java - SWT/JFace TreeColumn 重新排序 - setMoveable() 问题

Question

我正在尝试设置一个多列的 SWT Tree(通过 JFace TreeViewer)，它允许用户通过拖动列标题。但是，第一列应保持固定且不可移动。我可以在每个 TreeColumn 上使用 setMoveable(true) 方法，但第一个真正接近的除外，但这不会阻止用户将不同的列拖动到它。有什么解决办法吗？

这是一个简化的工作片段(没有 JFace)来说明问题:

import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.RowData;
import org.eclipse.swt.layout.RowLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeColumn;
import org.eclipse.swt.widgets.TreeItem;

public class TreeTableColumnMove {

    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setLayout(new RowLayout(SWT.HORIZONTAL));
        Tree tree = new Tree(shell, SWT.BORDER | SWT.CHECK);
        tree.setLayoutData(new RowData(-1, 100));
        tree.setHeaderVisible(true);
        for (int i = 0; i < 5; i++) {
            TreeColumn column = new TreeColumn(tree, SWT.CENTER);
            column.setText("Col " + i);
            column.setWidth(60);
            if (i > 0) column.setMoveable(true);
        }
        TreeItem item = new TreeItem(tree, SWT.NONE);
        item.setText(new String[] { "c0", "c1", "c2", "c3", "c4" });
        shell.pack();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}

Answer 1

这是我基于 danmec 的回答的最终解决方案:

import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.RowData;
import org.eclipse.swt.layout.RowLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeColumn;
import org.eclipse.swt.widgets.TreeItem;

    public class TreeTableColumnMove {

        public static void main(String[] args) {
            Display display = new Display();
            Shell shell = new Shell(display);
            shell.setLayout(new RowLayout(SWT.HORIZONTAL));
            final Tree tree = new Tree(shell, SWT.BORDER | SWT.CHECK);
            tree.setLayoutData(new RowData(-1, 100));
            tree.setHeaderVisible(true);
            Listener moveListener = new Listener() {
                public void handleEvent(Event e) {
                    int[] order = tree.getColumnOrder();
                    for(int i=0, col=0; i<order.length; i++) {
                        int tmp = order[i];
                        order[i] = col;
                        col = tmp;
                        if(col == 0)
                            if(i == 0) return;
                            else break;
                    }
                    tree.setColumnOrder(order);
                }
            };

            for (int i = 0; i < 5; i++) {
                TreeColumn column = new TreeColumn(tree, SWT.CENTER);
                column.setText("Col " + i);
                column.setWidth(60);
                if (i == 0)                 
                    column.addListener(SWT.Move, moveListener);
                else
                    column.setMoveable(true);
            }
            TreeItem item = new TreeItem(tree, SWT.NONE);
            item.setText(new String[] { "c0", "c1", "c2", "c3", "c4" });
            shell.pack();
            shell.open();
            while (!shell.isDisposed()) {
                if (!display.readAndDispatch())
                    display.sleep();
            }
            display.dispose();
        }
    }