javafx如何禁用checkboxTreeItem中的一个项目？ [英] javafx how to disable one item in checkboxTreeItem?

问题描述

我是JavaFX的新手，我在复选框树视图中遇到问题。
我想在根值** 序列号中禁用一个项目，但根据JavaFX文档，似乎不可能。

I am new to JavaFX and I am having a problem in checkbox Tree View.
I want to disable one item inside root value **Serial No but as per JavaFX documentation, it seems that it is not possible.

我已禁用点击效果 cbTreeViewdisable（treeItems，3）

有没有办法让任何一个值变灰（或设置一个id），以便用户知道它被禁用。

I have disabled click effect cbTreeViewdisable(treeItems, 3)
Is there any way to grey out any one value (or set an id) so that user knows it is disabled.

private TreeView<String> cbTreeView;    
@Override
public void start(Stage primaryStage) {
 StackPane root = new StackPane();
 cbTreeView = new TreeView();
 CheckboxTreeItem<String> rootItem = new CheckboxTreeItem("Serial No.");
 final CheckboxTreeItem[] treeItems = new CheckboxTreeItem[6];
 for (int i = 0; i < 6; i++) {
   treeItems[i] = new CheckboxTreeItem(""+i+"");
   rootItem.getChildren().addAll(treeItems[i]);  
 }

 root.setExpanded(true);
 CheckboxTreeItem rootItem2 = new CheckboxTreeItem("child1");
 final CheckboxTreeItem[] treeItems2 = new CheckboxTreeItem[6];

 for (int i = 0; i < 6; i++) {
   treeItems2[i] = new CheckboxTreeItem(""+i+"");
   rootItem2.getChildren().addAll(treeItems2[i]);  
 }

 cbTreeView.setRoot(rootItem);
 cbTreeView.setCellFactory(CheckboxTreeCell.<String>forTreeView());
 rootItem.getChildren().set(2,rootItem2);
 cbTreeViewdisable(treeItems, 3);
 //rest of code imports css and draws stage which is not relevant to my question
 }

 private void cbTreeViewdisable(final CheckboxTreeItem[] treeItems, final int id) {
    treeItems[id].setIndependent(Boolean.TRUE);
    treeItems[id].setValue(treeItems[id].getValue().toString()+" Note: you can't select this!)");
    treeItems[id].selectedProperty().addListener(new ChangeListener<Boolean>() {

    @Override
    public void changed(ObservableValue<? extends Boolean> observable, 
        Boolean oldvalue, Boolean newvalue) {
        Platform.runLater(new Runnable() {
        @Override
        public void run() {
            treeItems[id].setSelected(Boolean.FALSE);       
   } 

推荐答案

一个允许禁用树的单个项目的方法是将它们的单元格禁用属性绑定到您可以在运行时修改的外部属性。为此，当我们设置单元格工厂时，我们可以将此绑定添加到单元格实现。但是我们需要一个引用，所以我们将使用项目的值，为了简单起见（这需要唯一的值）。

One way to allow disabling single items of the tree is binding their cell disable property to an external property you can modify on runtime. For that, when we set the cell factory, we can add this binding to the cell implementation. But we need a reference, so we'll use the value of the item, for the sake of simplicity (this requires unique values).

让我们使用这个pojo：

Let's use this pojo:

class Wrap {

    public Wrap(String name){
        this.name.set(name);
        this.disabled.set(false);
    }

    private final StringProperty name = new SimpleStringProperty();

    public String getName() {
        return name.get();
    }

    public void setName(String value) {
        name.set(value);
    }

    public StringProperty nameProperty() {
        return name;
    }
    private final BooleanProperty disabled = new SimpleBooleanProperty();

    public boolean isDisabled() {
        return disabled.get();
    }

    public void setDisabled(boolean value) {
        disabled.set(value);
    }

    public BooleanProperty disabledProperty() {
        return disabled;
    }
}

所以我们可以为所有项目设置一个集合在树视图上：

so we can have one collection for all of the items on the tree view:

private TreeView<String> cbTreeView; 
private final List<Wrap> disableList = new ArrayList<>();

@Override
public void start(Stage primaryStage) {
    cbTreeView = new TreeView();

    CheckBoxTreeItem<String> rootItem = new CheckBoxTreeItem("Serial No.");
    final List<CheckBoxTreeItem<String>> treeItems = new ArrayList<>(6);
    for (int i = 0; i < 6; i++) {
        CheckBoxTreeItem<String> item = new CheckBoxTreeItem("0"+i+"");
        item.setIndependent(true);
        treeItems.add(item);  
        disableList.add(new Wrap("0"+i+""));
    }
    rootItem.getChildren().addAll(treeItems);

    rootItem.setExpanded(true);
    rootItem.setIndependent(true);
    CheckBoxTreeItem<String> rootItem2 = new CheckBoxTreeItem("child1");
    final List<CheckBoxTreeItem<String>> treeItems2 = new ArrayList<>(6);
    for (int i = 0; i < 6; i++) {
        CheckBoxTreeItem<String> item = new CheckBoxTreeItem("1"+i+"");
        item.setIndependent(true);
        treeItems2.add(item); 
        disableList.add(new Wrap("1"+i+""));
    }
    rootItem2.getChildren().addAll(treeItems2);
    rootItem2.setIndependent(true);
    rootItem.getChildren().set(2,rootItem2);

    cbTreeView.setRoot(rootItem);

现在我们创建单元工厂，并在设置项目的值时提供绑定：

Now we create the cell factory, and provide the binding, when the value of the item is set:

    cbTreeView.setCellFactory((TreeView<String> item) -> {

        final CheckBoxTreeCell<String> cell = new CheckBoxTreeCell<>();

        cell.itemProperty().addListener((obs,s,s1)->{
            cell.disableProperty().unbind();
            if(s1!=null && !s1.isEmpty()){
                Wrap wrap=disableList.stream()
                        .filter(w->w.getName().equals(s1))
                        .findFirst().orElse(null);
                if(wrap!=null){
                    cell.disableProperty().bind(wrap.disabledProperty());
                }
            }
        });
        return cell;
    });

最后，我们展示舞台，并禁用一些随机项：

And finally, we show the stage, and disable some random items:

    Scene scene=new Scene(cbTreeView);
    primaryStage.setScene(scene);
    primaryStage.show();

    // disable by name
    disableList.stream()
            .filter(w->w.getName().equals("03"))
            .findFirst().ifPresent(w->w.setDisabled(true));
    // disable by order
    disableList.get(7).setDisabled(true);

}

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