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Question

I need to add a bunch of Labels and TextFields on button click. In this case I need to add them as code right, not in the FXML?

I have Automobile class and I have to add like 10 labels and text fields when the user clicks a "Add Automobile" button. Is there a better way than adding them like this:

Label label = new Label("State registration number:");
TextField textField1 = new TextField();
Label label2 = new Label("Brand:");
TextField textField2 = new TextField();
Label label3 = new Label("Model:");
TextField textField3 = new TextField();
Label label4 = new Label("Year of production:");

And so on... And if I need to add to them some other attributes, I need to write like 30+ more lines. Is there a better way of doing this? What is the best practice?

Answer 1

First what you need is an int variable which its value is the amount of labels and textfields you want to create, it would be:

int amount = 10;

You should declare three arrays: One wich contains the text of the labels it would be:

String [] text_labels = new String [] {"State registration number:", "Brand:", "Model:", "..."};

Then you should declare the second array which may be:

Label [] labels = new Label[amount];

And the third one:

TextField [] textfields = new Text field[amount];

Once you haved declared them you have to initialize the labels and textfields. In order to do so you can do:

for(int i = 0; i < amount; i ++) {
  Label label = new Label(text_labels[i]);
  TextField textField = new TextField();
  labels[i] = label;
  textfields[i] = textField;
}

So labels[0] would be the same as the first label you wrote in your code and the same with the textfields.

Answer 2

It's not the greatest solution but a good base to start with

import java.util.Arrays;
import java.util.List;
import java.util.Optional;

import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class MultipleLabelTextFiledApp extends Application {
    private final ObservableList<CustomControl> customControls = FXCollections.observableArrayList();
    private final List<String> labels = Arrays.asList("label1", "label2", "label3", "label4", "label5");

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

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

        labels.stream().forEach(label -> customControls.add(new CustomControl(label)));

        VBox vBox = new VBox();
        vBox.getChildren().setAll(customControls);

        stage.setScene(new Scene(vBox));
        stage.show();

        getCustomControl("label1").ifPresent(customControl -> {
            customControl.getTextField().textProperty().addListener((ChangeListener<String>) (observable, oldValue, newValue) -> {
                System.out.println("textField with label1 handler new text=" + newValue);
            });
        });
    }

    private Optional<CustomControl> getCustomControl(String labelText) {
        return customControls.stream()
        .filter(customControl -> labelText.equals(customControl.getLabel().getText()))
        .findFirst();
    }
}

class CustomControl extends HBox {

    private final Label label = new Label();
    private final TextField textField = new TextField();

    {
        getChildren().addAll(label, textField);
    }

    public CustomControl(String text) {
        label.setText(text);
    }

    public Label getLabel() {
        return label;
    }

    public TextField getTextField() {
        return textField;
    }
}