// This example is from _Java Examples in a Nutshell_. (http://www.oreilly.com) // Copyright (c) 1997 by David Flanagan // This example is provided WITHOUT ANY WARRANTY either expressed or implied. // You may study, use, modify, and distribute it for non-commercial purposes. // For any commercial use, see http://www.davidflanagan.com/javaexamples import java.applet.*; import java.awt.*; import java.awt.event.*; import java.util.*; /** A program that displays all the event that occur in its window */ public class EventTester2 extends Frame { /** The main method: create an EventTester frame, and pop it up */ public static void main(String[] args) { EventTester2 et = new EventTester2(); et.setSize(500, 400); et.show(); } /** The constructor: register the event types we are interested in */ public EventTester2() { super("Event Tester"); this.enableEvents(AWTEvent.MOUSE_EVENT_MASK | AWTEvent.MOUSE_MOTION_EVENT_MASK | AWTEvent.KEY_EVENT_MASK | AWTEvent.FOCUS_EVENT_MASK | AWTEvent.COMPONENT_EVENT_MASK | AWTEvent.WINDOW_EVENT_MASK); } /** * Display mouse events that don't involve mouse motion. * The mousemods() method prints modifiers, and is defined below. * The other methods return additional information about the mouse event. * showLine() displays a line of text in the window. It is defined * at the end of this class, along with the paint() method. */ public void processMouseEvent(MouseEvent e) { String type = null; switch(e.getID()) { case MouseEvent.MOUSE_PRESSED: type = "MOUSE_PRESSED"; break; case MouseEvent.MOUSE_RELEASED: type = "MOUSE_RELEASED"; break; case MouseEvent.MOUSE_CLICKED: type = "MOUSE_CLICKED"; break; case MouseEvent.MOUSE_ENTERED: type = "MOUSE_ENTERED"; break; case MouseEvent.MOUSE_EXITED: type = "MOUSE_EXITED"; break; } showLine(mousemods(e) + type + ": [" + e.getX() + "," + e.getY() + "] " + "num clicks = " + e.getClickCount() + (e.isPopupTrigger()?"; is popup trigger":"")); } /** * Display mouse moved and dragged mouse event. Note that MouseEvent * is the only event type that has two methods, two EventListener interfaces * and two adapter classes to handle two distinct categories of events. * Also, as seen in init(), mouse motion events must be requested * separately from other mouse event types. */ public void processMouseMotionEvent(MouseEvent e) { String type = null; switch(e.getID()) { case MouseEvent.MOUSE_MOVED: type = "MOUSE_MOVED"; break; case MouseEvent.MOUSE_DRAGGED: type = "MOUSE_DRAGGED"; break; } showLine(mousemods(e) + type + ": [" + e.getX() + "," + e.getY() + "] " + "num clicks = " + e.getClickCount() + (e.isPopupTrigger()?"; is popup trigger":"")); } /** Return a string representation of the modifiers for a MouseEvent. * Note that the methods called here are inherited from InputEvent. */ protected String mousemods(MouseEvent e) { int mods = e.getModifiers(); String s = ""; if (e.isShiftDown()) s += "Shift "; if (e.isControlDown()) s += "Ctrl "; if ((mods & InputEvent.BUTTON1_MASK) != 0) s += "Button 1 "; if ((mods & InputEvent.BUTTON2_MASK) != 0) s += "Button 2 "; if ((mods & InputEvent.BUTTON3_MASK) != 0) s += "Button 3 "; return s; } /** * Display keyboard events. * Note that there are three distinct types of key events, and that * key events are reported by key code and/or Unicode character. * KEY_PRESSED and KEY_RELEASED events are generated for all key strokes. * KEY_TYPED events are only generated when a key stroke produces a * Unicode character; these events do not report a key code. * If isActionKey() returns true, then the key event reports only * a key code, because the key that was pressed or released (such as a * function key) has no corresponding Unicode character. * Key codes can be interpreted by using the many VK_ constants defined * by the KeyEvent class, or they can be converted to strings using * the static getKeyText() method as we do here. */ public void processKeyEvent(KeyEvent e) { String eventtype, modifiers, code, character; switch(e.getID()) { case KeyEvent.KEY_PRESSED: eventtype = "KEY_PRESSED"; break; case KeyEvent.KEY_RELEASED: eventtype = "KEY_RELEASED"; break; case KeyEvent.KEY_TYPED: eventtype = "KEY_TYPED"; break; default: eventtype = "UNKNOWN"; } // Convert the list of modifier keys to a string modifiers = KeyEvent.getKeyModifiersText(e.getModifiers()); // Get string and numeric versions of the key code, if any. if (e.getID() == KeyEvent.KEY_TYPED) code = ""; else code = "Code=" + KeyEvent.getKeyText(e.getKeyCode()) + " (" + e.getKeyCode() + ")"; // Get string and numeric versions of the Unicode character, if any. if (e.isActionKey()) character = ""; else character = "Character=" + e.getKeyChar() + " (Unicode=" + ((int)e.getKeyChar()) + ")"; // Display it all. showLine(eventtype + ": " + modifiers + " " + code + " " + character); } /** Display keyboard focus events. Focus can be permanently * gained or lost, or temporarily transferred to or from a component. */ public void processFocusEvent(FocusEvent e) { if (e.getID() == FocusEvent.FOCUS_GAINED) showLine("FOCUS_GAINED" + (e.isTemporary()?" (temporary)":"")); else showLine("FOCUS_LOST" + (e.isTemporary()?" (temporary)":"")); } /** Display Component events. */ public void processComponentEvent(ComponentEvent e) { switch(e.getID()) { case ComponentEvent.COMPONENT_MOVED: showLine("COMPONENT_MOVED"); break; case ComponentEvent.COMPONENT_RESIZED: showLine("COMPONENT_RESIZED");break; case ComponentEvent.COMPONENT_HIDDEN: showLine("COMPONENT_HIDDEN"); break; case ComponentEvent.COMPONENT_SHOWN: showLine("COMPONENT_SHOWN"); break; } } /** Display Window events. Note the special handling of WINDOW_CLOSING */ public void processWindowEvent(WindowEvent e) { switch(e.getID()) { case WindowEvent.WINDOW_OPENED: showLine("WINDOW_OPENED"); break; case WindowEvent.WINDOW_CLOSED: showLine("WINDOW_CLOSED"); break; case WindowEvent.WINDOW_CLOSING: showLine("WINDOW_CLOSING"); break; case WindowEvent.WINDOW_ICONIFIED: showLine("WINDOW_ICONIFIED"); break; case WindowEvent.WINDOW_DEICONIFIED: showLine("WINDOW_DEICONIFIED"); break; case WindowEvent.WINDOW_ACTIVATED: showLine("WINDOW_ACTIVATED"); break; case WindowEvent.WINDOW_DEACTIVATED: showLine("WINDOW_DEACTIVATED"); break; } // If the user requested a window close, quit the program. // But first display a message, force it to be visible, and make // sure the user has time to read it. if (e.getID() == WindowEvent.WINDOW_CLOSING) { showLine("WINDOW_CLOSING event received."); showLine("Application will exit in 5 seconds"); update(this.getGraphics()); try {Thread.sleep(5000);} catch (InterruptedException ie) { ; } System.exit(0); } } /** The list of lines to display in the window */ protected Vector lines = new Vector(); /** Add a new line to the list of lines, and redisplay */ protected void showLine(String s) { if (lines.size() == 20) lines.removeElementAt(0); lines.addElement(s); repaint(); } /** This method repaints the text in the window */ public void paint(Graphics g) { for(int i = 0; i < lines.size(); i++) g.drawString((String)lines.elementAt(i), 20, i*16 + 50); } }