如何從具有javafx中對象的數組列表的對象創建組合框？

Question

如果我有了對象的ArrayList對象：

class Event{   
    private ArrayList<Room> rooms; 
    //.. 
    public void setRooms(ArrayList<Room> rooms) { 
     this.rooms = rooms; 
    } 

    public ArrayList<Room> getRooms() { 
     return rooms; 
    } 
} 

// ---------------------

class Room{ 
    private String roomId; 
    private String roomName; 

    public Room(String roomId, String roomName) { 
     this.roomId = roomId; 
     this.roomName = roomName; 
    } 

    public String getRoomId() { 
     return roomId; 
    } 

    public String getRoomName() { 
     return roomName; 
    } 

    public void setRoomId(String roomId) { 
     this.roomId = roomId; 
    } 

    public void setRoomName(String roomName) { 
     this.roomName = roomName; 
    } 
} 

如何從房間對象數組中創建組合框中的組合框？

我只是顯示某種對象標識符。

TableColumn<Event, ArrayList> roomsColumn = new TableColumn<>("Room Select"); 
roomsColumn.setMinWidth(200); 
roomsColumn.setCellValueFactory(new PropertyValueFactory<>("rooms")); 

//Create an observable list to populate the table with. 
ObservableList<Event> eventList = FXCollections.observableArrayList(); 

//loop the json to populate the observable list 
for (Event event : events.getEventList()){ 
    eventList.add(event); 
} 

//populate the table 
eventTable.setItems(eventList); 
eventTable.getColumns().addAll(eventColumn, bDateColumn, eDateColumn, roomsColumn); 

**所有列都建，但房間欄顯示一個逗號分隔的房間列表對象：

com.***.Room@345, com.***.Room@653, com.***.Room@889 

Answer 1

你需要一個定製的電池工廠與組合框返回的TableCell。

roomsColumn.setCellFactory(call -> { 
     // create a new cell for array lists 
     return new TableCell<Event, ArrayList<String>>() { 
      @Override 
      protected void updateItem(ArrayList<String> item, boolean empty) { 
       super.updateItem(item, empty); 
       // if there is no item, return an empty cell 
       if (empty || item == null) { 
        setGraphic(null); 
       } 
       else { 
        ComboBox<String> box = new ComboBox<>(); 
        // set combo box items 
        box.setItems(FXCollections.observableArrayList(item)); 
        // listen for changes 
        box.valueProperty().addListener((observable, oldValue, newValue) -> { 
         System.out.println("new room "+newValue); 
        }); 
        // set cell contents 
        setGraphic(box); 
       } 
      } 
     }; 
    });