Center text on Canvas?

Question

Can someone please give me an example on how to center text on a JavaFX 2 Canvas?

GraphicsContext has some functions like setTextAlign, but I am not sure on how to use all those methods and which of them I really need. I want to center my text vertically and horizontally.

Answer 1

1. Set the text align to center.
2. Set the text baseline to center.
3. Draw the text in the center of your canvas (by positioning it at half the canvas width and height).

Here is a sample:

import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.geometry.VPos;
import javafx.scene.*;
import javafx.scene.canvas.*;
import javafx.scene.layout.StackPane;
import javafx.scene.text.TextAlignment;
import javafx.stage.Stage;

public class TextCanvas extends Application {
    @Override public void start(Stage primaryStage) {
        Canvas canvas = new Canvas(175, 40);
        GraphicsContext gc = canvas.getGraphicsContext2D();
        gc.setTextAlign(TextAlignment.CENTER);
        gc.setTextBaseline(VPos.CENTER);
        gc.fillText(
            "Text centered on your Canvas", 
            Math.round(canvas.getWidth()  / 2), 
            Math.round(canvas.getHeight() / 2)
        );

        StackPane layout = new StackPane();
        layout.getChildren().addAll(canvas);

        primaryStage.setScene(new Scene(layout));
        primaryStage.show();
    }
    public static void main(String[] args) { launch(args); }
}