Develop Reference

JavaFX - Bind LocalTime to TableColumn via Property

I am using JavaFX to wrap existing classes with properties, so that I may bind them to a GUI directly without having to manually hook up events. Here is a sample of my code:
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.property.ObjectProperty;
import controller.NewOrder;
import controller.Types.Action;
public class ObservableOrder extends NewOrder
{
private StringProperty m_account;
private ObjectProperty<Action> m_action;
public ObservableOrder()
{
// CONSTRUCT PROPERTIES
m_account = new SimpleStringProperty(this, "m_account");
m_action = new SimpleObjectProperty<Action>(this, "m_action", Action.BUY);
}
// GETTERS
#Override public String account() { return m_account.get(); }
#Override public Action action() { return m_action.get(); }
// SETTERS
#Override public void account(String v) { accountProperty().set(v); }
#Override public void action(Action v) { actionProperty().set(v); }
// PROPERTY GETTERS
public StringProperty accountProperty() { return m_account; }
public ObjectProperty<Action> actionProperty() { return m_action; }
}
This works for integers, strings and enums. What I would like to do next is wrap a LocalTime object with properties and bind it to a table column, but I can't figure it out. Should I use ObservableValue instead? Any help is appreciated. Thx

TextFormatter throws exception when binding (bidirectional) to a null string

Edit
Apparently this is a bug. The report I've made can be found here. As #James_D noted, this is not an issue with the binding, but it is enough to set the text to null after it has been set to a non-null value.
I am having troubles with JavaFX TextFormatter. I want to limit the length of text in a text field to 10 characters, but I find the if the text property was bound to a non-null value, and then is unbound and rebound to a null value, the text formatter throws an exception:
java.lang.IllegalArgumentException: The start must be <= the end
upon calling TextFormatter.Change#getControlNewText, which is weird, because if anything I would have expected a null reference exception.
I attach a simple code for a complete example exhibiting this problem. If there is anything I'm doing wrong please let me know
package sample;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;
public class Main extends Application {
private Model m;
private int num = 0;
#Override
public void start(Stage primaryStage) throws Exception {
TextField tf = new TextField();
tf.setTextFormatter(new TextFormatter<>(change -> change.getControlNewText().length() > 10 ? null : change));
Button b = new Button("Click!");
b.setOnAction(ev -> {
if (m != null) {
tf.textProperty().unbindBidirectional(m.nameProperty());
}
m = new Model();
if (num % 2 == 0) {
System.out.println("Setting foo");
m.setName("foo");
}
num++;
tf.textProperty().bindBidirectional(m.nameProperty());
}
);
VBox vb = new VBox(tf, b);
primaryStage.setScene(new Scene(vb));
primaryStage.show();
}
public class Model {
private SimpleStringProperty name = new SimpleStringProperty(this, "name");
public StringProperty nameProperty() {
return name;
}
public String getName() {
return name.get();
}
public void setName(String name) {
this.name.set(name);
}
}
public static void main(String[] args) {
launch(args);
}
}
In this code there is a TextField with a TextFormatter rejecting all changed which result in a string of length>10. When the button is clicked a new Model object is created, and it's name property is bound to the TextField's text property - not before the old Model is unbound. The model is alternating between being initialized with "foo" as name, or not being initialized with a name - that is - the name remains null.
Upon first clicking the button you should see the text being changed to "foo", and when next clicking the button the exception is thrown.

This looks like a bug (it seems like the text formatter's filter doesn't properly handle the text being set to null). A possible workaround is to bind the value property of the text formatter, instead of the text property of the text field:
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;
public class Main extends Application {
private Model m;
private int num = 0;
#Override
public void start(Stage primaryStage) throws Exception {
TextField tf = new TextField();
TextFormatter<String> textFormatter = new TextFormatter<>(
TextFormatter.IDENTITY_STRING_CONVERTER, "", change ->
change.getControlNewText().length() > 10 ? null : change);
tf.setTextFormatter(textFormatter);
Button b = new Button("Click!");
b.setOnAction(ev -> {
if (m != null) {
// tf.textProperty().unbindBidirectional(m.nameProperty());
textFormatter.valueProperty().unbindBidirectional(m.nameProperty());
}
m = new Model();
if (num % 2 == 0) {
System.out.println("Setting foo");
m.setName("foo");
}
num++;
// tf.textProperty().bindBidirectional(m.nameProperty());
textFormatter.valueProperty().bindBidirectional(m.nameProperty());
}
);
VBox vb = new VBox(tf, b);
primaryStage.setScene(new Scene(vb));
primaryStage.show();
}
public class Model {
private SimpleStringProperty name = new SimpleStringProperty(this, "name", "");
public StringProperty nameProperty() {
return name;
}
public String getName() {
return name.get();
}
public void setName(String name) {
this.name.set(name);
}
}
public static void main(String[] args) {
launch(args);
}
}

