Question

问题是垂直滚动条不会真正停止，而是先停止一个节点。如果您保持拆分视图打开，这可以正常工作。据我所知，这是因为Java本身存在以下问题。

如果垂直滚动条滚动到最大值，则JSplitPane的单触式可展开按钮会将垂直滚动条值减少15，然后单击单触式可展开按钮以最小化左窗格。

任何人都可以通过（使用附加的样本测试）验证这一点，看到GUI更改了滚动条的位置。使用控制台输出也可以验证相同。

在我看来这是一个错误，我已将此报告为Oracle中的一个错误 - Java。但尚未被接受。

任何解决方法？

import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreePath;

/**
 * Sample code.
 * 
 * @author Saurav.Kumar
 * 
 */
public class OneTouchBug {

    public void playUI() {
        DefaultMutableTreeNode root;
        root = new DefaultMutableTreeNode(0);
        final JTree tree = new JTree(root);
        JLabel bugLabel = new JLabel(
                "<html>One touch button will reduce the vScroll <br>" +
                "value by 15 if it is scrolled to maximum value and <br>" + 
                " then click one-touch Expandable ");
        JPanel p = new JPanel();
        p.add(bugLabel);
        final JScrollPane jScrollPane = new JScrollPane(tree, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
                JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
        final JSplitPane sptPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, jScrollPane, p);
        sptPane.setDividerLocation(90);
        sptPane.setOneTouchExpandable(true);
        jScrollPane.getVerticalScrollBar().addAdjustmentListener(new AdjustmentListener() {
            @Override
            public void adjustmentValueChanged(AdjustmentEvent e) {
                System.out.println("=======================" + e.getValue());
            }
        });
        JFrame f = new JFrame();
        f.getContentPane().add(sptPane);
        f.setSize(400, 200);
        f.setLocationRelativeTo(null);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setVisible(true);
        populateTree(root);
        tree.scrollPathToVisible(new TreePath(root.getLastLeaf().getPath()));
    }

    private void populateTree(DefaultMutableTreeNode root) {
        DefaultMutableTreeNode currentNode = root;
        int counter = 0;
        while (counter++ < 9) {
            DefaultMutableTreeNode nextNode = new DefaultMutableTreeNode("" + counter);
            currentNode.add(nextNode);
            currentNode = nextNode;
        }

    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new OneTouchBug().playUI();
            }
        });
    }
}

如果已经处于最大值，单击OneTouch按钮会将垂直滚动值减少15

0 个答案: