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我为我的应用程序制作了一个 gui。JFrame 有 2 个 JPanel,panel1 和 panel2。panel1 就是这样,一个带有自定义绘画的 JPanel,每 5 毫秒重新绘画一次。

panel2 是我第一次尝试 CardLayout 实现:它包含 JPanels subPanel1 和 subPanel2。subPanel1 包含一个 JComboBox 并添加到 panel2: panel2.add(subPanel1);

subPanel2 有.setLayout(new CardLayout());命令,我在其中添加了 3 个新的 JPanel,以及适当的 itemListener 和所有。当然我也加了:panel2.add(subPanel2);

现在来解决问题:关注 Java 中的组件。我有方法setFocusable(boolean)和知识requestFocus()。但我不能让他们以任何合乎逻辑的方式行事。

首先,它们的根本问题:当组合框获得焦点时,我根本无法取消焦点(尝试用光标单击任何地方)。

以下是我进行的实验:

1)在整个应用程序中没有任何代码说明焦点,组合框从焦点开始,无论面板1和面板2添加到JFrame中的哪个顺序。

2)如果我设置panel1.setFocusable(true);(在它的构造函数中)它将从焦点开始

3)如果我设置panel1.setFocusable(false);并请求关注它,它不会得到它。(只有按预期工作的东西)

4) 如果我将 panel2、subPanel1 或 subPanel2 单独或任意组合设置为不可聚焦,它们仍然可以接收焦点(组合框,即唯一能够注册焦点的组件)。

5)如果我将组合框设置为不可聚焦,我仍然可以使用框的 itemListener 在 CardLayout 中的卡片之间滚动,但焦点不会粘在它上面。事实上 panel1 仍然注册键盘输入

所以我真的对整个“专注”的事情感到非常困惑。也许这不是我认为的那样?我想要做的是完全阻止与 panel2 的所有交互,直到一个标志(每 5 毫秒评估一次)为真。我是否正确地假设与 JPanel 不同,JComboBox 在单击时自动具有 mousebuttonListener 以获得焦点?如果不是,那么如何完全禁用 JComboBox 和当前卡片显示的所有组件?不可聚焦组件中的组件仍然可聚焦是正常行为吗?

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2 回答 2

4

我尝试了许多不同的方法来解决类似的问题。

遍历组件层次结构并禁用每个组件的问题是您破坏了任何上下文并规避了对这些组件的管理。

基本上,如果在重新启用容器时某些子组件需要保持禁用状态,那么您会突然陷入多重责任交织的问题......

迄今为止我发现的最佳解决方案是简单地使用JXLayer,它提供了一个“可锁定”层概念,它允许您“锁定”单个容器,防止用户与之交互,例如......

在此处输入图像描述

这直接取自JXLayer演示代码...

/**
 * Copyright (c) 2006-2008, Alexander Potochkin
 * All rights reserved.
 */

package org.jdesktop.jxlayer.demo;

import com.jhlabs.image.BlurFilter;
import com.jhlabs.image.EmbossFilter;
import org.jdesktop.jxlayer.JXLayer;
import org.jdesktop.jxlayer.demo.util.LafMenu;
import org.jdesktop.jxlayer.plaf.effect.BufferedImageOpEffect;
import org.jdesktop.jxlayer.plaf.effect.LayerEffect;
import org.jdesktop.jxlayer.plaf.ext.LockableUI;
import org.jdesktop.swingx.painter.BusyPainter;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.Ellipse2D;

/**
 * A demo to show the abilities of the {@link LockableUI}.
 * 
 * @see BusyPainterUI  
 */
public class LockableDemo extends JFrame {
    private JXLayer<JComponent> layer;
    private LockableUI blurUI = 
            new LockableUI(new BufferedImageOpEffect(new BlurFilter()));
    private EnhancedLockableUI embossUI = 
            new EnhancedLockableUI(new BufferedImageOpEffect(new EmbossFilter()));
    private LockableUI busyPainterUI = new BusyPainterUI();

    private JCheckBoxMenuItem disablingItem =
            new JCheckBoxMenuItem(new AbstractAction("Lock the layer") {

