JavaFX: setting background color for Text controls

Question

I'm using a TextFlow and some Text items to show a styled text, but i cant find a way to set a simple background color for the Text items.

I can set the fill color and font but it does not have a java method or css property that sets its background color.

Answer 1

Based on this solution, this is a quick implementation of a method to provide background coloring for all the Text nodes within a FlowPane, using CSS and the ability to set a series of paint values separated by commas (as much as Text items) and insets for each one of them:

private FlowPane flow;
private Scene scene;

@Override
public void start(Stage primaryStage) {
    Text text0 = new Text("These are several ");
    Text text1 = new Text("Text Nodes ");
    Text text2 = new Text("wrapped in ");
    Text text3 = new Text("a FlowPane");
    text0.setFill(Color.WHEAT);
    text0.setFont(new Font("Times New Roman", 20));
    text1.setFill(Color.WHITE);
    text1.setFont(new Font("Verdana", 32));
    text2.setFill(Color.WHITESMOKE);
    text2.setFont(new Font("Arial", 24));
    text3.setFill(Color.WHITESMOKE);
    text3.setFont(new Font("Arial", 18));

    flow = new FlowPane(text0, text1, text2, text3);
    scene = new Scene(flow, 300, 200);

    primaryStage.setTitle("Hello World!");
    primaryStage.setScene(scene);
    primaryStage.show();

    setBackgroundColors();
    flow.needsLayoutProperty().addListener((obs,d,d1)->setBackgroundColors());        
}

private void setBackgroundColors(){
    final Bounds out = flow.getBoundsInLocal();
    final StringBuilder sbColors = new StringBuilder();
    final StringBuilder sbInsets = new StringBuilder();
    AtomicInteger cont = new AtomicInteger();
    flow.getChildrenUnmodifiable().forEach(n->{
        sbColors.append("hsb(")
                .append((((double)cont.get())/((double)flow.getChildren().size()))*360d)
                .append(", 60%, 90%)");
        Bounds b = ((Text)n).getBoundsInParent();
        sbInsets.append(b.getMinY()).append(" ");
        sbInsets.append(Math.min(scene.getWidth(),out.getMaxX())-b.getMaxX()).append(" ");
        sbInsets.append(Math.min(scene.getHeight(),out.getMaxY())-b.getMaxY()).append(" ");
        sbInsets.append(b.getMinX());
        if(cont.getAndIncrement()<flow.getChildren().size()-1){
            sbColors.append(", ");
            sbInsets.append(", ");
        }
    });
    flow.setStyle("-fx-background-color: "+sbColors.toString()+"; -fx-background-insets: "+sbInsets.toString()+";");
}

This will lead to this:

and after resizing the scene:

EDIT

Based on the OP request of using a TextFlow layout instead of a FlowPane, since Text nodes can be spanned over several lines within a TextFlow, the given solution will no longer be valid, as the bounding box of each text node will overlap others.

As a workaround, we can split the Text nodes in single word Text nodes, while keeping the same background color for those in the same original phrase.

I won't go into the splitting logic, but I will add a list of indices, where each index maps the text node with its index of background color.

private FlowPane flow;
private Scene scene;

private final List<Integer> indices=Arrays.asList(0,0,0,1,1,2,2,3,3);

@Override
public void start(Stage primaryStage) {
    List<Text> text0 = Arrays.asList(new Text("These "), new Text("are "), new Text("several "));
    List<Text> text1 = Arrays.asList(new Text("Text "), new Text("Nodes "));
    List<Text> text2 = Arrays.asList(new Text("wrapped "), new Text("in "));
    List<Text> text3 = Arrays.asList(new Text("a "), new Text("FlowPane"));
    text0.forEach(t->t.setFill(Color.WHEAT));
    text0.forEach(t->t.setFont(new Font("Times New Roman", 20)));
    text1.forEach(t->t.setFill(Color.WHITE));
    text1.forEach(t->t.setFont(new Font("Verdana", 32)));
    text2.forEach(t->t.setFill(Color.WHITESMOKE));
    text2.forEach(t->t.setFont(new Font("Arial", 24)));
    text3.forEach(t->t.setFill(Color.WHITESMOKE));
    text3.forEach(t->t.setFont(new Font("Arial", 18)));

    flow = new FlowPane();
    flow.getChildren().addAll(text0);
    flow.getChildren().addAll(text1);
    flow.getChildren().addAll(text2);
    flow.getChildren().addAll(text3);
    scene = new Scene(flow, 300, 200);

    primaryStage.setTitle("Hello World!");
    primaryStage.setScene(scene);
    primaryStage.show();

    setBackgroundColors();
    flow.needsLayoutProperty().addListener((obs,d,d1)->setBackgroundColors());        
}

private void setBackgroundColors(){
    final Bounds out = flow.getBoundsInLocal();
    final StringBuilder sbColors = new StringBuilder();
    final StringBuilder sbInsets = new StringBuilder();
    AtomicInteger cont = new AtomicInteger();
    flow.getChildrenUnmodifiable().forEach(n->{
        sbColors.append("hsb(")
                .append((double)indices.get(cont.get())/(double)(indices.get(flow.getChildren().size()-1)+1)*360d)
                .append(", 60%, 90%)");
        Bounds b = ((Text)n).getBoundsInParent();
        sbInsets.append(b.getMinY()).append(" ");
        sbInsets.append(Math.min(scene.getWidth(),out.getMaxX())-b.getMaxX()-1).append(" ");
        sbInsets.append(Math.min(scene.getHeight(),out.getMaxY())-b.getMaxY()).append(" ");
        sbInsets.append(b.getMinX());
        if(cont.getAndIncrement()<flow.getChildren().size()-1){
            sbColors.append(", ");
            sbInsets.append(", ");
        }
    });
    flow.setStyle("-fx-background-color: "+sbColors.toString()+"; -fx-background-insets: "+sbInsets.toString()+";");
}

This FlowPane now behaves as a TextFlow: