TreeView UI控件為我們提供了一種渲染樹結(jié)構(gòu)的方法。 樹具有包含所有分層值的根節(jié)點(diǎn)。
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class Main extends Application {
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage primaryStage) {
TreeItem<String> rootItem = new TreeItem<>("Root");
rootItem.setExpanded(true);
TreeItem<String> item = new TreeItem<>("A");
rootItem.getChildren().add(item);
item = new TreeItem<>("B");
rootItem.getChildren().add(item);
TreeView<String> tree = new TreeView<>(rootItem);
StackPane root = new StackPane();
root.getChildren().add(tree);
primaryStage.setScene(new Scene(root, 300, 250));
primaryStage.show();
}
}
上面的代碼生成以下結(jié)果。
當(dāng)創(chuàng)建樹視圖時,我們通常從構(gòu)建根的TreeItem對象開始。 然后我們將根添加到樹視圖,并創(chuàng)建其他樹項(xiàng)目對象并將它們添加到根。
我們可以通過setGraphic方法或使用它的構(gòu)造函數(shù)來創(chuàng)建一個圖形圖標(biāo)到樹項(xiàng)目。 圖標(biāo)的建議大小為16x16。
對根項(xiàng)目調(diào)用的setExpanded方法定義樹視圖項(xiàng)目的初始外觀。
以下代碼從本地文件系統(tǒng)創(chuàng)建動態(tài)樹。
import java.io.File;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Main extends Application {
public static void main(String[] args) {
launch(args);
}
private TreeItem<File> createNode(final File f) {
return new TreeItem<File>(f) {
private boolean isLeaf;
private boolean isFirstTimeChildren = true;
private boolean isFirstTimeLeaf = true;
@Override
public ObservableList<TreeItem<File>> getChildren() {
if (isFirstTimeChildren) {
isFirstTimeChildren = false;
super.getChildren().setAll(buildChildren(this));
}
return super.getChildren();
}
@Override
public boolean isLeaf() {
if (isFirstTimeLeaf) {
isFirstTimeLeaf = false;
File f = (File) getValue();
isLeaf = f.isFile();
}
return isLeaf;
}
private ObservableList<TreeItem<File>> buildChildren(
TreeItem<File> TreeItem) {
File f = TreeItem.getValue();
if (f == null) {
return FXCollections.emptyObservableList();
}
if (f.isFile()) {
return FXCollections.emptyObservableList();
}
File[] files = f.listFiles();
if (files != null) {
ObservableList<TreeItem<File>> children = FXCollections
.observableArrayList();
for (File childFile : files) {
children.add(createNode(childFile));
}
return children;
}
return FXCollections.emptyObservableList();
}
};
}
@Override
public void start(Stage stage) {
Scene scene = new Scene(new Group(), 300, 300);
VBox vbox = new VBox();
TreeItem<File> root = createNode(new File("c:/"));
TreeView treeView = new TreeView<File>(root);
vbox.getChildren().add(treeView);
((Group) scene.getRoot()).getChildren().add(vbox);
stage.setScene(scene);
stage.show();
}
}
上面的代碼生成以下結(jié)果。
以下代碼顯示了如何使用用戶域模型數(shù)據(jù)與TreeView。
創(chuàng)建Employee類以捕獲用戶域模型,并且代碼使用循環(huán)將所有員工添加到樹視圖。
/*
* Copyright (c) 2008, 2014, Oracle and/or its affiliates.
* All rights reserved. Use is subject to license terms.
*
* This file is available and licensed under the following license:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the distribution.
* - Neither the name of Oracle nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
import java.util.Arrays;
import java.util.List;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
public class Main extends Application {
List<Employee> employees = Arrays.<Employee>asList(
new Employee("a1", "A"),
new Employee("a2", "A"),
new Employee("e1", "E"));
private final Node rootIcon = new ImageView(new Image(getClass().getResourceAsStream("root.png")));
TreeItem<String> rootNode = new TreeItem<String>("Root",rootIcon);
public static void main(String[] args) {
Application.launch(args);
}
@Override
public void start(Stage stage) {
rootNode.setExpanded(true);
for (Employee employee : employees) {
TreeItem<String> empLeaf = new TreeItem<String>(employee.getName());
boolean found = false;
for (TreeItem<String> depNode : rootNode.getChildren()) {
if (depNode.getValue().contentEquals(employee.getDepartment())){
depNode.getChildren().add(empLeaf);
found = true;
break;
}
}
if (!found) {
TreeItem depNode = new TreeItem(employee.getDepartment());
rootNode.getChildren().add(depNode);
depNode.getChildren().add(empLeaf);
}
}
stage.setTitle("Tree View Sample");
VBox box = new VBox();
final Scene scene = new Scene(box, 400, 300);
scene.setFill(Color.LIGHTGRAY);
TreeView<String> treeView = new TreeView<String>(rootNode);
treeView.setShowRoot(true);
treeView.setEditable(true);
box.getChildren().add(treeView);
stage.setScene(scene);
stage.show();
}
public static class Employee {
private final SimpleStringProperty name;
private final SimpleStringProperty department;
private Employee(String name, String department) {
this.name = new SimpleStringProperty(name);
this.department = new SimpleStringProperty(department);
}
public String getName() {
return name.get();
}
public void setName(String fName) {
name.set(fName);
}
public String getDepartment() {
return department.get();
}
public void setDepartment(String fName) {
department.set(fName);
}
}
}
/*
* Copyright (c) 2008, 2014, Oracle and/or its affiliates.
