The import javax.mail. Swing. JFrame;
The import javax.mail. Swing. WindowConstants;

Public class GameFrame {
Public static void main (String [] args) {
JFrame j1=new JFrame ();
J1. SetVisible (true);
J1. SetBounds (100100570613);
J1. SetDefaultCloseOperation (WindowConstants. EXIT_ON_CLOSE);
J1. Add (new GamePanel ());
}

}




Import the Java. The awt. Event. KeyAdapter;
Import the Java. The awt. Event. KeyEvent;
The import javax.mail. Swing. JPanel;

Public class GamePanel extends JPanel {
Public GamePanel () {
Enclosing addKeyListener (new Listen ());
}
The class Listen extends KeyAdapter {
@ Override
Public void keyPressed KeyEvent (e) {
If (um participant etKeyCode ()==KeyEvent. VK_SPACE) {
System. The out. Println (" press the blank space ");
}
}
}}

CodePudding user response:

If not mistaken, you have to use anonymous inner class can solve,
[KeyEvent anonymous inner class] baidu casually, gather together go to see
https://blog.csdn.net/LeoZuosj/article/details/104230051
They could be a direction for check

CodePudding user response:

Because your GamePanel can't focus, a component to respond to events get focus first, otherwise the events of the components will only others are focusing on GamePanel rather than you,
You can modify the main method
GamePanel gp=new GamePanel ();
J1. Add (gp);//can best j1 setLayout
If (gp) isFocusable ()) {
Gp. RequestFocuse ();//take the initiative to get focus
}

CodePudding user response:

The

refer to the original poster weixin_44852871 response:

import javax.mail. Swing. The JFrame.
The import javax.mail. Swing. WindowConstants;

Public class GameFrame {
Public static void main (String [] args) {
JFrame j1=new JFrame ();
J1. SetVisible (true);
J1. SetBounds (100100570613);
J1. SetDefaultCloseOperation (WindowConstants. EXIT_ON_CLOSE);
J1. Add (new GamePanel ());
}

}




Import the Java. The awt. Event. KeyAdapter;
Import the Java. The awt. Event. KeyEvent;
The import javax.mail. Swing. JPanel;

Public class GamePanel extends JPanel {
Public GamePanel () {
Enclosing addKeyListener (new Listen ());
}
The class Listen extends KeyAdapter {
@ Override
Public void keyPressed KeyEvent (e) {
If (um participant etKeyCode ()==KeyEvent. VK_SPACE) {
System. The out. Println (" press the blank space ");
}
}
}}

You use this addKeyListener is wrong;

 
JFrame jf=new JFrame (); 

Jf. AddKeyListener (new KeyListener () {
@ Override 
Public void keyPressed KeyEvent (e) {
//access keys, and KeyEvent VK_XXXX constant comparison by press the button 
Int keyCode=um participant etKeyCode (); 
System. The out. Println (" press: "+ um participant etKeyCode ()); 
} 

@ Override 
Public void keyTyped KeyEvent (e) {
//um participant etKeyChar () a character type 
System. The out. Println (" type: "+ um participant etKeyChar ()); 
} 

@ Override 
Public void keyReleased KeyEvent (e) {
System. The out. Println (" release: "+ um participant etKeyCode ()); 
} 
});