com.google.gwt.query.client.plugins.widgets.WidgetsUtils.java Source code

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Here is the source code for com.google.gwt.query.client.plugins.widgets.WidgetsUtils.java

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/*
 * Copyright 2011, The gwtquery team.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.query.client.plugins.widgets;

import static com.google.gwt.query.client.GQuery.$;

import com.google.gwt.dom.client.BodyElement;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.Element;
import com.google.gwt.query.client.GQuery;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.ui.ComplexPanel;
import com.google.gwt.user.client.ui.GqUi;
import com.google.gwt.user.client.ui.HTMLPanel;
import com.google.gwt.user.client.ui.Panel;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.Widget;

public class WidgetsUtils {

    static final String[] appendingTags = { "td", "th", "li" };

    /**
      * Append a widget to a dom element, and hide it.
      * Element classes will be copied to the new widget.
      */
    public static void hideAndAfter(Element e, Widget widget) {
        assert e != null && widget != null;
        if ($(e).widget() != null && $(e).widget().isAttached()) {
            replaceWidget($(e).widget(), widget, false);
        } else {
            GqUi.detachWidget(widget);
            hideAndAfter(e, widget.getElement());
            GqUi.attachWidget(widget, getFirstParentWidget(widget));
        }
    }

    /**
     * Test if the tag name of the element is one of tag names given in parameter
     * 
     * @param tagNames
     * @return
     */
    public static boolean matchesTags(Element e, String... tagNames) {

        assert e != null : "Element cannot be null";

        StringBuilder regExp = new StringBuilder("^(");
        int tagNameLenght = tagNames != null ? tagNames.length : 0;
        for (int i = 0; i < tagNameLenght; i++) {
            regExp.append(tagNames[i].toUpperCase());
            if (i < tagNameLenght - 1) {
                regExp.append("|");
            }
        }
        regExp.append(")$");

        return e.getTagName().toUpperCase().matches(regExp.toString());

    }

    /**
     * Replace a dom element by a widget.
     * Old element classes will be copied to the new widget.
     */
    public static void replaceOrAppend(Element e, Widget widget) {
        assert e != null && widget != null;
        if ($(e).widget() != null && $(e).widget().isAttached()) {
            replaceWidget($(e).widget(), widget, true);
        } else {
            GqUi.detachWidget(widget);
            replaceOrAppend(e, widget.getElement());
            GqUi.attachWidget(widget, getFirstParentWidget(widget));
        }
    }

    private static Widget getFirstParentWidget(Widget w) {
        Element e = w.getElement().getParentElement();
        BodyElement body = Document.get().getBody();
        while ((e != null) && (body != e)) {
            if (Event.getEventListener(e) != null) {
                Widget p = $(e).widget();
                if (p != null) {
                    return p;
                }
            }
            e = e.getParentElement();
        }
        return null;
    }

    private static void hideAndAfter(Element oldElement, Element newElement) {
        assert oldElement != null && newElement != null;
        GQuery.$(oldElement).hide().after(newElement);
        String c = oldElement.getClassName();
        if (!c.isEmpty()) {
            newElement.addClassName(c);
        }
    }

    /**
    * If the <code>oldElement</code> is a td, th, li tags, the new element will replaced its content.
    * In other cases, the <code>oldElement</code> will be replaced by the <code>newElement</code>
    *  and the old element classes will be copied to the new element.
    */
    private static void replaceOrAppend(Element oldElement, Element newElement) {
        assert oldElement != null && newElement != null;

        if (matchesTags(oldElement, appendingTags)) {
            GQuery.$(oldElement).html("").append(newElement);
        } else {
            GQuery.$(oldElement).replaceWith(newElement);

            //copy class
            String c = oldElement.getClassName();
            if (!c.isEmpty()) {
                newElement.addClassName(c);
            }
            //copy id
            newElement.setId(oldElement.getId());
            //ensure no duplicate id
            oldElement.setId("");

        }
    }

    private static void replaceWidget(Widget oldWidget, Widget newWidget, boolean remove) {
        Widget parent = oldWidget.getParent();
        boolean removed = false;
        // TODO: handle tables
        if (parent instanceof HTMLPanel) {
            ((HTMLPanel) parent).addAndReplaceElement(newWidget, oldWidget.getElement());
            if (!remove) {
                $(newWidget).before($(oldWidget));
            }
            removed = true;
        } else if (parent instanceof ComplexPanel) {
            ((ComplexPanel) parent).add(newWidget);
        } else if (parent instanceof SimplePanel) {
            ((SimplePanel) parent).setWidget(newWidget);
        } else if (parent instanceof Panel) {
            ((Panel) parent).add(newWidget);
        } else {
            assert false : "Can not replace an attached widget whose parent is a " + parent.getClass().getName();
        }
        if (remove && !removed && oldWidget.isAttached()) {
            oldWidget.removeFromParent();
        } else {
            oldWidget.setVisible(false);
        }
    }
}