android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
49
What is a NullPointerException, and how do I fix it?
70532
NullReferenceException after POST
77648
How to get the result of OnPostExecute() to main activity because AsyncTask is a separate class?
81565
getClass().getResource() always returning null
44087
ArrayAdapter requires ID to be a TextView error
70648
ActionListener isn't Implementing
69180
onActivityResult() called prematurely
113741
Using onClick attribute in layout xml causes a NoSuchMethodException in Android dialogs
74172
Binary XML file line #2: Error inflating class android.widget.LinearLayout
137692
NullPointerException when working with arrays
10581
Avoiding NullPointerException in Java
73034
StringBuilder append() and null values
96311
NullPointerException when installing the Android SDK on Mac OS X
24517
MVC Spring Implementation - error: java.lang.NullPointerException
32065
Attempt to de-reference a null object: Trigger
80018
Accessing class members on a NULL pointer
19797
when EditText is empty and click calculateButton, app crashes