nullpointerexception - Locating Errors When Developing Android Apps -

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i'm working on first android app , honest i'm not sure of i'm doing. right i'm stuck on nullpointerexception created line refers class that, in turn, refers class.

how can locate error?

the word looking debug. if using eclipse, it's easy debug program in cases. 2 main options in eclipse use logger debug prints logcat, or debug program step step detect relevant errors. here tutorial both options , here nice video tutorial in youtube regarding debug in eclipse.


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