How to find error from LogCat in android?

Question

Method or Hint for finding error from LogCat. How to find and solve error from Logcat?

Error will be shown in red color. In eclipse click on DDMS perspective. In DDMS perspective, left panel, select emulator (or the device listed). And you will get the logcat. — kumar, Dec 13 '12 at 10:15
What do you mean by "find"? The error usually gets printed in LogCat as it does in a normal java program — HashtagMarkus, Dec 13 '12 at 10:15

score 5 · Answer 1 · answered Dec 13 '12 at 10:20

I try to explain on a very basic example of logcat output taken from different post :

12-13 12:41:57.052: W/System.err(542): org.json.JSONException: No value for TAG_CONTACTS
12-13 12:41:57.052: W/System.err(542):  at org.json.JSONObject.get(JSONObject.java:354)
12-13 12:41:57.052: W/System.err(542):  at org.json.JSONObject.getJSONArray(JSONObject.java:544)
12-13 12:41:57.052: W/System.err(542):  at com.androidhive.jsonparsing.AndroidJSONParsingActivity.onCreate(AndroidJSONParsingActivity.java:56)
12-13 12:41:57.063: W/System.err(542):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-13 12:41:57.063: W/System.err(542):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
12-13 12:41:57.063: W/System.err(542):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
12-13 12:41:57.063: W/System.err(542):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)
12-13 12:41:57.063: W/System.err(542):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
12-13 12:41:57.063: W/System.err(542):  at android.os.Handler.dispatchMessage(Handler.java:99)
12-13 12:41:57.072: W/System.err(542):  at android.os.Looper.loop(Looper.java:123)
12-13 12:41:57.072: W/System.err(542):  at android.app.ActivityThread.main(ActivityThread.java:3683)
12-13 12:41:57.072: W/System.err(542):  at java.lang.reflect.Method.invokeNative(Native Method)
12-13 12:41:57.072: W/System.err(542):  at java.lang.reflect.Method.invoke(Method.java:507)
12-13 12:41:57.072: W/System.err(542):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)

As you can see from first line exception is "JSONException" which heppened because of "No value for TAG_CONTACTS". From line number 4 you can see, that it happened in "AndroidJSONParsingActivity" on line 56. Now when you know what is the exception and where it happens, you should be able to solve it !

score 3 · Answer 2 · answered Jan 23 '14 at 21:47

3

In LogCat you will find among all those run time errors there is a tag "Caused by" under text attribute.you will click the next line of that error and that will point you to the code where that error is occurring.

answered Jan 23 '14 at 21:47

Sifat Ifty

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score 1 · Answer 3 · edited Jan 15 '21 at 13:33

1

In Android Studio You will See Logcat in Bottom switch to error in that and you have to read all red messages . these are errors

edited Jan 15 '21 at 13:33

Sam Massy

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answered Dec 13 '12 at 10:15

Abhi

8,935
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score 1 · Accepted Answer · answered Sep 06 '16 at 13:01

1

I like this approach:

adb logcat -s System.err

answered Sep 06 '16 at 13:01

DenisKolodin

13,501
3
62
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How to find error from LogCat in android?

4 Answers4

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