액티비티 레이아웃 드로블을 바꾸고 싶어서요..

Question

LinearLayout a = (LinearLayout)findViewById(R.id.mainlinear);
            
                a.setBackground( (Drawable)getResources().getDrawable(R.drawable.coin_background2));
이렇게 해보았는데 이런 에러가뜨네요 ㅠ


06-22 11:59:04.258: W/dalvikvm(7914): threadid=1: thread exiting with uncaught exception (group=0x419e0ba8)
06-22 11:59:04.266: E/AndroidRuntime(7914): FATAL EXCEPTION: main
06-22 11:59:04.266: E/AndroidRuntime(7914): Process: com.exam, PID: 7914
06-22 11:59:04.266: E/AndroidRuntime(7914): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=0, result=-1, data=Intent {  }} to activity {com.exam/com.exam.coinBlockIntroActivity}: java.lang.NullPointerException
06-22 11:59:04.266: E/AndroidRuntime(7914):     at android.app.ActivityThread.deliverResults(ActivityThread.java:3368)
06-22 11:59:04.266: E/AndroidRuntime(7914):     at android.app.ActivityThread.handleSendResult(ActivityThread.java:3411)
06-22 11:59:04.266: E/AndroidRuntime(7914):     at android.app.ActivityThread.access$1300(ActivityThread.java:138)
06-22 11:59:04.266: E/AndroidRuntim

 

 

ㅠㅠ뭐가 문제일까요?

Answer 1

a.setBackgroundResource(R.drawable.coin_background2);