public void run() { while (running) { updateGame(); repaint(); try Thread.sleep(30); catch (InterruptedException e) {} } }
// Or via TouchEvent listener: TouchDevice.addListener(touchListener); They support standard pointerPressed reliably. No extra JAR needed. Defensive detection pattern: public boolean isTouchSupported() { try Class.forName("com.nokia.mid.ui.TouchEvent"); return true; catch (ClassNotFoundException e) {} // Also test if pointerPressed works: return getClass().getMethod("pointerPressed", int.class, int.class) != null; // rough } Better: check touch capability via Canvas.hasPointerEvents() (midp 2.0) – but that returns false if not supported. java midp 2.0 touch screen games
Use timestamps: record press time, check in update loop. 5. Graphics & Double Buffering for Touch Response Touch games must feel instant – input to visual feedback < 100ms. Enable double buffering: public class GameCanvas extends Canvas private Image offscreen; private Graphics offGfx; protected void sizeChanged(int w, int h) offscreen = Image.createImage(w, h); offGfx = offscreen.getGraphics(); public void run() { while (running) { updateGame();
protected void paint(Graphics g) g.setColor(0); g.fillRect(0, 0, getWidth(), getHeight()); g.setColor(0x00FF00); g.fillRect(playerX - 10, playerY - 10, 20, 20); drawBullets(g); // ... bullet management methods } Use timestamps: record press time, check in update loop
protected void pointerPressed(int x, int y) touching = true; touchX = x; touchY = y; onTouchDown(x, y);