java.awt.Robot keyPress 事件持续按下

Question

我正在尝试在 Java 中创建自己的虚拟键盘。我正在使用 Robot 的 keyPress() 事件将 KeyEvent 触发到文本字段。按键事件正在运行，但它继续打印我按下的键。这是我的代码，请检查我做错了什么？

创建键盘的代码

package virtualkeyboard;

import java.awt.AWTException;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Robot;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JTextField;

public class Keyboard extends JDialog {

    private static final long serialVersionUID = 1L;

    private JTextField txtField;

    public Keyboard(JTextField txt) {

        this.txtField = txt;
        setModalityType(ModalityType.APPLICATION_MODAL);
        setLayout(new GridLayout(3, 3));

        for (int i = 0; i <= 9; i++){
            createButton(Integer.toString(i));
        }

        pack();
    }

    private void createButton(String label) {
        JButton btn = new JButton(label);
        btn.setFocusPainted(false);
        btn.setPreferredSize(new Dimension(100, 100));
        Font font = btn.getFont();
        float size = font.getSize() + 15.0f;
        btn.setFont(font.deriveFont(size));

        btn.addMouseListener(new MouseAdapter() {

            @Override
            public void mouseReleased(MouseEvent e) {

                txtField.requestFocus();

                Robot robot;

                try {

                    robot = new Robot();

                    if(label.equals("0"))
                        robot.keyPress(KeyEvent.VK_0);
                    else if(label.equals("1"))
                        robot.keyPress(KeyEvent.VK_1);
                    else if(label.equals("2"))
                        robot.keyPress(KeyEvent.VK_2);
                    else if(label.equals("3"))
                        robot.keyPress(KeyEvent.VK_3);
                    else if(label.equals("4"))
                        robot.keyPress(KeyEvent.VK_4);
                    else if(label.equals("5"))
                        robot.keyPress(KeyEvent.VK_5);
                    else if(label.equals("6"))
                        robot.keyPress(KeyEvent.VK_6);
                    else if(label.equals("7"))
                        robot.keyPress(KeyEvent.VK_7);
                    else if(label.equals("8"))
                        robot.keyPress(KeyEvent.VK_8);
                    else if(label.equals("9"))
                        robot.keyPress(KeyEvent.VK_9);

                } catch (AWTException e1) {
                    e1.printStackTrace();
                }
            }
        });

        add(btn);
    }
}

Window 带有文本字段

package virtualkeyboard;

import java.awt.Dimension;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JDialog;
import javax.swing.JTextField;

public class WindowOne extends JDialog {

    private JTextField txtField = new JTextField();

    private Keyboard keyboard = new Keyboard(txtField);

    public WindowOne(){

        setSize(new Dimension(250,30));

        txtField.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                if(isEnabled()){
                    Point p = getLocationOnScreen();
                    p.y += 30;
                    keyboard.setLocation(p);
                    keyboard.setVisible(true);
                }
            }
        });

        add(txtField);

    }

    public static void main(String[] args) {
        new WindowOne().setVisible(true);
    }

}

编辑：

我对代码进行了以下更改，并在按下按钮时使 JTextfield 可聚焦。

private void createButton(String label,JTextField txt) {

        JButton btn = new JButton(label);
        btn.setFocusPainted(false);
        btn.setPreferredSize(new Dimension(100, 100));
        Font font = btn.getFont();
        float size = font.getSize() + 15.0f;
        btn.setFont(font.deriveFont(size));
        btn.setFocusable(false);

        btn.addMouseListener(new MouseAdapter() {

            @Override
            public void mouseClicked(MouseEvent e) {

                txt.getParent().requestFocus();
                txt.requestFocus();

                robot.delay(100);

                if(label.equals("0"))
                    robot.keyPress(KeyEvent.VK_0);
                else if(label.equals("1"))
                    robot.keyPress(KeyEvent.VK_1);
                else if(label.equals("2"))
                    robot.keyPress(KeyEvent.VK_2);
                else if(label.equals("3"))
                    robot.keyPress(KeyEvent.VK_3);
                else if(label.equals("4"))
                    robot.keyPress(KeyEvent.VK_4);
                else if(label.equals("5"))
                    robot.keyPress(KeyEvent.VK_5);
                else if(label.equals("6"))
                    robot.keyPress(KeyEvent.VK_6);
                else if(label.equals("7"))
                    robot.keyPress(KeyEvent.VK_7);
                else if(label.equals("8"))
                    robot.keyPress(KeyEvent.VK_8);
                else if(label.equals("9"))
                    robot.keyPress(KeyEvent.VK_9);

                requestFocusInWindow();
            }
        });
        add(btn);
    }

如果我按下按钮，它会继续在文本字段中打印数字。但是事件只触发一次。

请检查。

Answer 1

我找到了问题的解决方案，

对于每个 keyPress 事件，我们都需要触发相应的 keyRelease 事件，然后它才会停止 keyPress 事件，否则将被视为长按。

更改了这一行

if(keyCode.equals("VK_0")){
    robot.keyPress(KeyEvent.VK_0);
}

至

if(keyCode.equals("VK_0")){
    robot.keyPress(KeyEvent.VK_0);
    robot.keyRelease(KeyEvent.VK_0);
}

java.awt.Robot keyPress 事件持续按下

java.awt.Robot keyPress event is keep on pressing

java

swing

virtual-keyboard