Java JPanel 上的 mouseListener 不工作
Java mouseListener on JPanel doesn't work
它是这样的:我想添加一个鼠标侦听器(鼠标进入、鼠标离开、鼠标单击)在自定义启动画面上.到目前为止我有了基本的想法,但我不知道如何让鼠标监听器工作。
如何在只有一个组件重写 paintComponent 方法的 JFrame 上添加 mouseListenner?
我试过了,我确定我做错了什么,但我找不到它是什么,我已经尝试了我能想到的所有方法。这是简单的程序(SSCCE):
package GUI.other;
public class SplashScreen2 {
private static final String IMAGE_LOCATION = new File(".").getAbsolutePath() + "/res/splashScreen.png";
public SplashScreen2() {
JFrame frame = new JFrame();
frame.getContentPane().add(new ImagePanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setUndecorated(true);
//The following doesnt work
frame.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
System.out.println("Pressed");
}
@Override
public void mouseReleased(MouseEvent e) {
System.out.println("Pressed");
}
});
frame.pack();
frame.setLocationRelativeTo(null);
frame.setBackground(new Color(0, 0, 0, 0));
frame.setVisible(true);
try {
Thread.sleep(5000);
frame.dispose();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new SplashScreen2();
}
});
}
@SuppressWarnings("serial")
public class ImagePanel extends JPanel {
BufferedImage img;
public ImagePanel() {
setOpaque(false);
setLayout(new GridBagLayout());
try {
img = ImageIO.read(new File(IMAGE_LOCATION));
} catch (IOException ex) {
ex.printStackTrace();
}
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(img, 0, 0, getWidth(), getHeight(), this);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(1080 / 2, 720 / 2);
}
}
}
结果如下:
您应该将侦听器添加到您的 ImagePanel
ImagePanel panel = new ImagePanel();
panel.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
System.out.println("Pressed");
}
@Override
public void mouseReleased(MouseEvent e) {
System.out.println("Pressed");
}
});
frame.add(panel);
此外,Thread.sleep(5000);
不起作用,因为您这样做了:
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new SplashScreen2();
}
});
您在事件调度线程上调用了构造函数,当您阻塞它时,将不会调度鼠标事件。
它是这样的:我想添加一个鼠标侦听器(鼠标进入、鼠标离开、鼠标单击)在自定义启动画面上.到目前为止我有了基本的想法,但我不知道如何让鼠标监听器工作。
如何在只有一个组件重写 paintComponent 方法的 JFrame 上添加 mouseListenner?
我试过了,我确定我做错了什么,但我找不到它是什么,我已经尝试了我能想到的所有方法。这是简单的程序(SSCCE):
package GUI.other;
public class SplashScreen2 {
private static final String IMAGE_LOCATION = new File(".").getAbsolutePath() + "/res/splashScreen.png";
public SplashScreen2() {
JFrame frame = new JFrame();
frame.getContentPane().add(new ImagePanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setUndecorated(true);
//The following doesnt work
frame.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
System.out.println("Pressed");
}
@Override
public void mouseReleased(MouseEvent e) {
System.out.println("Pressed");
}
});
frame.pack();
frame.setLocationRelativeTo(null);
frame.setBackground(new Color(0, 0, 0, 0));
frame.setVisible(true);
try {
Thread.sleep(5000);
frame.dispose();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new SplashScreen2();
}
});
}
@SuppressWarnings("serial")
public class ImagePanel extends JPanel {
BufferedImage img;
public ImagePanel() {
setOpaque(false);
setLayout(new GridBagLayout());
try {
img = ImageIO.read(new File(IMAGE_LOCATION));
} catch (IOException ex) {
ex.printStackTrace();
}
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(img, 0, 0, getWidth(), getHeight(), this);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(1080 / 2, 720 / 2);
}
}
}
结果如下:
您应该将侦听器添加到您的 ImagePanel
ImagePanel panel = new ImagePanel();
panel.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
System.out.println("Pressed");
}
@Override
public void mouseReleased(MouseEvent e) {
System.out.println("Pressed");
}
});
frame.add(panel);
此外,Thread.sleep(5000);
不起作用,因为您这样做了:
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new SplashScreen2();
}
});
您在事件调度线程上调用了构造函数,当您阻塞它时,将不会调度鼠标事件。