Dynamically adding data in Hashmap to TableView in JavaFX - callback

Question

I have a map mapping symbols to prices.I want to display a table with one column containing keys and the other column containing corresponding values in JavaFX
public class myMap {
Map<Symbol, Price> map;
}
I want to display a table like the following
Symbol | Price
I guess it can be done by using TableView with CallBack.

Answer 1

Since I've already done something similar to this I'll add my code.
import java.util.Map;
import javafx.application.Application;
import javafx.beans.property.ReadOnlyObjectWrapper;
import javafx.beans.property.SimpleStringProperty;
import javafx.collections.FXCollections;
import javafx.collections.MapChangeListener;
import javafx.collections.ObservableMap;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.TextFieldTableCell;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.converter.NumberStringConverter;
public class MapTable extends Application {
#Override
public void start(Stage primaryStage) {
final ObservableMap<String, Number> obsMap = FXCollections.observableHashMap();
for (int i = 0; i < 3; i++) obsMap.put("key "+i, i*10d);
final TableView<ObservableMap.Entry<String, Number>> tv = new TableView(FXCollections.observableArrayList(obsMap.entrySet()));
tv.setEditable(true);
obsMap.addListener((MapChangeListener.Change<? extends String, ? extends Number> change) -> {
tv.setItems(FXCollections.observableArrayList(obsMap.entrySet()));
});
TableColumn<ObservableMap.Entry<String, Number>,String> keyCol = new TableColumn<>("key");
TableColumn<ObservableMap.Entry<String, Number>,Number> priceCol = new TableColumn<>("price");
tv.getColumns().addAll(keyCol,priceCol);
keyCol.setCellValueFactory((p) -> {
return new SimpleStringProperty(p.getValue().getKey());
});
keyCol.setCellFactory(TextFieldTableCell.forTableColumn());
keyCol.setOnEditCommit((TableColumn.CellEditEvent<Map.Entry<String,Number>, String> t) -> {
final String oldKey = t.getOldValue();
final Number oldPrice = obsMap.get(oldKey);
obsMap.remove(oldKey);
obsMap.put(t.getNewValue(),oldPrice);
});
priceCol.setCellValueFactory((p) -> {
return new ReadOnlyObjectWrapper<>(p.getValue().getValue());
});
priceCol.setCellFactory(TextFieldTableCell.forTableColumn(new NumberStringConverter()));
priceCol.setOnEditCommit((TableColumn.CellEditEvent<Map.Entry<String,Number>, Number> t) -> {
obsMap.put(t.getTableView().getItems().get(t.getTablePosition().getRow()).getKey(),//key
t.getNewValue());//val);
});
Button btn1 = new Button();
btn1.setText("Add data");
btn1.setOnAction((ActionEvent event) -> {
obsMap.put("hi",100);
});
Button btn2 = new Button();
btn2.setText("verify data");
btn2.setOnAction((ActionEvent event) -> {
for (Map.Entry<String,Number> me : obsMap.entrySet())
System.out.println("key "+me.getKey()+" val "+me.getValue());
});
VBox root = new VBox(tv,btn1,btn2);
Scene scene = new Scene(root, 300, 250);
primaryStage.setTitle("Map Table test");
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}

Answer 2

Hope this can help.
public class Demo {
public static void main(String[] args) {
// Use Java Collections to create the List.
Map<String,String> map = new HashMap<String,String>();
// Now add observability by wrapping it with ObservableList.
ObservableMap<String,String> observableMap = FXCollections.observableMap(map);
observableMap.addListener(new MapChangeListener() {
#Override
public void onChanged(MapChangeListener.Change change) {
System.out.println("Detected a change! ");
}
});
// Changes to the observableMap WILL be reported.
observableMap.put("key 1","value 1");
System.out.println("Size: "+observableMap.size());
// Changes to the underlying map will NOT be reported.
map.put("key 2","value 2");
System.out.println("Size: "+observableMap.size());
}
}
http://docs.oracle.com/javafx/2/collections/jfxpub-collections.htm