Validation

[manuel-mauky]

No description provided.

[sialcasa]

check
http://stackoverflow.com/questions/23013711/where-should-i-validate-javafx-property-changes
https://www.granitedataservices.com/2012/11/29/thoughts-about-javafx-and-bean-validation/

[sialcasa]

Check this too: https://docs.oracle.com/javase/8/javafx/api/javafx/scene/control/TextFormatter.html

Maybe this is an option for the internal implementation of a validator

Example for a 5-Char Textfield:

TextFormatter<Object> textFormatter = new TextFormatter<>(t -> {
            if (t.getControlNewText().length() > 5) {
                t.setText(""); // negate the change
            }
            return t;
        });

firstnameInput.setTextFormatter(textFormatter);

Example for a Validator implementation with textformatter:

import java.util.function.Predicate;

import javafx.application.Application;
import javafx.beans.property.ReadOnlyBooleanProperty;
import javafx.beans.property.ReadOnlyBooleanWrapper;
import javafx.beans.value.ChangeListener;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.control.TextFormatter;
import javafx.scene.control.TextInputControl;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ValidationApp extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {

        TextField textField = new TextField();
        Button button = new Button("Ok");
        VBox vbox = new VBox(textField, button);

        Validator validator = new Validator(t -> t.length() < 5);
        validator.bindValidation(textField);
        validator.validProperty().addListener((ChangeListener<Boolean>) (observable, oldValue, newValue) -> {
            if (newValue) {
                textField.setStyle("-fx-background-color:-fx-base;");
            } else {
                textField.setStyle("-fx-background-color:red;");
            }
        });

        button.disableProperty().bind(validator.validProperty().not());

        Scene scene = new Scene(vbox);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    class Validator {

        ReadOnlyBooleanWrapper validProperty = new ReadOnlyBooleanWrapper();

        private final Predicate<String> validator;

        public Validator(Predicate<String> validator) {
            this.validator = validator;
        }


        public ReadOnlyBooleanProperty validProperty() {
            return validProperty.getReadOnlyProperty();
        }


        public final void bindValidation(TextInputControl textInput) {
            TextFormatter<String> textFormatter = new TextFormatter<>(t -> {
                String newText = t.getControlNewText();
                validProperty.set(this.validator.test(newText));
                return t;
            });

            textInput.setTextFormatter(textFormatter);
        }
    }

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

}

[sialcasa]

Bean Validation Support

[manuel-mauky]

The implementation of the first version is done. But before we can close this issue we need to add documentation to the wiki.