Why are JavaFX2.2 buttons in my table view code not visible? - javafx-2

Question

The JavaFX2 tutorial has an Addressbook example which is a table view.
tutorial:
http://docs.oracle.com/javafx/2/fxml_get_started/fxml_tutorial_intermediate.htm#CACFEHBI
enhancement to edit cells:
http://docs.oracle.com/javafx/2/ui_controls/table-view.htm
modification to add checkbox:
http://download.oracle.com/otndocs/products/javafx/2.2/samples/Ensemble/index.html#SAMPLES/Controls/Table/Table Cell Factory
Entering data in the text boxes and Clicking the Add button adds a row to the table.
However, rows cannot be deleted.
I was trying to see if I can add a Delete button in each cell - clicking it will delete the row.
I modified the existing sample code.
Somehow, the buttons are not visible. Any pointers appreciated.
//FXML_tableview.fxml file
<?import javafx.collections.*?>
<?import javafx.geometry.Insets?>
<?import java.lang.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.control.cell.*?>
<?import javafx.scene.layout.*?>
<?import fxmltableview.*?>
<Scene fx:id="root" width="550" height="550"
fx:controller="fxmltableview.FXMLTableViewController"
xmlns:fx="http://javafx.com/fxml">
<GridPane alignment="center" hgap="10" vgap="10">
<padding>
<Insets top="10" right="10" bottom="10" left="10"/>
</padding>
<TableView fx:id="tableView" GridPane.columnIndex="0"
GridPane.rowIndex="1">
</TableView>
<HBox spacing="10" alignment="bottom_right" GridPane.columnIndex="0"
GridPane.rowIndex="2">
<TextField fx:id="firstNameField" promptText="First Name"
prefWidth="90"/>
<TextField fx:id="lastNameField" promptText="Last Name"
prefWidth="90"/>
<TextField fx:id="emailField" promptText="Email"
prefWidth="150"/>
<Button text="Add" onAction="#addPerson"/>
</HBox>
</GridPane>
</Scene>
// FXMLTableView.java
package fxmltableview;
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.stage.Stage;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.geometry.Pos;
import javafx.scene.control.Button;
import javafx.scene.control.CheckBox;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableColumn.CellEditEvent;
import javafx.scene.control.TableView;
import javafx.scene.control.TextField;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.AnchorPane;
import javafx.util.Callback;
public class FXMLTableView extends Application {
static public ObservableList<Person> data;
#FXML Scene root;
#FXML TableView tableView;
#Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("FXML TableView Example");
root = (Scene)FXMLLoader.load(getClass().getResource("fxml_tableview.fxml"));
primaryStage.setScene(root);
data = FXCollections.observableArrayList(
new Person(true, "Jacob", "Smith", "jacob.smith#example.com"),
new Person(false, "Isabella", "Johnson", "isabella.johnson#example.com"),
new Person(true, "Ethan", "Williams", "ethan.williams#example.com"),
new Person(true, "Emma", "Jones", "emma.jones#example.com"),
new Person(false, "Michael", "Brown", "michael.brown#example.com"));
tableView = (TableView) root.lookup("#tableView");
TableColumn delCol = new TableColumn<Person, Boolean>();
delCol.setMinWidth(50);
delCol.setCellFactory(new Callback<TableColumn<Person, Boolean>, TableCell<Person, Boolean>>() {
public TableCell<Person, Boolean> call(TableColumn<Person, Boolean> p) {
return new DeleteTableCell<Person, Boolean>();
}
});
//"Invited" column
TableColumn invitedCol = new TableColumn<Person, Boolean>();
invitedCol.setText("Invited");
invitedCol.setMinWidth(50);
invitedCol.setCellValueFactory(new PropertyValueFactory("invited"));
invitedCol.setCellFactory(new Callback<TableColumn<Person, Boolean>, TableCell<Person, Boolean>>() {
public TableCell<Person, Boolean> call(TableColumn<Person, Boolean> p) {
return new CheckBoxTableCell<Person, Boolean>();
}
});
//"First Name" column
TableColumn firstNameCol = new TableColumn();
firstNameCol.setText("First");
firstNameCol.setCellValueFactory(new PropertyValueFactory("firstName"));
//"Last Name" column
TableColumn lastNameCol = new TableColumn();
lastNameCol.setText("Last");
lastNameCol.setCellValueFactory(new PropertyValueFactory("lastName"));
//"Email" column
TableColumn emailCol = new TableColumn();
emailCol.setText("Email");
emailCol.setMinWidth(200);
emailCol.setCellValueFactory(new PropertyValueFactory("email"));
//Set cell factory for cells that allow editing
Callback<TableColumn, TableCell> cellFactory =
new Callback<TableColumn, TableCell>() {
public TableCell call(TableColumn p) {
return new EditingCell();
}
};
emailCol.setCellFactory(cellFactory);
firstNameCol.setCellFactory(cellFactory);
lastNameCol.setCellFactory(cellFactory);
//Set handler to update ObservableList properties. Applicable if cell is edited
updateObservableListProperties(emailCol, firstNameCol, lastNameCol);
tableView.setItems(data);
//Enabling editing
tableView.setEditable(true);
tableView.getColumns().addAll(invitedCol, firstNameCol, lastNameCol, emailCol, delCol);
// root.getChildren().add(tableView);
primaryStage.show();
}
private void updateObservableListProperties(TableColumn emailCol, TableColumn firstNameCol,
TableColumn lastNameCol) {
//Modifying the email property in the ObservableList
emailCol.setOnEditCommit(new EventHandler<TableColumn.CellEditEvent<Person, String>>() {
#Override public void handle(TableColumn.CellEditEvent<Person, String> t) {
