VNavigationButton.java

package org.vaadin.touchkit.gwt.client.ui;

import java.util.Date;

import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.dom.client.SpanElement;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.TouchCancelEvent;
import com.google.gwt.event.dom.client.TouchCancelHandler;
import com.google.gwt.event.dom.client.TouchEndEvent;
import com.google.gwt.event.dom.client.TouchEndHandler;
import com.google.gwt.event.dom.client.TouchMoveEvent;
import com.google.gwt.event.dom.client.TouchMoveHandler;
import com.google.gwt.event.dom.client.TouchStartEvent;
import com.google.gwt.event.dom.client.TouchStartHandler;
import com.google.gwt.user.client.Window.Navigator;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Widget;
import com.vaadin.client.ui.Icon;

public class VNavigationButton extends HTML implements TouchStartHandler,
        TouchCancelHandler, TouchEndHandler, TouchMoveHandler, ClickHandler {
    private static final String NAVBUTTON_CLASSNAME = "v-touchkit-navbutton";
    private String caption;
    private Icon icon;
    private SpanElement descriptionElement;
    private boolean enabled;
    static final long IGNORE_SIMULATED_CLICKS_THRESHOLD = 1500;
    private boolean touchStarted = false;
    private Date fastClickAt;

    // TODO check if WP could support fast clicks as well. Now seem to get
    // duplicate events every now and then
    public static boolean useFastClicks = !Navigator.getUserAgent()
            .toLowerCase().contains("android 2");

    public VNavigationButton() {
        setStyleName(NAVBUTTON_CLASSNAME);
        if (VNavigationButton.useFastClicks) {
            addTouchStartHandler(this);
            addTouchCancelHandler(this);
            addTouchEndHandler(this);
            addTouchMoveHandler(this);
        }
        addClickHandler(this);
    }

    public VNavigationManager findNavigationPanel() {
        Widget parent2 = getParent();
        while (parent2 != null && !(parent2 instanceof VNavigationManager)) {
            parent2 = parent2.getParent();
        }
        return (VNavigationManager) parent2;
    }

    @Override
    public void setText(String text) {
        caption = text;
        super.setText(text);
    }

    public String getCaption() {
        return caption;
    }

    public void setIcon(Icon newIcon) {
        if (newIcon == null) {
            if (icon != null) {
                getElement().removeChild(icon.getElement());
            }
        } else if (icon != null
        // icon might have been removed by a call to #setText (#14536)
                && getElement().isOrHasChild(icon.getElement())) {
            getElement().replaceChild(icon.getElement(), newIcon.getElement());
        } else {
            getElement().insertFirst(newIcon.getElement());
        }
        icon = newIcon;
    }

    public void setDescription(String description) {
        if (description != null && !description.trim().isEmpty()) {
            if (descriptionElement == null) {
                descriptionElement = Document.get().createSpanElement();
                descriptionElement.setClassName(NAVBUTTON_CLASSNAME + "-desc");
            }
            /*
             * Add the descriptionElement if it's not already added as it might
             * have been overwritten by a call to #setText
             */
            if (!getElement().isOrHasChild(descriptionElement)) {
                getElement().insertFirst(descriptionElement);
            }
            descriptionElement.setInnerHTML(description);

        } else if (descriptionElement != null) {
            descriptionElement.removeFromParent();
            descriptionElement = null;
        }
    }

    @Override
    public void onTouchMove(TouchMoveEvent event) {
        touchStarted = false;
    }

    @Override
    public void onTouchEnd(TouchEndEvent event) {
        if (touchStarted) {
            event.preventDefault();
            event.stopPropagation();
            NativeEvent nativeEvent = event.getNativeEvent();
            NativeEvent evt = Document.get().createClickEvent(1,
                    nativeEvent.getScreenX(), nativeEvent.getScreenY(),
                    nativeEvent.getClientX(), nativeEvent.getClientY(), false,
                    false, false, false);
            getElement().dispatchEvent(evt);
            touchStarted = false;
            fastClickAt = new Date();
        }
    }

    @Override
    public void onTouchCancel(TouchCancelEvent event) {
        touchStarted = false;
    }

    @Override
    public void onTouchStart(TouchStartEvent event) {
        touchStarted = true;
        fastClickAt = null;
        getElement().focus();
    }

    @Override
    public void onClick(ClickEvent event) {
        if (enabled) {
            if (fastClickAt != null
                    && (new Date().getTime() - fastClickAt.getTime()) < IGNORE_SIMULATED_CLICKS_THRESHOLD) {
                // VConsole.log("Ignored simulated event fired by old ios or android "
                // + (new Date().getTime() - fastClickAt.getTime()));
                fastClickAt = null;
                return;
            }
            getElement().focus();
        }
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public boolean isEnabled() {
        return enabled;
    }

}