我正在调查Tree Table View用户界面组件,因为我想在我的javaFX应用程序中实现它。
以下是TreeTableView
类的示例oracle代码:
import java.util.Arrays;
import java.util.List;
import javafx.application.Application;
import javafx.beans.property.ReadOnlyStringWrapper;
import javafx.beans.property.SimpleStringProperty;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.TreeTableColumn;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeTableView;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
public class TreeTableViewSample extends Application {
List<Employee> employees = Arrays.<Employee>asList(
new Employee("Ethan Williams", "ethan.williams@example.com"),
new Employee("Emma Jones", "emma.jones@example.com"),
new Employee("Michael Brown", "michael.brown@example.com"),
new Employee("Anna Black", "anna.black@example.com"),
new Employee("Rodger York", "roger.york@example.com"),
new Employee("Susan Collins", "susan.collins@example.com"));
private final ImageView depIcon = new ImageView (
new Image(getClass().getResourceAsStream("department.png"))
);
final TreeItem<Employee> root =
new TreeItem<>(new Employee("Sales Department", ""), depIcon);
public static void main(String[] args) {
Application.launch(TreeTableViewSample.class, args);
}
@Override
public void start(Stage stage) {
root.setExpanded(true);
employees.stream().forEach((employee) -> {
root.getChildren().add(new TreeItem<>(employee));
});
stage.setTitle("Tree Table View Sample");
final Scene scene = new Scene(new Group(), 400, 400);
scene.setFill(Color.LIGHTGRAY);
Group sceneRoot = (Group) scene.getRoot();
TreeTableColumn<Employee, String> empColumn =
new TreeTableColumn<>("Employee");
empColumn.setPrefWidth(150);
empColumn.setCellValueFactory(
(TreeTableColumn.CellDataFeatures<Employee, String> param) ->
new ReadOnlyStringWrapper(param.getValue().getValue().getName())
);
TreeTableColumn<Employee, String> emailColumn =
new TreeTableColumn<>("Email");
emailColumn.setPrefWidth(190);
emailColumn.setCellValueFactory(
(TreeTableColumn.CellDataFeatures<Employee, String> param) ->
new ReadOnlyStringWrapper(param.getValue().getValue().getEmail())
);
TreeTableView<Employee> treeTableView = new TreeTableView<>(root);
treeTableView.getColumns().setAll(empColumn, emailColumn);
sceneRoot.getChildren().add(treeTableView);
stage.setScene(scene);
stage.show();
}
public class Employee {
private SimpleStringProperty name;
private SimpleStringProperty email;
public SimpleStringProperty nameProperty() {
if (name == null) {
name = new SimpleStringProperty(this, "name");
}
return name;
}
public SimpleStringProperty emailProperty() {
if (email == null) {
email = new SimpleStringProperty(this, "email");
}
return email;
}
private Employee(String name, String email) {
this.name = new SimpleStringProperty(name);
this.email = new SimpleStringProperty(email);
}
public String getName() {
return name.get();
}
public void setName(String fName) {
name.set(fName);
}
public String getEmail() {
return email.get();
}
public void setEmail(String fName) {
email.set(fName);
}
}
}
这里唯一的问题是我正在开发兼容java7的版本,而下面的lambda表达式只受java8支持:
emailColumn.setCellValueFactory(
(TreeTableColumn.CellDataFeatures<Employee, String> param) ->
new ReadOnlyStringWrapper(param.getValue().getValue().getEmail())
);
如何实现此类以便JRE7支持它?
我还是lambda表达式的新手,因为我一直在研究JRE7环境的java应用程序,所以我真的不知道如何将lambda表达式“转换”为它们的“非lambda”等价物。