How to update the WindowManager view?

I try to create an animation with windowmanager in a service but when executing it throws me the exception:

FATAL EXCEPTION: main                                                                                Process: com. {Name}, PID: 24454                                                                                java.lang.IllegalStateException: onMeasure () did not set the measured dimension by calling setMeasuredDimension ()                                                                                    at android.view.View.measure (View.java:18000)                                                                                    at android.view.ViewRootImpl.performMeasure (ViewRootImpl.java:2438)                                                                                    at android.view.ViewRootImpl.measureHierarchy (ViewRootImpl.java:1418)                                                                                    at android.view.ViewRootImpl.performTraversals (ViewRootImpl.java:1642)                                                                                    at android.view.ViewRootImpl.doTraversal (ViewRootImpl.java:1296)                                                                                    at android.view.ViewRootImpl $ TraversalRunnable.run (ViewRootImpl.java:6742)                                                                                    at android.view.Choreographer $ CallbackRecord.run (Choreographer.java:826)                                                                                    at android.view.Choreographer.doCallbacks (Choreographer.java:629)                                                                                    at android.view.Choreographer.doFrame (Choreographer.java:597)                                                                                    at android.view.Choreographer $ FrameDisplayEventReceiver.run (Choreographer.java:812)                                                                                    at android.os.Handler.handleCallback (Handler.java:815)                                                                                    at android.os.Handler.dispatchMessage (Handler.java:104)                                                                                    at android.os.Looper.loop (Looper.java:194)                                                                                    at android.app.ActivityThread.main (ActivityThread.java:5931)                                                                                    at java.lang.reflect.Method.invoke (Native Method)                                                                                    at java.lang.reflect.Method.invoke (Method.java:372)                                                                                    at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run (ZygoteInit.java:987)                                                                                    at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:782)

Here is the code

public class Servicio extends Service {
private LinearLayout ll;
private WindowManager.LayoutParams parameters;
private WindowManager.LayoutParams updateparameters;
private WindowManager wm;
private Bitmap bm;
private int ancho;
private int alto;
public void onCreate(){
    super.onCreate();
    Toast.makeText(Servicio.this, "onCreate", Toast.LENGTH_SHORT).show();

    WindowManager wm1 = (WindowManager)getSystemService(Context.WINDOW_SERVICE);
    Display display = wm1.getDefaultDisplay();
    Point size = new Point();
    display.getSize(size);

    alto=size.x/4;
    ancho=(size.x/4)*7/5;

    try{
        bm = BitmapFactory.decodeResource(getResources(), R.drawable.imagen);
    }catch(Exception e){}

    ll=new LinearLayout(this);
    LinearLayout.LayoutParams llParameters=new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,LinearLayout.LayoutParams.MATCH_PARENT);
    ll.setBackground(new BitmapDrawable(this.getResources(), bm));
    ll.setLayoutParams(llParameters);
    parameters=new WindowManager.LayoutParams(alto,ancho,0,0, WindowManager.LayoutParams.TYPE_PHONE,WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE, PixelFormat.TRANSLUCENT);
    updateparameters=new WindowManager.LayoutParams(alto,ancho,0,0, WindowManager.LayoutParams.TYPE_PHONE,WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE, PixelFormat.TRANSLUCENT);
    parameters.x=-size.x/2;
    parameters.y=0;
    wm=(WindowManager)getSystemService(WINDOW_SERVICE);
    wm.addView(ll,parameters);
    new Thread(new Runnable() {
        public void run() {
            Looper.prepare();
            while(true){
                updateparameters.x=a;
                updateparameters.y=0;
                a++;
                update();/*Este metodo me lanza FatalExcepción. Si lo colocase fuera de este nuevo hilo, la excepción no sucede*/
            }
        }
    }).start();
}
public int onStartCommand(Intent intent, int flags, int startId){
    return START_STICKY ;
}
public void onDestroy(){
    super.onDestroy();
    Toast.makeText(Servicio.this, "onDestroy", Toast.LENGTH_SHORT).show();
    wm.removeView(ll);
}
public IBinder onBind(Intent intent) {
    return null;
}
public void update(){
    wm.updateViewLayout(ll,updateparameters);
}

}