NPE when trying to create state bitmap

[davidmigloz]

Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'int android.graphics.Bitmap.getWidth()' on a null object reference
       at android.graphics.Bitmap.createBitmap(Bitmap.java:749)
       at com.davidmiguel.multistateswitch.MultiStateSwitch.createStateDrawable(MultiStateSwitch.java:410)
       at com.davidmiguel.multistateswitch.MultiStateSwitch.createStateSelector(MultiStateSwitch.java:366)
       at com.davidmiguel.multistateswitch.MultiStateSwitch.replaceState(MultiStateSwitch.java:4277)
       at android.view.View.performClick(View.java:6897)
       at android.widget.TextView.performClick(TextView.java:12693)
       at android.view.View$PerformClick.run(View.java:26101)
       at android.os.Handler.handleCallback(Handler.java:789)
       at android.os.Handler.dispatchMessage(Handler.java:98)
       at android.os.Looper.loop(Looper.java:164)
       at android.app.ActivityThread.main(ActivityThread.java:6944)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)