Why is My KeyListener Not Responding in My JFrame?
Nov 11, 2024 am 08:56 AMUnresponsive KeyListener for JFrame: Using a KeyEventDispatcher
You're experiencing an unresponsive KeyListener because the focus might not be on the JFrame. To address this, consider adding a separate KeyEventDispatcher to the KeyboardFocusManager.
In the following code example, a MyDispatcher class is defined and added to the KeyboardFocusManager:
public class MyFrame extends JFrame { private class MyDispatcher implements KeyEventDispatcher { @Override public boolean dispatchKeyEvent(KeyEvent e) { if (e.getID() == KeyEvent.KEY_PRESSED) { System.out.println("tester"); } else if (e.getID() == KeyEvent.KEY_RELEASED) { System.out.println("2test2"); } else if (e.getID() == KeyEvent.KEY_TYPED) { System.out.println("3test3"); } return false; } } public MyFrame() { add(new JTextField()); System.out.println("test"); KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager(); manager.addKeyEventDispatcher(new MyDispatcher()); } public static void main(String[] args) { MyFrame f = new MyFrame(); f.pack(); f.setVisible(true); } }
This dispatcher handles all key events regardless of component focus, printing messages to the console. This approach ensures that your KeyListener will receive keyboard input even if the focus is not directly on the JFrame.
The above is the detailed content of Why is My KeyListener Not Responding in My JFrame?. For more information, please follow other related articles on the PHP Chinese website!

Hot Article

Hot tools Tags

Hot Article

Hot Article Tags

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

Top 4 JavaScript Frameworks in 2025: React, Angular, Vue, Svelte

How does Java's classloading mechanism work, including different classloaders and their delegation models?

How do I use Maven or Gradle for advanced Java project management, build automation, and dependency resolution?

Node.js 20: Key Performance Boosts and New Features

Iceberg: The Future of Data Lake Tables

How do I implement multi-level caching in Java applications using libraries like Caffeine or Guava Cache?

Spring Boot SnakeYAML 2.0 CVE-2022-1471 Issue Fixed

How to Share Data Between Steps in Cucumber
