使用tableview绑定hashmap(JavaFX)

Question

我想HashMap在JavaFX中显示内容Tableview.请在下面找到我用来将HashMap内容设置到表格列中的代码.我遇到的问题是它只显示一行.所述for环路迭代只有5次:在每次拾取的第一个值的时间HashMap.

如果我忽略该return SimpleObjectProperty行,则for循环将遍历所有内容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

1. CellFactory.Callback.call() 只创建一个单元格,而不是循环中的所有单元格
2. return从循环中使用会中断循环执行.

看看下一个例子,特别是评论:

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();
    }
}