JavaFX bidirectional binding not working with the control becoming not editable
Bidirectional binding example:
import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class JavaFXApplication10 extends Application {
private Model model = new Model();
@Override
public void start(Stage primaryStage) {
final TextField textField = new TextField();
Bindings.bindBidirectional(textField.textProperty(), model.firstProperty());
// Track the changes
model.firstProperty().addListener(new ChangeListener<String>() {
@Override
public void changed(ObservableValue<? extends String> arg0, String arg1, String arg2) {
System.out.println("model old val: " + arg1);
System.out.println("model new val: " + arg2);
System.out.println();
}
});
textField.textProperty().addListener(new ChangeListener<String>() {
@Override
public void changed(ObservableValue<? extends String> arg0, String arg1, String arg2) {
System.out.println("textField old val: " + arg1);
System.out.println("textField new val: " + arg2);
System.out.println();
}
});
Button btn = new Button();
btn.setText("Change the model's text");
btn.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
model.setFirst("changed from button action");
System.out.println("Done.");
}
});
BorderPane root = new BorderPane();
root.setTop(textField);
root.setBottom(btn);
primaryStage.setScene(new Scene(root, 300, 250));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
// Data Model
public static class Model {
StringProperty first = new SimpleStringProperty();
//getter
public String getFirst() {
return first.get();
}
//setter
public void setFirst(String first) {
this.first.set(first);
}
//new "property" accessor
public StringProperty firstProperty() {
return first;
}
}
}
Bidirectional binding:
1 way - Text entered into textField will be reflected to the model's first stringProperty.
2nd contrary way - By clicking the button, you will notice that when model's first stringProperty is set, the textfield's text value will be also changed.
AgostinoX
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Updated on June 26, 2022Comments
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AgostinoX almost 2 years
Give a very elementary class (imports resolved into javafx packages):
public class T07 extends Application implements Initializable{
with some fields representing controls defined in an .fxml file:
@FXML TextField text01;
and a data model that uses Property wrappers in the most basic way:
public static class DataModel { StringProperty first = new SimpleStringProperty(); //getter public String getFirst() {return first.get();} //setter public void setFirst(String first) {this.first.set(first);} //new "property" accessor public StringProperty firstProperty() {return first;} }
I try to bind the ui control with the data model inside the initialize:
@Override public void initialize(URL arg0, ResourceBundle arg1) { Bindings.bindBidirectional(text01.textProperty(), dm.firstProperty()); }
but doing so, i get a non-editable control. commenting out the Bindings.bindBidirectional line, the control becomes normally editable and its value accessible through text01 field.
What is the missing ingredient in this binding receipe?