package de.hems.trafficsim; import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.TextView; import java.util.Observable; import java.util.Observer; public class MainActivity extends AppCompatActivity implements Observer { protected Track track; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); this.track = new Track(); this.track.addObserver(this); } @Override public void update(Observable observable, Object o) { String s = ""; for (Vehicle v: this.track.getVehicles()){ s+="Pos = " + v.getPosition() +"\n"; } TextView view = (TextView) findViewById(R.id.debugTextView); view.setText(s); view.invalidate(); } public void onStepButtonClick (View view){ this.track.timeElapse(50); } }