问题
so i have a table view with 3 columns and one of them is a column of comboboxes, the way i create the column of combobox is as so
Source = new TableColumn<>("Configure Interface as..");
Source.setCellValueFactory(i -> {
final StringProperty value = i.getValue().optionProperty();
// binding to constant value
return Bindings.createObjectBinding(() -> value);
});
Source.setCellFactory(col -> {
TableCell<TableViewTest, StringProperty> c = new TableCell<>();
ComboBox<String> comboBox = new ComboBox<>(options);
c.itemProperty().addListener((observable, oldValue, newValue) -> {
if (oldValue != null) {
comboBox.valueProperty().unbindBidirectional(oldValue);
}
if (newValue != null) {
comboBox.valueProperty().bindBidirectional(newValue);
}
});
c.graphicProperty().bind(Bindings.when(c.emptyProperty()).then((Node) null).otherwise(comboBox));
return c;
});
the column gets its values from the getter method optionProperty() which resides within my TableViewTest class.
So the problem i'm having is I have another combobox (comboBoxA) that is above my tableview table in my gui, and when ever i change the value of comboBoxA i want to change the values of the comboboxes with the column.
I can do this by calling the following code within the method that is listening for the selection change of comboboxA
Source.setCellValueFactory(i -> {
final StringProperty value = i.getValue().optionTwoProperty();
// binding to constant value
return Bindings.createObjectBinding(() -> value);
});
but the values don't change unless is start scrolling down to near the bottom of the table. is there a way to force the comboboxes to change to the new values within the getter method optionTwoProperty() without me having to scroll down?.
EDIT
Okay so the line
final StringProperty value = i.getValue().optionTwoProperty();
doesnt actaully get called until i start scrolling down.
回答1:
So, with help from fabian, I think I understand that you want the combo box above the table to change the property in your model class that is represented in the cells in the table column.
One way to do this is to make the type of the combo box function that maps the model class to a property, and populate it with functions mapping to each of the properties you want.
Then you can represent the cell value factory for the table column with a binding that observes all the possible properties that could be represented, along with the selected value in the combo box, and returns the value computed by applying the function from the combo box to the model instance (and retrieving its wrapped value).
For the cell factory for the column, you can observe the selected value in the cell's combo box. When it changes, use the selected item in the combo box above the table to figure out which property to update.
Here's a SSCCE:
import java.util.function.Function;
import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.geometry.Insets;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.ListCell;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class TableWithSetAllComboBox extends Application {
@Override
public void start(Stage primaryStage) {
TableView<Item> table = new TableView<>();
TableColumn<Item, String> itemCol = new TableColumn<>("Item");
itemCol.setCellValueFactory(cellData -> Bindings.createStringBinding(() -> cellData.getValue().getName()));
table.getColumns().add(itemCol);
TableColumn<Item, String> choiceCol = new TableColumn<>("Choice");
ComboBox<Function<Item, StringProperty>> option = new ComboBox<>();
option.getItems().add(Item::choiceProperty);
option.getItems().add(Item::choice2Property);
option.setCellFactory(lv -> createListCell());
option.setButtonCell(createListCell());
option.getSelectionModel().select(0);
ObservableList<String> choices = FXCollections.observableArrayList("First choice", "Second choice", "Third choice");
choiceCol.setCellFactory(col -> {
TableCell<Item, String> cell = new TableCell<>();
ComboBox<String> combo = new ComboBox<>(choices);
cell.graphicProperty().bind(Bindings.when(cell.emptyProperty()).then((Node)null).otherwise(combo));
combo.valueProperty().addListener((obs, oldValue, newValue) -> {
if (! cell.isEmpty() && newValue != null) {
Item item = table.getItems().get(cell.getIndex()) ;
StringProperty property = option.getValue().apply(item);
property.set(newValue);
}
});
cell.itemProperty().addListener((obs, oldItem, newItem) -> combo.setValue(newItem));
return cell ;
});
choiceCol.setPrefWidth(150);
table.getColumns().add(choiceCol);
choiceCol.setCellValueFactory(cellData -> Bindings.createStringBinding(
() -> option.getValue().apply(cellData.getValue()).get(),
cellData.getValue().choiceProperty(),
cellData.getValue().choice2Property(),
option.valueProperty()));
choiceCol.setGraphic(option);
choiceCol.setPrefWidth(200);
for (int i = 1; i <= 30 ; i++) table.getItems().add(new Item("Item "+i ,choices.get(0)));
Button debug = new Button("Debug");
debug.setOnAction(e -> table.getItems().stream().
map(item -> String.format("%s (%s, %s)", item.getName(), item.getChoice(), item.getChoice2())).
forEach(System.out::println));
BorderPane root = new BorderPane(table);
BorderPane.setMargin(debug, new Insets(5));
root.setBottom(debug);
primaryStage.setScene(new Scene(root, 600, 600));
primaryStage.show();
}
private ListCell<Function<Item, StringProperty>> createListCell() {
return new ListCell<Function<Item, StringProperty>>() {
@Override
public void updateItem(Function<Item, StringProperty> item, boolean empty) {
super.updateItem(item, empty);
setText(empty ? null : item.apply(new Item("", "")).getName());
}
};
}
public static class Item {
private final String name ;
private final StringProperty choice ;
private final StringProperty choice2 ;
public Item(String name, String choice) {
this.choice = new SimpleStringProperty(this, "Choice", choice);
this.choice2 = new SimpleStringProperty(this, "Choice 2", "Second choice");
this.name = name ;
}
public final StringProperty choiceProperty() {
return this.choice;
}
public final java.lang.String getChoice() {
return this.choiceProperty().get();
}
public final void setChoice(final java.lang.String choice) {
this.choiceProperty().set(choice);
}
public String getName() {
return name;
}
public final StringProperty choice2Property() {
return this.choice2;
}
public final java.lang.String getChoice2() {
return this.choice2Property().get();
}
public final void setChoice2(final java.lang.String choice2) {
this.choice2Property().set(choice2);
}
}
public static void main(String[] args) {
launch(args);
}
}
回答2:
Hard to say given the code snippets. Maybe you're not on the javaFX thread when doing the update? In that case use Platform.runLater(...), or share some minimal amout of code to reproduce the problem.
回答3:
The issue is the TableView not listening to modifications of the cellValueFactory property of the elements of it's columns. Therefore the TableView doesn't know it should redraw it's cells. In JavaFX 8u60 the refresh() method was added for this purpose (for some reason I can't find it in the online javadoc though), which allows you to change the code of your method changing the cellValueFactory like this:
Source.setCellValueFactory(i -> {
final StringProperty value = i.getValue().optionTwoProperty();
// binding to constant value
return Bindings.createObjectBinding(() -> value);
});
tableview.refresh();
In older versions you have to use the workaround of setting the column value to trigger a change in the list:
List<TableColumn<TableViewTest, ?>> columns = tableview.getColumns();
columns.set(columns.indexOf(Source), Source);
But this workaround could cease to work in future versions, since the list is not actually modified with this operation and triggering a list change event is not required by the contract of ObservableList (but replacing the TableColumn with a new instance (and copying the properties) should always work).
来源：https://stackoverflow.com/questions/35727262/refreshing-a-column-of-comboboxes-in-a-table-view-javafx