title: Cannot determine width of button because getWidth() returns 0 in JavaFx
body: <p>I am working on an application where I have to display a tree. I started from: <a href="https://stackoverflow.com/questions/30679025/graph-visualisation-like-yfiles-in-javafx">Graph Visualisation (like yFiles) in JavaFX</a> . The tree gets displayed, but for ButtonCell calling the method getWidth or any variant of getBoundsInLocal, getBoundsInParent, getLayoutBounds returns 0 and getPrefWidth returns -1.</p>
  
  <p>How do I get the width and height of the button?</p>