首先,我作为网站程序员来到Java.在JavaScript中,您只需调用addEventListener函数即可添加mousemove,mouseover或click事件.根据我对Java的有限经验,您不能只从任何对象实现MouseListener接口.

基本上,到目前为止我所拥有的是一个JPanel,它绘制了一些具有x / y / width / height值的形状(带有绘制方法的CustomShape对象).我想在形状对象中添加一些类型的鼠标监听器,这样我就可以触发形状的移动/滚动/点击事件.只是将CustomLhaner接口实现到CustomShape对象不起作用(我认为这是显而易见的原因).我已经查找了如何设计自定义事件监听器,但似乎并不是可以创建自定义鼠标监听器.

我最终使用鼠标监听器添加到JPanel,然后循环遍历所有形状对象.如果形状对象附加了“侦听器”,并且鼠标坐标已验证鼠标事件已发生,则会触发该方法.最初,它很好,但随着应用程序越来越发达,它开始变得非常混乱.另外,如果不复制一堆代码,我将永远无法将形状对象/接口复制到另一个应用程序.

作为一个简单的说明:(实际代码非常大)

Interface CustomShape{

int width, height, x, y;

void paint(Graphics g);

}

public class StarShape implements CustomShape{

int width, height, x, y;

public StarShape(){

width = 100;

height = 100;

x = 50;

y = 50;

}

void paint(Graphics g){

g.setColor(Color.black);

g.draw(new Rectangle(x,y,width,height));

}

}

public class Main extends JPanel{

StarShape check = new StarShape();

public Main(){ }

@Override

public void paintComponent(Graphics g){

super.paintComponent(g);

check.paint(g);

}

}

所以,我想知道是否有一种干净的方式来实现某种类型的鼠标监听器的“手绘”形状.

解决方法:

我做你想做的事情的方法.编译,运行,阅读:-)

(注意：您可以将下面的每一行代码复制到单个文件Example01.java中.编译并运行它.)

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class Example01 {

public static void main(String[] args) {

SwingUtilities.invokeLater(new Runnable() {

public void run() {

JFrame jf = new JFrame();

MainPanel mainPanel = new MainPanel();

jf.add(mainPanel);

jf.setSize(640, 480);

jf.setLocationRelativeTo(null);

jf.setVisible(true);

}

});

}

}

class MainPanel extends JPanel {

StarShape check1 = new StarShape();

StarShape check2 = new StarShape();

public MainPanel() {

check1.setName("check1");

check2.setName("check2");

check1.addMouseListener(new MyMouseListener(check1));

check2.addMouseListener(new MyMouseListener(check2));

this.add(check1);

this.add(check2);

}

}

class StarShape extends JComponent {

public StarShape() {

this.setPreferredSize(new Dimension(100, 100));

}

@Override

protected void paintComponent(Graphics g) {

g.setColor(Color.black);

Graphics2D g2d = (Graphics2D) g;

int x = 0;

int y = 0;

int width = this.getWidth() - 1;

int height = this.getHeight() - 1;

g2d.draw(new Rectangle(x, y, width, height));

}

}

class MyMouseListener implements MouseListener {

private final JComponent component;

public MyMouseListener(JComponent component) {

this.component = component;

}

public void mouseClicked(MouseEvent e) {

System.out.println("mouseClicked: " + component.getName());

}

public void mouseEntered(MouseEvent e) {

System.out.println("mouseEntered: " + component.getName());

Dimension preferredSize = component.getPreferredSize();

preferredSize.height += 20;

preferredSize.width += 20;

component.setPreferredSize(preferredSize);

component.invalidate();

SwingUtilities.getWindowAncestor(component).validate();

}

public void mouseExited(MouseEvent e) {

System.out.println("mouseExited: " + component.getName());

Dimension preferredSize = component.getPreferredSize();

preferredSize.height -= 20;

preferredSize.width -= 20;

component.setPreferredSize(preferredSize);

component.invalidate();

SwingUtilities.getWindowAncestor(component).validate();

}

public void mousePressed(MouseEvent e) {

System.out.println("mousePressed: " + component.getName());

}

public void mouseReleased(MouseEvent e) {

System.out.println("mouseReleased: " + component.getName());

}

}

标签：java,swing,mouse-listeners

来源： https://codeday.me/bug/20190610/1212371.html