Why cant get device id in non-Main Class?

Question

I retrieve the device ID in my main activity by doing:

String UDID = System.getString(this.getContentResolver(), System.ANDROID_ID);

Later in my code I start a new Activity in which I need the UDID as well, but when I run the same line of code it crashes:

01-01 12:20:54.793: ERROR/AndroidRuntime(868): FATAL EXCEPTION: main
01-01 12:20:54.793: ERROR/AndroidRuntime(868): java.lang.NullPointerException
01-01 12:20:54.793: ERROR/AndroidRuntime(868):     at android.content.ContextWrapper.getContentResolver(ContextWrapper.java:91)

I understand that it has to do something with the context, but cant figure out how to fix this. Of course I could do putExtra, but I guess there must be a better way.

Please check this: http://stackoverflow.com/questions/2785485/is-there-a-unique-android-device-id — strongmayer, Jan 01 '12 at 11:26

Rajdeep Dua · Accepted Answer · 2012-01-01T12:21:14.450

0

Seems to work for me though this is deprecated

 String id_deprecated = System.getString(this.getContentResolver(),      
                                         android.provider.Settings.System.ANDROID_ID);

You should use the ANDROID_ID defined in Settings.Secure

 String id_new =System.getString(this.getContentResolver(), 
                                    android.provider.Settings.Secure.ANDROID_ID);

edited Jan 01 '12 at 12:21

answered Jan 01 '12 at 12:14

Rajdeep Dua

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Still crashes, even with id_new. 01-01 13:54:30.536: ERROR/AndroidRuntime(477): at android.content.ContextWrapper.getContentResolver(ContextWrapper.java:91) – michaelsmith Jan 01 '12 at 12:55
Are you sure 'this' is an instance of an activity? – Rajdeep Dua Jan 01 '12 at 13:03

Why cant get device id in non-Main Class?

1 Answers1