java - 获取 SWT 树中的所有 TreeItems

Question

我想从我的 SWT 树中获取所有 TreeItem 的数组。但是，Tree 类中包含的方法 getItems() 仅返回树的第一层上的项目(即不是任何子项的项目)。

有人可以建议一种获取所有子项/项目的方法吗？

Answer 1

Tree#getItems() 的文档非常具体:

Returns a (possibly empty) array of items contained in the receiver that are direct item children of the receiver. These are the roots of the tree.

下面是一些可以解决问题的示例代码:

public static void main(String[] args)
{
    Display display = new Display();
    final Shell shell = new Shell(display);
    shell.setText("StackOverflow");
    shell.setLayout(new FillLayout());

    final Tree tree = new Tree(shell, SWT.MULTI);

    TreeItem parentOne = new TreeItem(tree, SWT.NONE);
    parentOne.setText("Parent 1");
    TreeItem parentTwo = new TreeItem(tree, SWT.NONE);
    parentTwo.setText("Parent 2");

    for (int i = 0; i < 10; i++)
    {
        TreeItem item = new TreeItem(parentOne, SWT.NONE);
        item.setText(parentOne.getText() + " child " + i);

        item = new TreeItem(parentTwo, SWT.NONE);
        item.setText(parentTwo.getText() + " child " + i);
    }

    parentOne.setExpanded(true);
    parentTwo.setExpanded(true);

    List<TreeItem> allItems = new ArrayList<TreeItem>();

    getAllItems(tree, allItems);

    System.out.println(allItems);

    shell.pack();
    shell.open();
    while (!shell.isDisposed())
    {
        if (!display.readAndDispatch())
            display.sleep();
    }
    display.dispose();
}

private static void getAllItems(Tree tree, List<TreeItem> allItems)
{
    for(TreeItem item : tree.getItems())
    {
        getAllItems(item, allItems);
    }
}

private static void getAllItems(TreeItem currentItem, List<TreeItem> allItems)
{
    TreeItem[] children = currentItem.getItems();

    for(int i = 0; i < children.length; i++)
    {
        allItems.add(children[i]);

        getAllItems(children[i], allItems);
    }
}