如何使上下文菜單在javaFX中的樹視圖上工作？

Question

我想在TreeView項目上有一個上下文菜單。 我期待事件處理程序的ActionEvent爲我提供有關哪個TreeView項目被點擊的信息，但我只是發現getSource和getTarget返回一個菜單項。我怎樣才能找出哪個TreeView項目被點擊？我可以在單獨的選項卡中有多個treevIews。

FileContextMenu cm = new FileContextMenu(new EventHandler<ActionEvent>() { 
     public void handle(ActionEvent e) { 
      System.out.println("Open File"); 
      //MenuItem mi = (MenuItem)e.getSource(); 
      EventTarget et = e.getTarget(); 
      //File editorFile = new File(mi.getId()); 
      System.out.println(et); 
      //mainWindowController.openEditor(editorFile); 
     } 
    }, new EventHandler<ActionEvent>() { 
     public void handle(ActionEvent e) { 
      System.out.println("Create Project From Template"); 
     } 
    }); 

調用該：

public class FileContextMenu extends ContextMenu 
    { 

      public FileContextMenu(EventHandler<ActionEvent> ehOpenFile, 

EventHandler<ActionEvent> ehProjectFromTemplate) 
     { 
      MenuItem item1 = new MenuItem("Open File"); 
      item1.setOnAction(ehOpenFile); 
      MenuItem item2 = new MenuItem("Create Project From Template"); 
      item2.setOnAction(ehProjectFromTemplate); 
      this.getItems().addAll(item1, item2);  
     } 
    } 

我附上這裏的菜單：

private void addFilesTab(FXMLLoader loader, String sRoot, ContextMenu cm) throws IOException 
{ 
    AnchorPane fileView = loader.load(); 
    FileViewController fileViewController = loader.getController(); 

    FileShort fsRoot = new FileShort(sRoot); 
    if(fsRoot.exists()) { 
     fileViewController.setRootFolder(fsRoot); 
     fileViewController.setContextMenu(cm); 
     ObservableList<Tab> tabs = navigationTabPane.getTabs(); 
     tabs.add(new Tab(sRoot)); 
     // Connect the FileView with last tab of the Navigation TabPane. 
     tabs.get(tabs.size()-1).setContent(fileView); 
    } 
} 

調用該：

public void setContextMenu(ContextMenu cm) 
{ 
    fileTreeView.setContextMenu(cm); 
} 

我現在嘗試使用cellfactory ，但我不明白如何使用p參數找到一個單元格值。我對這個代碼是：

this.fileTreeView.setCellFactory(new Callback<TreeView<FileShort>,TreeCell<FileShort>>(){ 
    @Override 
    public TreeCell<FileShort> call(TreeView<FileShort> p) { 
     TreeCell<FileShort> cell = new TreeCell<FileShort>(); 
     cell.setContextMenu(cm); 
     return cell; 
    } 
}); 

Answer 1

你必須創建每個小區的不同的上下文菜單：

this.fileTreeView.setCellFactory(new Callback<TreeView<FileShort>,TreeCell<FileShort>>(){ 
    @Override 
    public TreeCell<FileShort> call(TreeView<FileShort> p) { 
     TreeCell<FileShort> cell = new TreeCell<FileShort>() { 
      @Override 
      protected void updateItem(FileShort file, boolean empty) { 
       super.updateItem(file, empty); 
       if (empty) { 
        setText(null); 
       } else { 
        // maybe use a more appropriate string for display here 
        // e.g. if you were using a regular java.io.File you would 
        // likely want file.getName() 
        setText(file.toString()); 
       } 
      } 
     }; 
     ContextMenu cm = createContextMenu(cell); 
     cell.setContextMenu(cm); 
     return cell; 
    } 
}); 

private ContextMenu createContextMenu(TreeCell<FileShort> cell) { 
    ContextMenu cm = new ContextMenu(); 
    MenuItem openItem = new MenuItem("Open File"); 
    openItem.setOnAction(event -> { 
     FileShort file = cell.getItem(); 
     if (file != null) { 
      // open the file... 
     } 
    }); 
    cm.getItems().add(openItem); 
    // other menu items... 
    return cm ; 
}