To reproduce, run the example below, press F1 to toggle the width of the axis and note the print out of the displayPosition before/after the resize

expected:
"after" different from before,
"after" should be half of the current width of the axis

actual:
after same as before

Looks like the internal fields (specifically offset and scale) are only updated on the _next_ layout pulse. Should be done immediately - the conversion methods must return the correct conversion at _any_ time.

As long as axis doesn't comply to its contract, other controls (like f.i. Slider which was my driving force to use the axis in a cleaner sliderSkin, see http://stackoverflow.com/q/34139076/203657) can't fully rely on its services, at least not during a layout round. That's why I (try to :-) uppen the priority to p3.

The code example:

public class AxisConversionBug extends Application {

    private Parent getContent() {
        NumberAxis axis = new NumberAxis(0, 100, 25);
        Region region = new Region() {
            {
                getChildren().add(axis);
            }
        };
        BorderPane pane = new BorderPane(region);
        axis.setManaged(false);
        double initial = 100;
        axis.resize(initial, axis.getPrefHeight());
        axis.addEventFilter(KeyEvent.KEY_PRESSED, e -> {
            if (e.getCode() == KeyCode.F1) {
                
                double positionBefore = axis.getDisplayPosition(50);
                double axisWidth = axis.getWidth() < region.getWidth()
                        ? region.getWidth() : initial;
                axis.resize(axisWidth, axis.getHeight());
                // following doen't make a difference
                // axis.requestAxisLayout();
                region.requestLayout();
                double positionAfter = axis.getDisplayPosition(50);
                LOG.info("position before/after resize: " + positionBefore +
                        " / " + positionAfter + " width: " + axis.getWidth()) ;
            }
        });
        axis.setFocusTraversable(true);
        axis.requestFocus();
        return pane;
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        primaryStage.setScene(new Scene(getContent(), 500, 200));
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
 
    @SuppressWarnings("unused")
    private static final Logger LOG = Logger.getLogger(AxisInvalidate.class
            .getName());

}