Question

Hi i am working on an application related to treeView in javafx, i asked this question before [1]: JavaFx: How to Use existing branch with leafs as a newly add branch , but didn't get any answer. i tried myself and reached here

public class Main extends Application
{
    private static TreeItem<String> item2;
    @SuppressWarnings("unchecked")
    @Override
    public void start(Stage primaryStage)
    {   
       BorderPane border = new BorderPane();    
        Scene scene = new Scene(border,300,300); 
        primaryStage.setTitle("BorderPane");
        primaryStage.setScene(scene);
        primaryStage.show();    

        TreeItem<String> tree = new TreeItem<String>("Root"); 
         item2 = new TreeItem<String>("poles");
        TreeItem<String>  item2Child1 = new TreeItem<String>("X");
        TreeItem<String> item2Child2 = new TreeItem<String>("Y");
        item2.getChildren().addAll(item2Child1,item2Child2);        
        //item2.setExpanded(true);    
        tree.setExpanded(true);
        tree.getChildren().addAll(item2);
        TreeView<String> treeView  = new TreeView<String>(tree);       
        treeView.setCellFactory(new Callback<TreeView<String>,TreeCell<String>>(){
            @Override
            public TreeCell<String> call(TreeView<String> p) {
                return new AddMenuTreeCell();
            }
        });        
        border.setCenter(treeView);
    }    
    private static class AddMenuTreeCell extends TextFieldTreeCell<String> {
        private ContextMenu menu = new ContextMenu();
        private TextField textField;

        public AddMenuTreeCell() {
            MenuItem item1 = new MenuItem("Insert poles");            
            menu.getItems().add(item1);
            item1.setOnAction(new EventHandler<ActionEvent>() {
                @Override
                public void handle(ActionEvent arg0) {              
                                getTreeItem().getChildren().add(item2);                               
                }
            });              
        }
        @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(menu);
                    }
                }           
            }
        }
        private String getString() {
            return getItem() == null ? "" : getItem().toString();
        }
    }  
}

With this user can add existing branch "poles". But the problem is, user cannot add Poles inside any pole branch.

[Application work like this user have to use existing branch "pole" as newly added branch and can add as many poles as he want inside any branch.]

Any good Idea will be helpful Please.

Thank you

Answer 1

根据需要，新添加的分支在添加时应具有自己的叶子。使用现有分支来解决这个问题是错误的。添加

时应使用新分支

 private static class AddMenuTreeCell extends TextFieldTreeCell<String> {
        private ContextMenu menu = new ContextMenu();
        private TextField textField;
       // private TreeItem<String> newBranch;
        public AddMenuTreeCell() {

            MenuItem renameItem1 = new MenuItem("Insert Unite");

            menu.getItems().add(renameItem1);
            renameItem1.setOnAction(new EventHandler<ActionEvent>() {

                @Override
                public void handle(ActionEvent arg0) {                      
                    TreeItem<String> item3 = new TreeItem<String>("poles");
                    item3.getChildren().addAll(new TreeItem<>("x"),new TreeItem<>("y"));
                            getTreeItem().getChildren().add(item3);                   
                }

            });

        }

JavaFx: Using existing branch as newly added branch

1 个答案: