为什么mouseClicked方法的 @Override下有红色波浪线
时间: 2024-04-18 12:27:28 浏览: 99
红色波浪线通常表示编译错误或警告。在使用`@Override`注解时,如果出现红色波浪线,可能是以下几种情况:
1. 方法签名不匹配:`@Override`注解用于标记覆盖父类中的方法,确保方法签名(名称、参数类型和返回类型)与父类中的方法一致。如果出现红色波浪线,可能是因为方法签名不匹配导致的。请确保方法名、参数列表和返回类型与父类中被覆盖的方法完全一致。
2. 继承关系错误:`@Override`注解要求被标记的方法必须是在父类或接口中已经存在的方法。如果父类或接口中没有对应的方法,那么就不能使用`@Override`注解。请检查你的类是否正确继承了父类或实现了接口,并且父类或接口中存在被覆盖的方法。
3. 编译器级别错误或警告:有时候,编译器可能会发出特定的错误或警告,导致出现红色波浪线。这可能是由于编译器版本、配置或其他因素引起的。在这种情况下,你可以尝试重新编译或更新编译器版本来解决问题。
请仔细检查以上可能的原因,并相应地调整代码以解决问题。如果仍然有疑问或问题,请提供更多的代码和错误信息,我将尽力帮助你解决。
相关问题
在ui设计器中from文件已经建好,我的代码如下,如何使用它import javax.swing.*; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; public class GRID extends JFrame { private JTabbedPane tabbedPane2; private JButton 结账Button; private JButton 取消订单Button; private JTable table1; private JTable table2; private JTable table3; private JTable table4; private JTable table5; private JTable table6; private JTable table7; private JTable table8; private JTextPane textPane1; public void GRID() { table2.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table1.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table3.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table4.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table5.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table6.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table7.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); table8.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { super.mouseClicked(e); } }); } public static void main(String[] args) { new GRID(); } }
你可以将这段代码保存为一个名为GRID.java的文件,然后在命令行中使用javac命令编译它,生成一个名为GRID.class的字节码文件。接着,你可以在其他Java类中使用import语句导入GRID类,然后创建它的实例来使用它的方法和属性。例如:
```
import javax.swing.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
public class MyOtherClass {
public static void main(String[] args) {
GRID grid = new GRID();
// 调用GRID实例的方法和属性
grid.table1.setModel(...);
grid.table2.addMouseListener(...);
// ...
}
}
```
public class JavaMain { public static void main(String[] args) { new MyWindow(); } } class MyWindow extends JFrame implements MouseListener, MouseMotionListener, ActionListener { //定义两个点 private Point oldPoint = null,newPoint = null; public MyWindow () { this.setSize(600,600); addMouseListener(this); addMouseMotionListener(this); this.setVisible(true); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } //画图 public void paint(Graphics g) { Graphics2D g2 = (Graphics2D) g; g2.setStroke(new BasicStroke(10.0f)); g2.setColor(Color.red); if(oldPoint!=null&&newPoint!=null) { g2.drawLine(oldPoint.x, oldPoint.y, newPoint.x, newPoint.y); oldPoint=newPoint; newPoint=null;//置为空,为了迎接下一个点的到来 } } //鼠标拖动事件 @Override public void mouseDragged(MouseEvent e) { if(oldPoint==null) { oldPoint=e.getPoint(); }else { newPoint=e.getPoint(); repaint();//生成新的点,通知系统去更新绘图 } } @Override public void mouseMoved(MouseEvent e) {} //鼠标单击事件 @Override public void mouseClicked(MouseEvent e) {} @Override public void mouseEntered(MouseEvent e) {} @Override public void mouseExited(MouseEvent e) {} @Override public void mousePressed(MouseEvent e) {} //鼠标释放事件,清空工作 @Override public void mouseReleased(MouseEvent e) { newPoint=null; oldPoint=null; } }设置清除画布按钮
您可以在 `MyWindow` 类中添加一个按钮,并为其添加一个 `ActionListener`,在按钮被点击时清除画布。代码示例如下:
```java
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class MyWindow extends JFrame implements MouseListener, MouseMotionListener, ActionListener {
private Point oldPoint = null, newPoint = null;
private JButton clearButton; // 添加一个清除按钮
public MyWindow() {
this.setSize(600, 600);
addMouseListener(this);
addMouseMotionListener(this);
// 初始化清除按钮
clearButton = new JButton("清除画布");
clearButton.addActionListener(this);
JPanel buttonPanel = new JPanel();
buttonPanel.add(clearButton);
add(buttonPanel, BorderLayout.SOUTH);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void paint(Graphics g) {
Graphics2D g2 = (Graphics2D) g;
g2.setStroke(new BasicStroke(10.0f));
g2.setColor(Color.red);
if (oldPoint != null && newPoint != null) {
g2.drawLine(oldPoint.x, oldPoint.y, newPoint.x, newPoint.y);
oldPoint = newPoint;
newPoint = null;
}
}
@Override
public void mouseDragged(MouseEvent e) {
if (oldPoint == null) {
oldPoint = e.getPoint();
} else {
newPoint = e.getPoint();
repaint();
}
}
@Override
public void mouseMoved(MouseEvent e) {}
@Override
public void mouseClicked(MouseEvent e) {}
@Override
public void mouseEntered(MouseEvent e) {}
@Override
public void mouseExited(MouseEvent e) {}
@Override
public void mousePressed(MouseEvent e) {}
@Override
public void mouseReleased(MouseEvent e) {
newPoint = null;
oldPoint = null;
}
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == clearButton) {
Graphics g = getGraphics();
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), getHeight());
}
}
}
```
在上面的代码中,我们添加了一个 `clearButton` 按钮,并在其上添加了一个 `ActionListener`。当按钮被点击时,会调用 `actionPerformed` 方法清除画布。在 `actionPerformed` 方法中,我们获取了 `MyWindow` 的 `Graphics` 对象,并使用 `fillRect` 方法覆盖整个画布。这样就达到了清除画布的效果。
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