javafx - Java FX TextField blur

Question

Can anyone tell me why sometimes JavaFX displays the content of a TextField with a blur effect on it? It seems to be random and occurs in any of my TextFields. Please see the image attached.

Answer 1

Focusing on the intermittent rendering artifact mentioned here, the 2 glyph looks like it's been rendered twice, with one copy shifted horizontally relative to the other. Such apparently random anomalies are notoriously difficult to identify. Myriad causes may include incorrect synchronization, improper layout, defects in the host platform's rendering pipeline, etc. For reference, the example below may allow you to test on disparate platforms.

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

/**
 * @see https://stackoverflow.com/a/53989899/230513
 */
public class TextFieldTest extends Application {

    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("TextFieldTest");
        BorderPane root = new BorderPane();
        root.setCenter(createContent());
        root.setBottom(createVersion());
        Scene scene = new Scene(root);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    private Node createContent() {
        HBox row1 = new HBox(4);
        Label channelsLabel = new Label("Channels:");
        TextField channelsText = new TextField("2");
        channelsText.setPrefWidth(32);
        Label separatorLabel = new Label("Separator:");
        TextField separatorText = new TextField("!");
        separatorText.setPrefWidth(32);
        row1.setPadding(new Insets(8));
        row1.getChildren().addAll(
            channelsLabel, channelsText, separatorLabel, separatorText);
        HBox row2 = new HBox(4, new Label("Label:"), new TextField());
        row2.setPadding(new Insets(8));
        return new VBox(row1, row2);
    }

    private Label createVersion() {
        Label label = new Label(
            System.getProperty("os.name") + " v"
            + System.getProperty("os.version") + "; Java v"
            + System.getProperty("java.version"));
        label.setPadding(new Insets(8));
        return label;
    }

    public static void main(String[] args) {
        launch(args);
    }
}

As shown in the Modena example, an intentional blur effect indicates that the text field is focused:

The detail that gives rise to the blurred effect in your image is a compound border, seen below at 2x:

Comparable effects are seen here for buttons (top row) and default buttons (bottom row):