设置numberPiscker时出错。

报错日志：java.lang.IndexOutOfBoundsException: setSpan (2 ... 2) ends beyond length 0
at android.text.SpannableStringBuilder.checkRange(SpannableStringBuilder.java:1016)
at android.text.SpannableStringBuilder.setSpan(SpannableStringBuilder.java:592)
at android.text.SpannableStringBuilder.setSpan(SpannableStringBuilder.java:588)
at android.text.Selection.setSelection(Selection.java:76)
at android.widget.EditText.setSelection(EditText.java:87)
at android.widget.NumberPicker$SetSelectionCommand.run(NumberPicker.java:2123)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:611)
at dalvik.system.NativeStart.main(Native Method)
大神们，帮忙看看，不盛感激。