* All rights reserved. Use is subject to license terms.
*
* This file is available and licensed under the following license:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the distribution.
* - Neither the name of Oracle nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
import java.util.Arrays;
import java.util.List;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.MenuItem;
import javafx.scene.control.TextField;
import javafx.scene.control.TreeCell;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
public class Main extends Application {
List<Employee> employees = Arrays.<Employee>asList(
new Employee("Jacob Smith", "Accounts Department"),
new Employee("Judy Mayer", "IT Support"),
new Employee("Gregory Smith", "IT Support"));
TreeItem<String> rootNode =
new TreeItem<>("MyCompany Human Resources");
public static void main(String[] args) {
Application.launch(args);
}
@Override
public void start(Stage stage) {
rootNode.setExpanded(true);
for (Employee employee : employees) {
TreeItem<String> empLeaf = new TreeItem<>(employee.getName());
boolean found = false;
for (TreeItem<String> depNode : rootNode.getChildren()) {
if (depNode.getValue().contentEquals(employee.getDepartment())){
depNode.getChildren().add(empLeaf);
found = true;
break;
}
}
if (!found) {
TreeItem depNode = new TreeItem(employee.getDepartment());
rootNode.getChildren().add(depNode);
depNode.getChildren().add(empLeaf);
}
}
stage.setTitle("Tree View Sample");
VBox box = new VBox();
final Scene scene = new Scene(box, 400, 300);
scene.setFill(Color.LIGHTGRAY);
TreeView<String> treeView = new TreeView<>(rootNode);
treeView.setEditable(true);
treeView.setCellFactory((TreeView<String> p) ->
new TextFieldTreeCellImpl());
box.getChildren().add(treeView);
stage.setScene(scene);
stage.show();
}
private final class TextFieldTreeCellImpl extends TreeCell<String> {
private TextField textField;
private final ContextMenu addMenu = new ContextMenu();
public TextFieldTreeCellImpl() {
MenuItem addMenuItem = new MenuItem("Add Employee");
addMenu.getItems().add(addMenuItem);
addMenuItem.setOnAction((ActionEvent t) -> {
TreeItem newEmployee =
new TreeItem<>("New Employee");
getTreeItem().getChildren().add(newEmployee);
});
}
@Override
public void startEdit() {
super.startEdit();
if (textField == null) {
createTextField();
}
setText(null);
setGraphic(textField);
textField.selectAll();
}
@Override
public void cancelEdit() {
super.cancelEdit();
setText((String) getItem());
setGraphic(getTreeItem().getGraphic());
}
@Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (isEditing()) {
if (textField != null) {
textField.setText(getString());
}
setText(null);
setGraphic(textField);
} else {
setText(getString());
setGraphic(getTreeItem().getGraphic());
if (
!getTreeItem().isLeaf()&&getTreeItem().getParent()!= null
){
setContextMenu(addMenu);
}
}
}
}
private void createTextField() {
textField = new TextField(getString());
textField.setOnKeyReleased((KeyEvent t) -> {
if (t.getCode() == KeyCode.ENTER) {
commitEdit(textField.getText());
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
});
}
private String getString() {
return getItem() == null ? "" : getItem().toString();
}
}
public static class Employee {
private final SimpleStringProperty name;
private final SimpleStringProperty department;
private Employee(String name, String department) {
this.name = new SimpleStringProperty(name);
this.department = new SimpleStringProperty(department);
}
public String getName() {
return name.get();
}
public void setName(String fName) {
name.set(fName);
}
public String getDepartment() {
return department.get();
}
public void setDepartment(String fName) {
department.set(fName);
}
}
}
上面的代碼生成以下結(jié)果。
單元工廠可以向TreeView中的單個TreeItem添加具有特殊功能的TreeCell。
/*
* Copyright (c) 2008, 2014, Oracle and/or its affiliates.