                public void actionPerformed(ActionEvent e) {
                    blurItem.setEnabled(!disablingItem.isSelected());
                    embossItem.setEnabled(!disablingItem.isSelected());
                    busyPainterItem.setEnabled(!disablingItem.isSelected());

                    blurUI.setLocked(disablingItem.isSelected());
                    embossUI.setLocked(disablingItem.isSelected());
                    busyPainterUI.setLocked(disablingItem.isSelected());
                }
            });

    private JRadioButtonMenuItem blurItem = new JRadioButtonMenuItem("Blur effect");
    private JRadioButtonMenuItem embossItem = new JRadioButtonMenuItem("Unlock button");
    private JRadioButtonMenuItem busyPainterItem = new JRadioButtonMenuItem("BusyPainter");

    public LockableDemo() {
        super("Lockable layer demo");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JComponent view = createLayerPanel();
        layer = new JXLayer<JComponent>(view);

        layer.setUI(blurUI);
        add(layer);
        add(createToolPanel(), BorderLayout.EAST);
        setJMenuBar(createMenuBar());
        setSize(380, 300);
        setLocationRelativeTo(null);
    }

    public static void main(String[] args) throws Exception {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new LockableDemo().setVisible(true);
            }
        });
    }

    private JMenuBar createMenuBar() {
        JMenu menu = new JMenu("Menu");

        disablingItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_D, InputEvent.ALT_MASK));

        menu.add(disablingItem);
        menu.addSeparator();

        blurItem.setSelected(true);
        blurItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_1, InputEvent.ALT_MASK));
        menu.add(blurItem);

        embossItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_2, InputEvent.ALT_MASK));
        menu.add(embossItem);

        busyPainterItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_3, InputEvent.ALT_MASK));
        menu.add(busyPainterItem);

        ButtonGroup group = new ButtonGroup();
        group.add(blurItem);
        group.add(embossItem);
        group.add(busyPainterItem);

        ItemListener menuListener = new ItemListener() {
            public void itemStateChanged(ItemEvent e) {
                if (blurItem.isSelected()) {
                    layer.setUI(blurUI);
                } else if (embossItem.isSelected()) {
                    layer.setUI(embossUI);
                } else if (busyPainterItem.isSelected()) {
                    layer.setUI(busyPainterUI);
                }
            }
        };

        blurItem.addItemListener(menuListener);
        embossItem.addItemListener(menuListener);
        busyPainterItem.addItemListener(menuListener);

        embossUI.getUnlockButton().addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                disablingItem.doClick();
            }
        });

        JMenuBar bar = new JMenuBar();
        bar.add(menu);

        bar.add(new LafMenu());
        return bar;
    }

    private JComponent createLayerPanel() {
        JComponent panel = new JPanel();
        panel.add(new JCheckBox("JCheckBox"));
        panel.add(new JRadioButton("JRadioButton"));
        panel.add(new JTextField(15));
        JButton button = new JButton("Have a nice day");
        button.setMnemonic('H');
        button.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(LockableDemo.this,
                        "actionPerformed");
            }
        });
        panel.add(button);
        panel.add(new JTextField(15));
        panel.add(new JCheckBox("JCheckBox"));
        panel.add(new JRadioButton("JRadioButton"));
        panel.add(new JTextField(15));
        panel.add(new JCheckBox("JCheckBox"));
        panel.add(new JRadioButton("JRadioButton"));
        panel.setBorder(BorderFactory.createEtchedBorder());
        return panel;
    }

    private JComponent createToolPanel() {
        JComponent box = Box.createVerticalBox();
        JCheckBox button = new JCheckBox(disablingItem.getText());
        button.setModel(disablingItem.getModel());
        box.add(Box.createGlue());
        box.add(button);
        box.add(Box.createGlue());
        JRadioButton blur = new JRadioButton(blurItem.getText());
        blur.setModel(blurItem.getModel());
        box.add(blur);
        JRadioButton emboss = new JRadioButton(embossItem.getText());
        emboss.setModel(embossItem.getModel());
        box.add(emboss);
        JRadioButton translucent = new JRadioButton(busyPainterItem.getText());
        translucent.setModel(busyPainterItem.getModel());
        box.add(translucent);
        box.add(Box.createGlue());
        return box;
    }


    /**
     * Subclass of the {@link LockableUI} which shows a button
     * that allows to unlock the {@link JXLayer} when it is locked  
     */
    public static class EnhancedLockableUI extends LockableUI {
        private JButton unlockButton = new JButton("Unlock");

        public EnhancedLockableUI(LayerEffect... lockedEffects) {
            super(lockedEffects);
            unlockButton.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    setLocked(false);
                }
            });
            unlockButton.setVisible(false);
        }

        public AbstractButton getUnlockButton() {
            return unlockButton;
        }

        @Override
        @SuppressWarnings("unchecked")
        public void installUI(JComponent c) {
            super.installUI(c);
            JXLayer<JComponent> l = (JXLayer<JComponent>) c;
            l.getGlassPane().setLayout(new GridBagLayout());
            l.getGlassPane().add(unlockButton);
            unlockButton.setCursor(Cursor.getDefaultCursor());
        }

        @Override
        @SuppressWarnings("unchecked")
        public void uninstallUI(JComponent c) {
            super.uninstallUI(c);
            JXLayer<JComponent> l = (JXLayer<JComponent>) c;
            l.getGlassPane().setLayout(new FlowLayout());
            l.getGlassPane().remove(unlockButton);
        }

        public void setLocked(boolean isLocked) {
            super.setLocked(isLocked);
            unlockButton.setVisible(isLocked);
        }
    }

    /**
     * Subclass of the {@link LockableUI} which uses the {@link BusyPainterUI}
     * from the SwingX project to implement the "busy effect" 
     * when {@link JXLayer} is locked.  
     */
    public static class BusyPainterUI extends LockableUI 
            implements ActionListener {
        private BusyPainter busyPainter;
        private Timer timer;
        private int frameNumber;

        public BusyPainterUI() {
            busyPainter = new BusyPainter() {
                protected void doPaint(Graphics2D g, JComponent object,
                                       int width, int height) {
                    // centralize the effect
                    Rectangle r = getTrajectory().getBounds();
                    int tw = width - r.width - 2 * r.x;
                    int th = height - r.height - 2 * r.y;
                    g.translate(tw / 2, th / 2);
                    super.doPaint(g, object, width, height);
                }
            };
            busyPainter.setPointShape(new Ellipse2D.Double(0, 0, 20, 20));
            busyPainter.setTrajectory(new Ellipse2D.Double(0, 0, 100, 100));
            timer = new Timer(100, this);
        }

        @Override
        protected void paintLayer(Graphics2D g2, JXLayer<? extends JComponent> l) {
            super.paintLayer(g2, l);
            if (isLocked()) {
                busyPainter.paint(g2, l, l.getWidth(), l.getHeight());
            }
        }

        @Override
        public void setLocked(boolean isLocked) {
            super.setLocked(isLocked);
            if (isLocked) {
                timer.start();
            } else {
                timer.stop();
            }
        }

        // Change the frame for the busyPainter
        // and mark BusyPainterUI as dirty 
        public void actionPerformed(ActionEvent e) {
            frameNumber = (frameNumber + 1) % 8;
            busyPainter.setFrame(frameNumber);
            // this will repaint the layer
            setDirty(true);
        }
    }
}
于 2013-11-05T23:16:13.560 回答
2

听起来你真正想要使用的是.setEnabled(false)

如果您需要将面板中的所有组件设置为禁用,那么您可以使用这样的方法来执行此操作:(可能不是最好的方法,JComponents但可以根据需要轻松修改,但这确实有效)

public static void setContainerAndChildrenEnabled(Container c, boolean b)
{
    Component[] allComps = c.getComponents();
    for(Component com : allComps)
    {
        com.setEnabled(b);
        if(com instanceof Container)
            setContainerAndChildrenEnabled((Container) com, b);
    }
}

然后使用您要设置的面板和 true 或 false 调用它以启用/禁用。这也将递归地调用setEnabled()每个ComponentContainer

从文档中需要注意两点:

  1. 注意:禁用轻量级组件不会阻止它接收 MouseEvents。

  2. 注意:禁用重量级容器会阻止该容器中的所有组件接收任何输入事件。但是禁用轻量级容器只会影响这个容器。

isLightweight()

于 2013-11-05T22:24:04.250 回答