Bind ComboBox#itemsProperty to Map#keySet

For what I am doing, I need to set the members of a javafx.scene.control.ComboBox to the members of a Map#keySet() Set.
The options available in the ComboBox need to update as the keys of the Map are updated. (Basically, I want to use the ComboBox to select members from the Map, which WILL be updated at runtime.)
Unfortunately, neither ComboBox#itemsProperty().bind(ObservableValue<>) nor ComboBox#itemsProperty().set(ObservableList<>) will take a Set<>, so the direct route of connecting the itemsProperty to the Map#keySet doesn't work.
Basically:
How can I make it so the ComboBox's items are the members of a Map's keySet?
Again, the behavior that I need is that the ComboBox's items will reflect the KeySet of my Map. (The Map can be any implementation of Map.)
EDIT: The problem seems to be creating an ObservableList out of a Collection -- in this case a Set -- without making it just a copy, but rather a reference to the Set, in order that the ObservableList will reflect the Set's contents.

If you have an ObservableMap, you can add a listener to it. For example:
ComboBox<String> comboBox = ... ;
ObservableMap<String, Something> map = ... ;
map.addListener((MapChangeListener.Change<? extends String, ? extends Something> c) ->
comboBox.getItems().setAll(map.keySet()));
You can also do this with a binding, though I don't think it's any cleaner:
comboBox.itemsProperty().bind(Bindings.createObjectBinding(() ->
FXCollections.observableArrayList(map.keySet()),
map);
Here's a SSCCE, demonstrating both techniques:
import java.util.concurrent.atomic.AtomicInteger;
import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.collections.FXCollections;
import javafx.collections.MapChangeListener;
import javafx.collections.ObservableMap;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.scene.control.TextField;
import javafx.scene.control.Tooltip;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class BindItemsToKeySet extends Application {
#Override
public void start(Stage primaryStage) {
ObservableMap<Integer, Item> itemLookupById = FXCollections.observableHashMap();
ComboBox<Integer> listenerCombo = new ComboBox<>();
ComboBox<Integer> bindingCombo = new ComboBox<>();
itemLookupById.addListener((MapChangeListener.Change<? extends Integer, ? extends Item> c) ->
listenerCombo.getItems().setAll(itemLookupById.keySet())
);
bindingCombo.itemsProperty().bind(Bindings.createObjectBinding(() ->
FXCollections.observableArrayList(itemLookupById.keySet()),
itemLookupById));
TextField textField = new TextField();
textField.setOnAction(e -> {
if (textField.getText().isEmpty()) {
return ;
}
Item item = new Item(textField.getText());
itemLookupById.put(item.getId(), item);
textField.clear();
});
textField.setTooltip(new Tooltip("Type an item name and press enter"));
VBox root = new VBox(10,
textField,
listenerCombo,
bindingCombo);
root.setPadding(new Insets(10));
root.setAlignment(Pos.CENTER);
primaryStage.setScene(new Scene(root, 250, 350));
primaryStage.show();
}
public static class Item {
private final int id ;
private final String name ;
private final static AtomicInteger nextID = new AtomicInteger(1000);
public Item(String name) {
this.id = nextID.incrementAndGet();
this.name = name;
}
public int getId() {
return id;
}
public String getName() {
return name;
}
}
public static void main(String[] args) {
launch(args);
}
}

JavaFX: TableView row selection

I am working on a java/Javafx project for the first time and i have a TableView with multiple column (name, prename, age...) to present my data and I need the user to be able to select a single row and give me everytime all anformation about the person(Other columns) even when he click at another column but I haven't been able to find the right way to do it.
When i select a row my code give everytime the value of the cell i click on, but i need other informations to search with in my SQLite data base and work on it (Delete/edit this person..)
Here is the code that i use:
...//rest of code
#Override
public void initialize(URL location, ResourceBundle resources) {
private TableView<Student> tbl_elev=new TableView<Student>();
...
tbl_elev.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<Object>() {
#Override
public void changed(ObservableValue<?> observableValue, Object oldValue, Object newValue) {
//Check whether item is selected and set value of selected item to Label
if (tbl_elev.getSelectionModel().getSelectedItem() != null) {
TableViewSelectionModel<Student> selectionModel = tbl_elev.getSelectionModel();
ObservableList<?> selectedCells = selectionModel.getSelectedCells();
#SuppressWarnings("unchecked")
TablePosition<Object, ?> tablePosition = (TablePosition<Object, ?>) selectedCells.get(0);
Object val = tablePosition.getTableColumn().getCellData(newValue);
System.out.println("Selected Value " + val);
}
}
});
}
... //rest of code
I am waiting for your suggestions and ideas, i dont mind if you suggest another approach because this may be uncompatible (taken from internet) Please if you need any other part of the code just comment, i don't put it all because it is too long to read.. (Sorry of my bad english)

If you specify that the ChangeListener parameters are of type Student you can get use the instance methods from that object:
Here's a Minimal, Complete, and Verifiable example:
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class SSCCE extends Application {
#Override
public void start(Stage stage) {
VBox root = new VBox();
TableView<Student> studentsTable = new TableView<Student>();
HBox studentBox = new HBox();
Label studentHeader = new Label("Student: ");
Label studentInfo = new Label("");
studentBox.getChildren().addAll(studentHeader, studentInfo);
root.getChildren().addAll(studentsTable, studentBox);
// Prepare the columns
TableColumn<Student, String> firstNameCol = new TableColumn<Student, String>(
"First name");
firstNameCol.setCellValueFactory(cellData -> cellData.getValue()
.firstNameProperty());
TableColumn<Student, String> lastNameCol = new TableColumn<Student, String>(
"Last name");
lastNameCol.setCellValueFactory(cellData -> cellData.getValue()
.lastNameProperty());
studentsTable.getSelectionModel().selectedItemProperty()
.addListener(new ChangeListener<Student>() {
// Here's the key part. See how I specify that the
// parameters are of type student. Now you can use the
// instance methods from Student.
#Override
public void changed(
ObservableValue<? extends Student> observable,
Student oldValue, Student newValue ) {
studentInfo.setText(newValue.getFirstName() + " "
+ newValue.getLastName());
// If you want to get the value of a selected student cell at
// anytime, even if it hasn't changed. Just do e.g.
// studentsTable.getSelectionModel().getSelectedItem().getFirstName()
}
});
studentsTable.getColumns().setAll(firstNameCol, lastNameCol);
// Some mock Student objects
Student student1 = new Student("Eric", "Smith");
Student student2 = new Student("Brad", "Jones");
Student student3 = new Student("Logan", "Thorpe");
// Fill the table with students.
studentsTable.getItems().addAll(student1, student2, student3);
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch();
}
// The student class. In this case an inner class to simplify the example. But generally you should never use inner classes.
class Student {
private StringProperty firstName;
private StringProperty lastName;
public Student(String firstName, String lastName) {
this.firstName = new SimpleStringProperty(firstName);
this.lastName = new SimpleStringProperty(lastName);
}
public String getFirstName() {
return firstName.get();
}
public void setFirstName(String firstName) {
this.firstName.set(firstName);
}
public StringProperty firstNameProperty() {
return firstName;
}
public String getLastName() {
return lastName.get();
}
public void setLastName(String lastName) {
this.lastName.set(lastName);
}
public StringProperty lastNameProperty() {
return lastName;
}
}
}

After too many failed attempts and thanks to #Jonatan 's answer the code after i compelete some missing words should be like this:
...//rest of code
#Override
public void initialize(URL location, ResourceBundle resources) {
private TableView<Student> tbl_elev=new TableView<Student>();
...
tbl_elev.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<Student>() {
// Here's the key part. See how I specify that the
// parameters are of type student. Now you can use the
// instance methods from Student.
#Override
public void changed(ObservableValue<? extends Student> observable,Student oldValue, Student newValue){
if(newValue!=null){
System.out.println(newValue.getName() + " "+ newValue.getPrename()+" "+newValue.getNaiss());
}
//you can add any other value from Student class via getter(getAdr,getMail,...)
}
});
}
... //rest of code
Output example:
Jonatan stenbacka 2015-09-11
Those value are ready for use to fetch the data base and specify the needed row in it to work on.
Hope that this help someone one day.
thanks...

issue with this tutorial:Populate a tableview using database in JavaFX

I get a nullpointerxception when following this tutorial:
Populate a tableview using database in JavaFX .
I modified it to make it simpler and fit my needs:
Instead of Usermaster, I have Person object.
while(rs.next()){
Person per = new Person();
per.ClientID.set(rs.getInt(1));
per.FirstName.set(rs.getString(2));
per.LastName.set(rs.getString(3));
The code stops at per.ClientID.set(rs.getInt(1)); due to nullpointerxception.
If I make system.out.println(rs.getInt(1)) (or any other column), I get the value... But it appears that I can't pass it to my object per.
All Person object vars are SimpleString/IntergerProperty type, as shown in the tutorial.
Can someone help me to identify the mistake I made in coding this?
Thank you
**Answer: need to initialize values.
Now I have no errors, but my table is not populating...
Full code:
a) Main App
package tableview;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
public class MainApp extends Application {
public static void main(String[] args) {
// TODO Auto-generated method stub
launch(args);
}
#Override
public void start(Stage primaryStage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("view/FXMLTable.fxml"));
Scene scene = new Scene(root);
primaryStage.setScene(scene);
primaryStage.show();
}
}
Model Class:
package tableview.model;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
public class Person {
public SimpleIntegerProperty ClientID = new SimpleIntegerProperty();
public SimpleStringProperty FirstName = new SimpleStringProperty();
public SimpleStringProperty LastName = new SimpleStringProperty();
public SimpleIntegerProperty getClientID() {
return ClientID;
}
public SimpleStringProperty getFirstname() {
return FirstName;
}
public SimpleStringProperty getLastName() {
return LastName;
}
public IntegerProperty clientIDProperty(){
return ClientID;
}
public StringProperty firstNameProperty(){
return FirstName;
}
public StringProperty lastNameProperty(){
return LastName;
}
}
Controller Class:
package tableview.view;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.fxml.FXML;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import tableview.model.Person;
public class FXMLTableController{
#FXML
public TableView<Person> tableview ;
#FXML
private TableColumn<Person, Number> clientIdColumn;
#FXML
private TableColumn<Person, String> firstNameColumn;
#FXML
private TableColumn<Person, String> lastNameColumn;
#FXML
private void initialize() {
assert tableview != null : "fx:id=\"tableview\" was not injected: check your FXML file 'UserMaster.fxml'.";
clientIdColumn.setCellValueFactory(cellData -> cellData.getValue().
clientIDProperty());
firstNameColumn.setCellValueFactory(cellData -> cellData.getValue()
.firstNameProperty());
lastNameColumn.setCellValueFactory(cellData -> cellData.getValue()
.lastNameProperty());
buildData();
}
private ObservableList<Person> data;
public void buildData(){
data = FXCollections.observableArrayList();
Connection con = null;
try {
Class.forName("org.sqlite.JDBC");
con = DriverManager.getConnection("jdbc:sqlite:tableviewdb.db");
String SQL = "Select * from INFO";
ResultSet rs = con.createStatement().executeQuery(SQL);
while(rs.next()){
Person per = new Person();
per.ClientID.set(rs.getInt("CLIENTID"));
per.FirstName.set(rs.getString("FIRSTNAME"));
per.LastName.set(rs.getString("LASTNAME"));
data.add(per);
}
tableview = new TableView<Person>();
tableview.setItems(data);
System.out.println(tableview.getItems().get(1).ClientID);
}
catch(Exception e){
e.printStackTrace();
System.out.println("Error on Building Data");
}
}
}

ClientID is null. You didn't initialize it.
If it's a property, you should create the proper getter and setters for it and not use the property directly. Besides you should never use 1, 2, etc in the ResultSet's getter. It's better practice to use the column names.