Accessing Web Services - JavaFX 8: A Definitive Guide to Building Desktop, Mobile, and Embedded Java Clients - page 511

primaryStage.setTitle("StackOverflow Table");
primaryStage.setScene(scene);
primaryStage.show();
}
Clearly, this example requires more code than the example showing a ListView . Setting up a table is slightly
more complex, due to the different columns that are involved. There is not much difference between setting the
contents of the ListView and setting the contents of the TableView . This is achieved doing
tableView.setItems(getObservableList());
where the getObservableList() method is the same implementation as in the previous example. Note that we could
also use the convenient constructor
TableView<Question> tableView = new TableView<>(getObservableList());
When using a TableView , we have to define a number of TableColumns . This is done in the following code snippet.
TableColumn<Question, String> dateColumn = new TableColumn<>("Date");
TableColumn<Question, String> ownerColumn = new TableColumn<>("Owner");
TableColumn<Question, String> questionColumn = new TableColumn<>("Question");
Using the TableColumn constructor, we create one TableColumn with title “Date,” one with title “Owner,” and
a third one titled “Question.” The Generics <Question, String> indicate that each entry in a row represents a
Question , and the individual cells in the specified column are of type String .
Next, the instances of TableColumn that we created need to know what data they should render. This is done
using CellFactories , as shown in the following snippet.
dateColumn.setCellValueFactory((CellDataFeatures<Question, String> cdf) -> {
Question q = cdf.getValue();
return new SimpleStringProperty(getTimeStampString(q.getTimestamp()));
});
A detailed description of the setCellValueFactory method is beyond the scope of this chapter. The reader
is encouraged to have a look at the JavaDoc of the TableView and TableColumn classes while working with tables.
The JavaDoc explains that we have to specify a Callback class with a call method that returns an ObservableValue
containing the content of the specific cell. Fortunately, we can use a lambda expression for this.
The question we are displaying in this row can be obtained via the CellDataFeatures instance that is
passed as the single parameter in this lambda expression. Because we want to show the timestamp, we return a
SimpleStringProperty whose content is set to the timestamp of the specified Question .
The same technique has to be used for the other TableColumns (containing the owner and the question
contained within the applicable Question object).
Finally, we have to add the columns to the TableView :
tableView.getColumns().addAll(dateColumn, ownerColumn, questionColumn);
Running this example results in the visual output shown in Figure 11-7 .