Android Question XUI Views views and dialogs- Problem

** Service (starter) Start **
** Activity (main) Create, isFirst = true **
Error occurred on line: 49 (Main)
java.lang.RuntimeException: java.lang.ClassNotFoundException: b4a.example.b4xseekbar
    at anywheresoftware.b4a.keywords.LayoutBuilder.loadLayout(LayoutBuilder.java:170)
    at anywheresoftware.b4a.objects.ActivityWrapper.LoadLayout(ActivityWrapper.java:209)
    at b4a.example.main._activity_create(main.java:413)
    at java.lang.reflect.Method.invoke(Native Method)
    at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:732)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:351)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:255)
    at java.lang.reflect.Method.invoke(Native Method)
    at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:144)
    at b4a.example.main.afterFirstLayout(main.java:104)
    at b4a.example.main.access$000(main.java:17)
    at b4a.example.main$WaitForLayout.run(main.java:82)
    at android.os.Handler.handleCallback(Handler.java:873)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:205)
    at android.app.ActivityThread.main(ActivityThread.java:6991)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:884)
Caused by: java.lang.ClassNotFoundException: b4a.example.b4xseekbar
    at java.lang.Class.classForName(Native Method)
    at java.lang.Class.forName(Class.java:453)
    at java.lang.Class.forName(Class.java:378)
    at anywheresoftware.b4a.keywords.LayoutBuilder.loadLayoutHelper(LayoutBuilder.java:389)
    at anywheresoftware.b4a.keywords.LayoutBuilder.loadLayoutHelper(LayoutBuilder.java:453)
    at anywheresoftware.b4a.keywords.LayoutBuilder.loadLayout(LayoutBuilder.java:148)
    ... 18 more