問題描述

In our application that has a JTabbedPane with unlimited tabs, when the width of the tabs exceeds the tabbed pane's width, the tabs start wrapping into several rows.然后，當您單擊上面一行中的一個選項卡時，整個行會下降到前臺.對于在多個選項卡之間單擊的用戶來說，這是非常令人困惑的，因為無法跟蹤選項卡順序.

In our application that has a JTabbedPane with unlimited tabs, when the width of the tabs exceeds the tabbed pane's width, the tabs start wrapping into several rows. When you then click on a tab in one of the upper rows, the complete row comes down and to the foreground. For users who click around between several tabs, it's highly confusing as it's not possible to keep track of the tab order.

我該怎么做- 將選項卡固定到固定位置，同時將它們的內容放在前面(盡管這會在視覺上破壞選項卡的隱喻，但我不在乎)，或者- 將行數限制為一(這樣標簽會變得非常窄而不是環繞)?

How can I either - nail the tabs to fixed positions while bringing their contents to the front (though this would optically corrupt the tab metaphor but I don't care), or - limit the number of rows to one (so the tabs get very narrow instead of wrapping)?

推薦答案

真的又快又臟(肯定需要改進和改變)，但我想這樣的東西可以為你工作(但不是 JTabbePane):

Really quick and dirty (definitely needs improvements and changes), but I would imagine that something like that could work for you (but is not a JTabbePane):

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;

import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;

public class Test {

    /**
     * FlowLayout subclass that fully supports wrapping of components.
     */
    public static class WrapLayout extends FlowLayout {
        private Dimension preferredLayoutSize;

        /**
         * Constructs a new <code>WrapLayout</code> with a left alignment and a
         * default 5-unit horizontal and vertical gap.
         */
        public WrapLayout() {
            super();
        }

        /**
         * Constructs a new <code>FlowLayout</code> with the specified alignment
         * and a default 5-unit horizontal and vertical gap. The value of the
         * alignment argument must be one of <code>WrapLayout</code>,
         * <code>WrapLayout</code>, or <code>WrapLayout</code>.
         * 
         * @param align
         *            the alignment value
         */
        public WrapLayout(int align) {
            super(align);
        }

        /**
         * Creates a new flow layout manager with the indicated alignment and
         * the indicated horizontal and vertical gaps.
         * <p>
         * The value of the alignment argument must be one of
         * <code>WrapLayout</code>, <code>WrapLayout</code>, or
         * <code>WrapLayout</code>.
         * 
         * @param align
         *            the alignment value
         * @param hgap
         *            the horizontal gap between components
         * @param vgap
         *            the vertical gap between components
         */
        public WrapLayout(int align, int hgap, int vgap) {
            super(align, hgap, vgap);
        }

        /**
         * Returns the preferred dimensions for this layout given the
         * <i>visible</i> components in the specified target container.
         * 
         * @param target
         *            the component which needs to be laid out
         * @return the preferred dimensions to lay out the subcomponents of the
         *         specified container
         */
        @Override
        public Dimension preferredLayoutSize(Container target) {
            return layoutSize(target, true);
        }

        /**
         * Returns the minimum dimensions needed to layout the <i>visible</i>
         * components contained in the specified target container.
         * 
         * @param target
         *            the component which needs to be laid out
         * @return the minimum dimensions to lay out the subcomponents of the
         *         specified container
         */
        @Override
        public Dimension minimumLayoutSize(Container target) {
            Dimension minimum = layoutSize(target, false);
            minimum.width -= getHgap() + 1;
            return minimum;
        }

        /**
         * Returns the minimum or preferred dimension needed to layout the
         * target container.
         * 
         * @param target
         *            target to get layout size for
         * @param preferred
         *            should preferred size be calculated
         * @return the dimension to layout the target container
         */
        private Dimension layoutSize(Container target, boolean preferred) {
            synchronized (target.getTreeLock()) {
                // Each row must fit with the width allocated to the containter.
                // When the container width = 0, the preferred width of the
                // container
                // has not yet been calculated so lets ask for the maximum.

                int targetWidth = target.getSize().width;

                if (targetWidth == 0) {
                    targetWidth = Integer.MAX_VALUE;
                }

                int hgap = getHgap();
                int vgap = getVgap();
                Insets insets = target.getInsets();
                int horizontalInsetsAndGap = insets.left + insets.right + hgap * 2;
                int maxWidth = targetWidth - horizontalInsetsAndGap;

                // Fit components into the allowed width

                Dimension dim = new Dimension(0, 0);
                int rowWidth = 0;
                int rowHeight = 0;

                int nmembers = target.getComponentCount();

                for (int i = 0; i < nmembers; i++) {
                    Component m = target.getComponent(i);

                    if (m.isVisible()) {
                        Dimension d = preferred ? m.getPreferredSize() : m.getMinimumSize();

                        // Can't add the component to current row. Start a new
                        // row.

                        if (rowWidth + d.width > maxWidth) {
                            addRow(dim, rowWidth, rowHeight);
                            rowWidth = 0;
                            rowHeight = 0;
                        }

                        // Add a horizontal gap for all components after the
                        // first

                        if (rowWidth != 0) {
                            rowWidth += hgap;
                        }

                        rowWidth += d.width;
                        rowHeight = Math.max(rowHeight, d.height);
                    }
                }

                addRow(dim, rowWidth, rowHeight);

                dim.width += horizontalInsetsAndGap;
                dim.height += insets.top + insets.bottom + vgap * 2;

                // When using a scroll pane or the DecoratedLookAndFeel we need
                // to
                // make sure the preferred size is less than the size of the
                // target containter so shrinking the container size works
                // correctly. Removing the horizontal gap is an easy way to do
                // this.

                Container scrollPane = SwingUtilities.getAncestorOfClass(JScrollPane.class, target);

                if (scrollPane != null) {
                    dim.width -= hgap + 1;
                }

                return dim;
            }
        }

        /*
         *  A new row has been completed. Use the dimensions of this row
         *  to update the preferred size for the container.
         *
         *  @param dim update the width and height when appropriate
         *  @param rowWidth the width of the row to add
         *  @param rowHeight the height of the row to add
         */
        private void addRow(Dimension dim, int rowWidth, int rowHeight) {
            dim.width = Math.max(dim.width, rowWidth);

            if (dim.height > 0) {
                dim.height += getVgap();
            }

            dim.height += rowHeight;
        }
    }

    public static class MyTabbedPane extends JPanel {
        private JPanel buttonPanel;
        private JPanel currentview;

        private Tab currentTab;

        private class Tab {
            String name;
            JComponent component;
        }

        private List<Tab> tabs = new ArrayList<Tab>();

        public MyTabbedPane() {
            super(new BorderLayout());
            buttonPanel = new JPanel(new WrapLayout());
            currentview = new JPanel();
            add(buttonPanel, BorderLayout.NORTH);
            add(currentview);
        }

        public void addTab(String name, JComponent tabView, int index) {
            if (index < 0 || index > tabs.size()) {
                throw new IllegalArgumentException("Index out of bounds");
            }
            final Tab tab = new Tab();
            tab.component = tabView;
            tab.name = name;
            tabs.add(index, tab);
            JButton b = new JButton(name);
            b.addActionListener(new ActionListener() {

                @Override
                public void actionPerformed(ActionEvent e) {
                    setCurrentTab(tab);
                }

            });
            buttonPanel.add(b, index);
            buttonPanel.validate();
        }

        public void removeTab(int i) {
            Tab tab = tabs.remove(i);

            if (tab == currentTab) {
                if (tabs.size() > 0) {
                    if (i < tabs.size()) {
                        setCurrentTab(tabs.get(i));
                    } else {
                        setCurrentTab(tabs.get(i - 1));
                    }
                } else {
                    setCurrentTab(null);
                }
            }
            buttonPanel.remove(index);
        }

        void setCurrentTab(final Tab tab) {
            if (currentTab == tab) {
                return;
            }
            if (currentTab != null) {
                currentview.remove(currentTab.component);
            }
            if (tab != null) {
                currentview.add(tab.component);
            }
            currentTab = tab;
            currentview.validate();
        }
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame();
        MyTabbedPane tabbedPane = new MyTabbedPane();
        for (int i = 0; i < 100; i++) {
            tabbedPane.addTab("Button " + (i + 1), new JLabel("Dummy Label " + (i + 1)), i);
        }
        frame.add(tabbedPane);
        frame.pack();
        frame.setSize(new Dimension(1000, 800));
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

}

WrapLayout 取自 SO 上的另一篇文章.

The WrapLayout was taken from another post on SO.

這篇關于JTabbedPane 或一行中固定位置的選項卡的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！