((Person) t.getTableView().getItems().get(
t.getTablePosition().getRow())).setEmail(t.getNewValue());
}
});
//Modifying the firstName property in the ObservableList
firstNameCol.setOnEditCommit(new EventHandler<TableColumn.CellEditEvent<Person, String>>() {
#Override public void handle(TableColumn.CellEditEvent<Person, String> t) {
((Person) t.getTableView().getItems().get(
t.getTablePosition().getRow())).setFirstName(t.getNewValue());
}
});
//Modifying the lastName property in the ObservableList
lastNameCol.setOnEditCommit(new EventHandler<TableColumn.CellEditEvent<Person, String>>() {
#Override public void handle(TableColumn.CellEditEvent<Person, String> t) {
((Person) t.getTableView().getItems().get(
t.getTablePosition().getRow())).setLastName(t.getNewValue());
}
});
}
//CheckBoxTableCell for creating a CheckBox in a table cell
public static class CheckBoxTableCell<S, T> extends TableCell<S, T> {
private final CheckBox checkBox;
private ObservableValue<T> ov;
public CheckBoxTableCell() {
this.checkBox = new CheckBox();
this.checkBox.setAlignment(Pos.CENTER);
setAlignment(Pos.CENTER);
setGraphic(checkBox);
}
#Override public void updateItem(T item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
setGraphic(checkBox);
if (ov instanceof BooleanProperty) {
checkBox.selectedProperty().unbindBidirectional((BooleanProperty) ov);
}
ov = getTableColumn().getCellObservableValue(getIndex());
if (ov instanceof BooleanProperty) {
checkBox.selectedProperty().bindBidirectional((BooleanProperty) ov);
}
}
}
}
public static class DeleteTableCell<S, T> extends TableCell<S, T> {
private final Button del;
private ObservableValue<T> ov;
public DeleteTableCell() {
this.del = new Button("X");
del.setStyle("-fx-base: red;");
this.del.setAlignment(Pos.CENTER);
setAlignment(Pos.CENTER);
setGraphic(del);
del.setOnAction(new EventHandler<ActionEvent> () {
#Override
public void handle(ActionEvent t) {
int i= getIndex();
FXMLTableView.data.remove(i);
}
});
}
#Override public void updateItem(T item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
setGraphic(del);
}
}
}
// EditingCell - for editing capability in a TableCell
public static class EditingCell extends TableCell<Person, String> {
private TextField textField;
public EditingCell() {
}
#Override public void startEdit() {
super.startEdit();
if (textField == null) {
createTextField();
}
setText(null);
setGraphic(textField);
textField.selectAll();
}
#Override public void cancelEdit() {
super.cancelEdit();
setText((String) getItem());
setGraphic(null);
}
#Override public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (isEditing()) {
if (textField != null) {
textField.setText(getString());
}
setText(null);
setGraphic(textField);
} else {
setText(getString());
setGraphic(null);
}
}
}
private void createTextField() {
textField = new TextField(getString());
textField.setMinWidth(this.getWidth() - this.getGraphicTextGap() * 2);
textField.setOnKeyReleased(new EventHandler<KeyEvent>() {
#Override public void handle(KeyEvent t) {
if (t.getCode() == KeyCode.ENTER) {
commitEdit(textField.getText());
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
}
});
}
private String getString() {
return getItem() == null ? "" : getItem().toString();
}
}
public static void main(String[] args) {
launch(args);
}
}
// FXMLTableViewController.java
package fxmltableview;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.TextField;
public class FXMLTableViewController {
#FXML private TableView<Person> tableView;
#FXML private TextField firstNameField;
#FXML private TextField lastNameField;
#FXML private TextField emailField;
#FXML
protected void addPerson(ActionEvent event) {
ObservableList<Person> data = tableView.getItems();
data.add(new Person(false, firstNameField.getText(),
lastNameField.getText(),
emailField.getText()
));
firstNameField.setText("");
lastNameField.setText("");
emailField.setText("");
}
}
// Person.java
package fxmltableview;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
//Person object
public class Person {
private BooleanProperty invited;
private StringProperty firstName;
private StringProperty lastName;
private StringProperty email;
Person(boolean invited, String fName, String lName, String email) {
this.invited = new SimpleBooleanProperty(invited);
this.firstName = new SimpleStringProperty(fName);
this.lastName = new SimpleStringProperty(lName);
this.email = new SimpleStringProperty(email);
this.invited = new SimpleBooleanProperty(invited);
this.invited.addListener(new ChangeListener<Boolean>() {
public void changed(ObservableValue<? extends Boolean> ov, Boolean t, Boolean t1) {
System.out.println(firstNameProperty().get() + " invited: " + t1);
}
});
}
public BooleanProperty invitedProperty() { return invited; }
public StringProperty firstNameProperty() { return firstName; }
public StringProperty lastNameProperty() { return lastName; }
public StringProperty emailProperty() { return email; }
public void setLastName(String lastName) { this.lastName.set(lastName); }
public void setFirstName(String firstName) { this.firstName.set(firstName); }
public void setEmail(String email) { this.email.set(email); }
}

Answer 1

The delCol's cell value factory is missing. Add
delCol.setCellValueFactory(new PropertyValueFactory("invited"));
PropertyValueFactory's parameter is not important here.