java - 从按钮/鼠标释放调用 Java AbstractAction

Question

在一个简单的计算器应用程序中，我使用抽象操作来处理用鼠标单击的按钮和按下的相应数字键盘键（带有键绑定）。我希望在使用键盘时发生某些外观变化，例如当我按下数字 1 键时更改 JButton 数字 1 的边框。并在发布时将其更改回来。这一切都有效。然后我又开始用鼠标按下 JButtons 并意识到释放键的动作永远不会被调用，显然是因为我没有使用键绑定。所以我的问题是，有没有办法在鼠标释放/按钮抬起时调用适当的释放抽象动作？

当我发现这一点时，我最初尝试了这个：

Abstract action(){
set border to this..
code..
code..
code..
set border to this..
}

所以无论是按键还是鼠标，它都会改变。但是它不会改变，或者可能会变得如此之快以至于无法检测到。

在这种情况下注册鼠标侦听器是没有意义的。无论如何我都试过了，我似乎无法将抽象动作注册为鼠标监听器。

感谢您的意见和想法。

我注册了actionlistener：

    btnMultiplication.addActionListener( operatorAction );
    btnDivision.addActionListener( operatorAction );
    btnAddition.addActionListener( operatorAction );
    btnSubtraction.addActionListener( operatorAction );
    btnSix.addActionListener( numberAction );
    btnSeven.addActionListener( numberAction );
    btnEight.addActionListener( numberAction );

*Action 是抽象动作

我用它来键盘输入

im.put( KeyStroke.getKeyStroke( KeyEvent.VK_NUMPAD0, 0, false ), "Number" );
im.put( KeyStroke.getKeyStroke( KeyEvent.VK_NUMPAD0, 0, true ), "Number Released" );
am.put( "Number", numberAction );
am.put( "Number Released", numberActionR );

我使用Number操作来更改相应 jbutton 的边框。然后我使用Number Released再次更改边框。

显然，当我用鼠标单击时，边框会突出显示。但是释放的数字不会调用。就像我说的那样，将释放的方面全部消除，并将第一个边界更改放在抽象动作的开始，然后在抽象动作结束时进行最后的边界更改，显然速度如此之快，以至于你看不到边界的变化。

score 3 · Accepted Answer

许多人在处理键绑定时会错过的一件事是，您可以注册“按下”或“释放”事件（默认为按下）。所以在你的情况下，你需要两者都做。“press”事件应该“arm”和“press”按钮，“release”应该“unpress”和“unarm”按钮（顺序很重要），例如......

我也会改变你的注意力。不要让键绑定触发所需的操作，而是JButton Action这样做，这将允许您专注于让键绑定更改按钮的状态，最好是通过使用按钮模型，这将允许按钮触发并关联Action调用。

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import static javax.swing.Action.NAME;
import javax.swing.ActionMap;
import javax.swing.InputMap;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            setLayout(new GridLayout(4, 3));
            add(createButton(7, KeyEvent.VK_7, KeyEvent.VK_NUMPAD7));
            add(createButton(8, KeyEvent.VK_8, KeyEvent.VK_NUMPAD8));
            add(createButton(9, KeyEvent.VK_9, KeyEvent.VK_NUMPAD9));
            add(createButton(4, KeyEvent.VK_4, KeyEvent.VK_NUMPAD4));
            add(createButton(5, KeyEvent.VK_5, KeyEvent.VK_NUMPAD5));
            add(createButton(6, KeyEvent.VK_6, KeyEvent.VK_NUMPAD6));
            add(createButton(1, KeyEvent.VK_1, KeyEvent.VK_NUMPAD1));
            add(createButton(2, KeyEvent.VK_2, KeyEvent.VK_NUMPAD2));
            add(createButton(3, KeyEvent.VK_3, KeyEvent.VK_NUMPAD3));
            add(createButton(0, KeyEvent.VK_0, KeyEvent.VK_NUMPAD0));
        }

        protected JButton createButton(int number, int... virtualKeys) {

            NumberAction na = new NumberAction(Integer.toString(number));
            JButton btn = new JButton(na);

            InputMap im = btn.getInputMap(WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
            ActionMap am = btn.getActionMap();

            for (int virtualKey : virtualKeys) {

                im.put(KeyStroke.getKeyStroke(virtualKey, 0, false), "number-pressed");
                im.put(KeyStroke.getKeyStroke(virtualKey, 0, true), "number-released");

            }

            am.put("number-pressed", new NumberKeyPressedAction(btn, true));
            am.put("number-released", new NumberKeyPressedAction(btn, false));

            return btn;