* All rights reserved. Use is subject to license terms.
*
* This file is available and licensed under the following license:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the distribution.
* - Neither the name of Oracle nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
import java.util.Arrays;
import java.util.List;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.control.TreeCell;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
public class Main extends Application {
List<Employee> employees = Arrays.<Employee> asList(new Employee(
"Jacob Smith", "Accounts Department"), new Employee("Isabella Johnson",
"Accounts Department"), new Employee("Mike Graham", "IT Support"),
new Employee("Judy Mayer", "IT Support"), new Employee("Gregory Smith",
"IT Support"));
TreeItem<String> rootNode;
public static void main(String[] args) {
Application.launch(args);
}
public Main() {
this.rootNode = new TreeItem<>("MyCompany Human Resources");
}
@Override
public void start(Stage stage) {
rootNode.setExpanded(true);
for (Employee employee : employees) {
TreeItem<String> empLeaf = new TreeItem<>(employee.getName());
boolean found = false;
for (TreeItem<String> depNode : rootNode.getChildren()) {
if (depNode.getValue().contentEquals(employee.getDepartment())) {
depNode.getChildren().add(empLeaf);
found = true;
break;
}
}
if (!found) {
TreeItem<String> depNode = new TreeItem<>(employee.getDepartment());
rootNode.getChildren().add(depNode);
depNode.getChildren().add(empLeaf);
}
}
stage.setTitle("Tree View Sample");
VBox box = new VBox();
final Scene scene = new Scene(box, 400, 300);
scene.setFill(Color.LIGHTGRAY);
TreeView<String> treeView = new TreeView<>(rootNode);
treeView.setEditable(true);
treeView
.setCellFactory((TreeView<String> p) -> new TextFieldTreeCellImpl());
box.getChildren().add(treeView);
stage.setScene(scene);
stage.show();
}
private final class TextFieldTreeCellImpl extends TreeCell<String> {
private TextField textField;
public TextFieldTreeCellImpl() {
}
@Override
public void startEdit() {
super.startEdit();
if (textField == null) {
createTextField();
}
setText(null);
setGraphic(textField);
textField.selectAll();
}
@Override
public void cancelEdit() {
super.cancelEdit();
setText((String) getItem());
setGraphic(getTreeItem().getGraphic());
}
@Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (isEditing()) {
if (textField != null) {
textField.setText(getString());
}
setText(null);
setGraphic(textField);
} else {
setText(getString());
setGraphic(getTreeItem().getGraphic());
}
}
}
private void createTextField() {
textField = new TextField(getString());
textField.setOnKeyReleased((KeyEvent t) -> {
if (t.getCode() == KeyCode.ENTER) {
commitEdit(textField.getText());
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
});
}
private String getString() {
return getItem() == null ? "" : getItem().toString();
}
}
public static class Employee {
private final SimpleStringProperty name;
private final SimpleStringProperty department;
private Employee(String name, String department) {
this.name = new SimpleStringProperty(name);
this.department = new SimpleStringProperty(department);
}
public String getName() {
return name.get();
}
public void setName(String fName) {
name.set(fName);
}
public String getDepartment() {
return department.get();
}
public void setDepartment(String fName) {
department.set(fName);
}
}
}
上面的代碼生成以下結(jié)果。
我們可以使用以下樹單元編輯器。
有些類擴(kuò)展了TreeCell實(shí)現(xiàn)來渲染單元格內(nèi)的特定控件。
下面的代碼創(chuàng)建一個帶有復(fù)選框樹項(xiàng)目的樹視圖。
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.CheckBoxTreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.control.cell.CheckBoxTreeCell;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class Main extends Application {
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage primaryStage) {
CheckBoxTreeItem<String> rootItem = new CheckBoxTreeItem<>("A");
rootItem.setExpanded(true);
TreeView tree = new TreeView(rootItem);
tree.setEditable(true);
tree.setCellFactory(CheckBoxTreeCell.forTreeView());
CheckBoxTreeItem<String> checkBoxTreeItem = new CheckBoxTreeItem<>("a");
rootItem.getChildren().add(checkBoxTreeItem);
checkBoxTreeItem = new CheckBoxTreeItem<>("b");
rootItem.getChildren().add(checkBoxTreeItem);
tree.setRoot(rootItem);
StackPane root = new StackPane();
root.getChildren().add(tree);
primaryStage.setScene(new Scene(root, 300, 250));
primaryStage.show();
}
}
上面的代碼生成以下結(jié)果。
更多建議: