Binding hashmap with tableview (JavaFX) - javafx-2

Question

I want to display HashMap contents in a JavaFX Tableview. Please find below the code I used to set the HashMap contents into the table columns. The problem I'm having is that it's displaying only one row. The for loop is iterating only 5 times: each time it is picking up the first value of the HashMap.
If I ignore the return SimpleObjectProperty line, the for loop is iterating over all the content in the HashMap.
final ObservableList<Map> data = FXCollections.observableArrayList();
data.addAll(HASHMAP);
TableColumn<Map.Entry, String> nCol = new TableColumn<Map.Entry, String>("Name");
nCol.setEditable(true);
nCol.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Entry, String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(TableColumn.CellDataFeatures<Entry, String> p) {
Set <String> set=HASHMAP.keySet();
for (String key:HASHMAP.keySet())
{
String key1= key.toString();
return new SimpleObjectProperty<>(key.toString());
}
return null;
}
});
Table.setItems(data);
Table.getColumns().setAll(nCol,.........);

Answer 1

CellFactory.Callback.call() creates just one cell, not all cells in a loop
Using return from a loop breaks loop execution.
Take a look at next example, especially comments:
public class MapTableView extends Application {
#Override
public void start(Stage stage) {
// sample data
Map<String, String> map = new HashMap<>();
map.put("one", "One");
map.put("two", "Two");
map.put("three", "Three");
// use fully detailed type for Map.Entry<String, String>
TableColumn<Map.Entry<String, String>, String> column1 = new TableColumn<>("Key");
column1.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Map.Entry<String, String>, String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(TableColumn.CellDataFeatures<Map.Entry<String, String>, String> p) {
// this callback returns property for just one cell, you can't use a loop here
// for first column we use key
return new SimpleStringProperty(p.getValue().getKey());
}
});
TableColumn<Map.Entry<String, String>, String> column2 = new TableColumn<>("Value");
column2.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Map.Entry<String, String>, String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(TableColumn.CellDataFeatures<Map.Entry<String, String>, String> p) {
// for second column we use value
return new SimpleStringProperty(p.getValue().getValue());
}
});
ObservableList<Map.Entry<String, String>> items = FXCollections.observableArrayList(map.entrySet());
final TableView<Map.Entry<String,String>> table = new TableView<>(items);
table.getColumns().setAll(column1, column2);
Scene scene = new Scene(table, 400, 400);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch();
}
}

Answer 2

Sergey Grinev; I found a solution, a generic solution for this problem
public class TableCassaController<K,V> extends TableView<Map.Entry<K,V>> implements Initializable {
#FXML private TableColumn<K, V> column1;
#FXML private TableColumn<K, V> column2;
public TableCassaController(ObservableMap<K,V> map, String col1Name, String col2Name) {
System.out.println("Costruttore table");
TableColumn<Map.Entry<K, V>, K> column1 = new TableColumn<>(col1Name);
column1.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Map.Entry<K, V>, K>, ObservableValue<K>>() {
#Override
public ObservableValue<K> call(TableColumn.CellDataFeatures<Map.Entry<K, V>, K> p) {
// this callback returns property for just one cell, you can't use a loop here
// for first column we use key
return new SimpleObjectProperty<K>(p.getValue().getKey());
}
});
TableColumn<Map.Entry<K, V>, V> column2 = new TableColumn<>(col2Name);
column2.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<Map.Entry<K, V>, V>, ObservableValue<V>>() {
#Override
public ObservableValue<V> call(TableColumn.CellDataFeatures<Map.Entry<K, V>, V> p) {
// for second column we use value
return new SimpleObjectProperty<V>(p.getValue().getValue());
}
});
ObservableList<Map.Entry<K, V>> items = FXCollections.observableArrayList(map.entrySet());
this.setItems(items);
this.getColumns().setAll(column1, column2);
}
Very Thanks!!! :-)