        }

        public class NumberAction extends AbstractAction {

            public NumberAction(String name) {
                super(name);
            }

            @Override
            public void actionPerformed(ActionEvent e) {
                System.out.println(getValue(NAME) + " was clicked");
            }

        }

        public class NumberKeyPressedAction extends AbstractAction {

            private final JButton btn;
            private final boolean pressed;

            public NumberKeyPressedAction(JButton btn, boolean pressed) {
                // You could just pass the button model, but this was easier...
                this.btn = btn;
                this.pressed = pressed;
            }

            @Override
            public void actionPerformed(ActionEvent e) {
                if (pressed) {
                    btn.getModel().setArmed(pressed);
                    btn.getModel().setPressed(pressed);
                } else {
                    btn.getModel().setPressed(pressed);
                    btn.getModel().setArmed(pressed);
                }
            }

        }

    }

}

score 0 · Accepted Answer

因此，我想根据MadProgrammer提供的所选解决方案发布我的有效实现。

我删除了 jbuttons 的显式创建。我现在像这样创建它们：

createButton( 3, 5, 1, 1, ".", "btnDecimal", KeyEvent.VK_DECIMAL );
    createButton( 1, 5, 1, 2, "0", "btnZero", KeyEvent.VK_0, KeyEvent.VK_NUMPAD0 );
    createButton( 1, 4, 1, 1, "1", "btnOne", KeyEvent.VK_1, KeyEvent.VK_NUMPAD1 );
    createButton( 2, 4, 1, 1, "2", "btnTwo", KeyEvent.VK_2, KeyEvent.VK_NUMPAD2 );
    createButton( 3, 4, 1, 1, "3", "btnThree", KeyEvent.VK_3, KeyEvent.VK_NUMPAD3 );
    createButton( 1, 3, 1, 1, "4", "btnFour", KeyEvent.VK_4, KeyEvent.VK_NUMPAD4 );
    createButton( 2, 3, 1, 1, "5", "btnFive", KeyEvent.VK_5, KeyEvent.VK_NUMPAD5 );
    createButton( 3, 3, 1, 1, "6", "btnSix", KeyEvent.VK_6, KeyEvent.VK_NUMPAD6 );
    createButton( 1, 2, 1, 1, "7", "btnSeven", KeyEvent.VK_7, KeyEvent.VK_NUMPAD7 );
    createButton( 2, 2, 1, 1, "8", "btnEight", KeyEvent.VK_8, KeyEvent.VK_NUMPAD8 );
    createButton( 3, 2, 1, 1, "9", "btnNine", KeyEvent.VK_9, KeyEvent.VK_NUMPAD9 );

createButton方法执行此操作：

private void createButton( int x, int y, int h, int w, String actionCommand, String name, int... keys ) {

    nAction na = new nAction( actionCommand );
    JButton btn = new JButton( na );
    btn.setName( name );
    InputMap im = btn.getInputMap( WHEN_IN_FOCUSED_WINDOW );
    ActionMap am = btn.getActionMap();

    for ( int virtualKey : keys ) {

        im.put( KeyStroke.getKeyStroke( virtualKey, 0, false ), "number-pressed" );
        im.put( KeyStroke.getKeyStroke( virtualKey, 0, true ), "number-released" );

    }

    am.put( "number-pressed", new NumberKeyPressedAction( btn, true ) );
    am.put( "number-released", new NumberKeyPressedAction( btn, false ) );

    GridBagConstraints gbc_btn = new GridBagConstraints();
    // gbc_btnEquals.anchor = GridBagConstraints.WEST;
    gbc_btn.fill = GridBagConstraints.BOTH;
    gbc_btn.insets = new Insets( 0, 0, 5, 5 );
    gbc_btn.gridheight = h;
    gbc_btn.gridwidth = w;
    gbc_btn.gridx = x;
    gbc_btn.gridy = y;
    frame.getContentPane().add( btn, gbc_btn );
    btn.setBackground( new Color( 225, 225, 225 ) );
    btn.setBorder( BorderFactory.createLineBorder( Color.BLACK ) );

如您所见，我创建了我的实例，正如 MadProgrammer 在他的示例中所示，并创建了对 AbstractActions 的引用。然后我设置各种挥杆属性的属性，然后设置边框和背景。这大大减少了代码和变量的使用。一个旁注。createButton中的参数名称及其用于命名按钮的用途不再使用，将被删除。

java - 从按钮/鼠标释放调用 Java AbstractAction

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