org.eclipse.osbp.vaadin.addons.keyevents/src/org/eclipse/osbp/vaadin/addons/keyevents/client/KeyEventExtensionConnector.java

package org.eclipse.osbp.vaadin.addons.keyevents.client;

import java.util.HashMap;
import java.util.Map;

import org.eclipse.osbp.vaadin.addons.keyevents.KeyEventExtension;

import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.Event.NativePreviewEvent;
import com.google.gwt.user.client.Event.NativePreviewHandler;
import com.vaadin.client.ServerConnector;
import com.vaadin.client.VConsole;
import com.vaadin.client.communication.RpcProxy;
import com.vaadin.client.extensions.AbstractExtensionConnector;
import com.vaadin.event.ShortcutAction.KeyCode;
import com.vaadin.event.ShortcutAction.ModifierKey;
import com.vaadin.shared.ui.Connect;

@SuppressWarnings("serial")
@Connect(KeyEventExtension.class)
public class KeyEventExtensionConnector extends AbstractExtensionConnector {

	private KeyEventServerRpc serverRPC = RpcProxy.create(KeyEventServerRpc.class, this);
	private HandlerRegistration handlerRegistration;
	protected Map<Integer, String> unkeyMapper = new HashMap<Integer, String>() {
		private static final long serialVersionUID = 8801421284339992078L;
		{
			put(KeyCode.ARROW_DOWN, "ARROW_DOWN");
			put(KeyCode.ARROW_LEFT, "ARROW_LEFT");
			put(KeyCode.ARROW_RIGHT, "ARROW_RIGHT");
			put(KeyCode.ARROW_UP, "ARROW_UP");
			put(KeyCode.HOME, "HOME");
			put(KeyCode.END, "END");
			put(KeyCode.DELETE, "DELETE");
			put(KeyCode.BACKSPACE, "BACKSPACE");
			put(ModifierKey.ALT, "ALT");
			put(ModifierKey.SHIFT, "SHIFT");
			put(ModifierKey.CTRL, "CTRL");
			put(ModifierKey.META, "META");
		}
	};

	@Override
	protected void init() {
		super.init();

		handlerRegistration = com.google.gwt.user.client.Event.addNativePreviewHandler(new NativePreviewHandler() {
			@Override
			public void onPreviewNativeEvent(NativePreviewEvent nativePreviewEvent) {
				switch (nativePreviewEvent.getTypeInt()) {
				case com.google.gwt.user.client.Event.ONKEYUP:
					final Event event = createEvent(nativePreviewEvent.getNativeEvent());
					if (!unkeyMapper.containsKey(event.charCode)) {
						serverRPC.onKeyPress(event);
						nativePreviewEvent.cancel();
					}
					break;
				}

			}
		});
	}

	public void onUnregister() {
		super.onUnregister();

		if (handlerRegistration != null) {
			VConsole.log("Unregister handlerRegistratio for keyEvents");
			handlerRegistration.removeHandler();
		}
	}

	@Override
	protected void extend(final ServerConnector connector) {
		// NOOP
	}

	protected Event createEvent(NativeEvent event) {
		Event e = new Event();
		e.charCode = event.getKeyCode();
		e.altKeyDown = event.getAltKey();
		e.controlKeyDown = event.getCtrlKey();
		e.metaKeyDown = event.getMetaKey();
		e.shiftKeyDown = event.getShiftKey();
		return e;
	}

}