:22

score 0 · Answer 2 · answered May 27 '14 at 14:00

You can simply debug it and find out which line is causing it. Usually when phone get freezes it is because a wrong use in a native component - like Camera, MediaPlayer, etc..

try to comment the initialization / reset method to check if your app still freezes.

How can I figure out what in my code is causing the entire android OS to freeze?

2 Answers2