Question

我是java fx的新手。我正在使用treeview创建一个应用程序，并且通过嵌套集模型进行树视图。所以每个treeitem必须有左，右数据。（我做了一个像Treeitem＆gt;的树项目。对象有数据（id，标签名称，左，右等），String是要在treeview上显示的标签名称。）

问题是当我添加新的treeitem（或删除treeitem）时，必须更新整个treeitems。我已经实现了要在DB上更新的整个数据（其他treeitem），但是treeview仍然没有更新数据。

我找了刷新treeview的方法，但我发现用户不应该强行使用updateitem。

有没有办法或方法刷新整个树视图？

FYI。代码

Pair<LabelTreeItem,String> f = new Pair<>(new LabelTreeItem(1, "Root", 0, 0, "",0), "Root");

    try {
        f = new Pair<>(service.getRoot(), "Root");
    } catch (SQLException e) {
        System.out.println("Can't find Root Node");
        e.printStackTrace();
    }

    TreeItem<Pair<LabelTreeItem,String>> root = createNode(f);
    root.setExpanded(true);
    treeView.setRoot(root);
    treeView.setEditable(true);


    treeView.setCellFactory(new Callback<TreeView<Pair<LabelTreeItem,String>>,TreeCell<Pair<LabelTreeItem,String>>>(){
        @Override
        public TreeCell<Pair<LabelTreeItem,String>> call(TreeView<Pair<LabelTreeItem,String>> p) {              
            return new TextFieldTreeCellImpl();             
        }
    });

.....................................

private TreeItem<Pair<LabelTreeItem,String>> createNode(final Pair<LabelTreeItem,String> f) {
    return new TreeItem<Pair<LabelTreeItem,String>>(f) {
        private boolean isLeaf;
        private boolean isFirstTimeChildren = true;
        private boolean isFirstTimeLeaf = true;

        @Override public ObservableList<TreeItem<Pair<LabelTreeItem,String>>> getChildren() {
            if (isFirstTimeChildren) {
                isFirstTimeChildren = false;
                super.getChildren().setAll(buildChildren(this));
            }
            return super.getChildren();
        }

        @Override public boolean isLeaf() {
            if (isFirstTimeLeaf) {
                isFirstTimeLeaf = false;
                Pair<LabelTreeItem,String> f = getValue();

                int nodeLeft = f.getKey().getLeft();
                int nodeRight = f.getKey().getRight();

                if(nodeRight-nodeLeft == 1) {
                    isLeaf = true;
                    System.out.println("this is leaf");
                }
            }

            return isLeaf;
        }

        private ObservableList<TreeItem<Pair<LabelTreeItem,String>>> buildChildren(TreeItem<Pair<LabelTreeItem,String>> TreeItem) {
            Pair<LabelTreeItem,String> f = TreeItem.getValue();
            System.out.println("ID: "+f.getKey().getId());


            int nodeLeft = f.getKey().getLeft();
            int nodeRight = f.getKey().getRight();

            try {

                if (f != null && nodeRight-nodeLeft != 1) {
                    ArrayList<LabelTreeItem> item = new ArrayList<>();
                    item = service.getChildren(f.getKey().getLeft(), f.getKey().getRight(), f.getKey().getDepth());
                    ArrayList<Pair<LabelTreeItem,String>> itemList = new ArrayList<>();
                    for(int i=0; i<item.size(); i++) {
                        System.out.println("test : " + item.get(i).getLabel());

                        Pair<LabelTreeItem,String> pair = createPair(item.get(i), item.get(i).getLabel());
                        itemList.add(pair);
                    }

                    if(itemList.size() != 0) {
                        ObservableList<TreeItem<Pair<LabelTreeItem,String>>> children = FXCollections.observableArrayList();

                        for (Pair<LabelTreeItem,String> childNode : itemList) {
                            children.add(createNode(childNode));
                        }

                        return children;
                    }
                }
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return FXCollections.emptyObservableList();
        }
    };
}

private Pair<LabelTreeItem, String> createPair(LabelTreeItem item, String name) {
    return new Pair<>(item, name);
}

LabelTreeItem.java

public class LabelTreeItem {
private int id;
private String label;
private int left;
private int right;
private String comment;
private int depth;

public LabelTreeItem(int id, String label, int left, int right, String comment, int depth) {
    this.id = id;
    this.label = label;
    this.left = left;
    this.right = right;
    this.comment = comment;
    this.depth = depth;
}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getLabel() {
    return label;
}

public void setLabel(String label) {
    this.label = label;
}

public int getLeft() {
    return left;
}

public void setLeft(int left) {
    this.left = left;
}

public int getRight() {
    return right;
}

public void setRight(int right) {
    this.right = right;
}

public String getComment() {
    return comment;
}

public void setComment(String comment) {
    this.comment = comment;
}

public int getDepth() {
    return depth;
}

public void setDepth(int depth) {
    this.depth = depth;
}
}

TextFieldTreeCellImpl.java

public TextFieldTreeCellImpl() {
    service = SqliteService.getInstance();
    MenuItem addLabel = new MenuItem("Label add");
    addMenu.getItems().add(addLabel);
    addLabel.setOnAction(new EventHandler<ActionEvent>() {
        @Override
        public void handle(ActionEvent event) {
            getTreeItem().setExpanded(true);

            LabelTreeItem newItem = null;
            try {
                id = getTreeItem().getValue().getKey().getId();
                label = getTreeItem().getValue().getKey().getLabel();
                depth = getTreeItem().getValue().getKey().getDepth()+1;
                left = getTreeItem().getValue().getKey().getLeft();
                right = getTreeItem().getValue().getKey().getRight();

                newItem = service.getData("New Label", id,depth);
                TreeItem<Pair<LabelTreeItem,String>> newLabel = new TreeItem(createPair(newItem, newItem.getLabel()));
                getTreeItem().getChildren().add(newLabel);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    });

    MenuItem editLabel = new MenuItem("Label modify");
    addMenu.getItems().add(editLabel);
    editLabel.setOnAction(new EventHandler<ActionEvent>() {
        @Override
        public void handle(ActionEvent event) {
            startEdit();
        }
    });

    MenuItem removeLabel = new MenuItem("Label delete");
    addMenu.getItems().add(removeLabel);
    removeLabel.setOnAction(new EventHandler<ActionEvent>() {
        @Override
        public void handle(ActionEvent event) {
            try {
                left = getTreeItem().getValue().getKey().getLeft();
                right = getTreeItem().getValue().getKey().getRight();
                service.deleteData(left, right, (right-left)+1);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            getTreeItem().getParent().getChildren().remove(getTreeItem());

            System.out.println("Remove");
        }
    });
}

@Override 
protected void updateItem(final Pair<LabelTreeItem, String> pair, boolean empty) {
    super.updateItem(pair, empty);

    if (!empty && pair != null) {
        if (isEditing()) {
            if (textField != null) {
                textField.setText(getString());
            }
            setText(null);
            setGraphic(textField);
        } else {

            setText(pair.getKey().getLabel());
            setGraphic(getTreeItem().getGraphic());
            setContextMenu(addMenu);
        }
    } else {
        setText(null);
        setGraphic(null);
    }

    setOnMouseExited(new EventHandler<MouseEvent>() {

        @Override
        public void handle(MouseEvent event) {
            if(pair !=null){
                Tooltip tTip = new Tooltip(pair.getKey().getLabel());
                tTip.uninstall(getTreeView(), tTip);
            }
        }
    });

    setOnMouseEntered(new EventHandler<MouseEvent>() {

        @Override
        public void handle(MouseEvent event) {
            if(pair !=null){
                Tooltip tTip = new Tooltip();
                tTip.setText(pair.getKey().getLabel()
                        +"\nComment : "+pair.getKey().getComment()
                        +"\nLeft : "+pair.getKey().getLeft()
                        +"\nRight : "+pair.getKey().getRight());
                tTip.setFont(new Font("Arial", 16));
                tTip.setStyle("-fx-background-color: grey;");
                tTip.centerOnScreen();
                tTip.install(getTreeView(), tTip);

            }
        }
    });
}

数据库表

id|label|left|right|comment|depth

JavaFx - 有没有办法刷新整个树视图？

0 个答案: