java如何在JTextfield中正确实现SHIFT+退格键笔划

Question

所以我有一个基本的swing应用程序，它包含一个JTextfield，我向它添加了以下KeyListener：

public class PromptKeyListener implements KeyListener {

    private boolean SHIFT_PRESSED;

    @Override
    public void keyPressed(KeyEvent e) {

        if (e.getKeyCode() == KeyEvent.VK_ENTER) {
            //Do Thing A
        } else if (e.getKeyCode() == KeyEvent.VK_SHIFT) {
            this.SHIFT_PRESSED = true;
        }

                     if (SHIFT_PRESSED
                && e.getKeyCode() == KeyEvent.VK_BACK_SPACE) {
            //Do Thing B
        }

       }

    @Override
    public void keyReleased(KeyEvent e) {

        if (e.getKeyCode() == KeyEvent.VK_SHIFT) {
            this.SHIFT_PRESSED = false;
        }
        System.out.println(SHIFT_PRESSED);
    }

    @Override
    public void keyTyped(KeyEvent e) {

    }

}

问题是，当我按住SHIFT键和Backspace键时，确实会出现Backspace键，但Backspace键也会像通常一样从文本框中删除单个字符

当按住SHIFT键时，是否有方法防止Backspace从文本框中删除字符

Answer 1

见Stopping default behavior of events in Swing

答案是你应该可以打电话

e.consume()

防止文本进入字段的默认行为

Answer 2

虽然解决方案有效，但您采取了错误的方法（IMHO）

您应该利用KeyBindingsAPI

InputMap im = field.getInputMap(JComponent.WHEN_FOCUSED);
ActionMap am = field.getActionMap();

im.put(KeyStroke.getKeyStroke(KeyEvent.VK_DELETE, KeyEvent.SHIFT_DOWN_MASK), "DoThingB");
am.put("DoThingB", new AbstractAction() {

    @Override
    public void actionPerformed(ActionEvent e) {

        System.out.println("Do Think B");

    }
});

此外，您不应该使用KeyListener来捕获enter键，您应该使用ActionListener