com.ejt.vaadin.sizereporter.shared.SizeReporterConnector.java Source code

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Here is the source code for com.ejt.vaadin.sizereporter.shared.SizeReporterConnector.java

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/*
 * Copyright 2013 Ingo Kegel
 *
 * 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.ejt.vaadin.sizereporter.shared;

import com.ejt.vaadin.sizereporter.SizeReporter;
import com.google.gwt.event.dom.client.HasLoadHandlers;
import com.google.gwt.event.dom.client.LoadEvent;
import com.google.gwt.event.dom.client.LoadHandler;
import com.google.gwt.user.client.ui.Widget;
import com.vaadin.client.ComponentConnector;
import com.vaadin.client.LayoutManager;
import com.vaadin.client.ServerConnector;
import com.vaadin.client.extensions.AbstractExtensionConnector;
import com.vaadin.client.ui.layout.ElementResizeEvent;
import com.vaadin.client.ui.layout.ElementResizeListener;
import com.vaadin.shared.ui.Connect;

@Connect(SizeReporter.class)
public class SizeReporterConnector extends AbstractExtensionConnector {

    private SizeReporterRpc sizeReporterRpc;
    private Widget widget;

    @Override
    protected void init() {
        super.init();
        sizeReporterRpc = getRpcProxy(SizeReporterRpc.class);
    }

    @Override
    protected void extend(ServerConnector target) {
        if (target instanceof ComponentConnector) {
            widget = ((ComponentConnector) target).getWidget();

            if (widget.getOffsetWidth() > 0 && widget.getOffsetHeight() > 0) {
                reportSize(); // for widgets already in the layout
            }

            // ElementResizeListener does not work for widgets that are 'loaded' (e.g. Image...)
            if (widget instanceof HasLoadHandlers) {
                ((HasLoadHandlers) widget).addLoadHandler(new LoadHandler() {
                    @Override
                    public void onLoad(LoadEvent event) {
                        reportSize();
                    }
                });
            } else {
                LayoutManager.get(getConnection()).addElementResizeListener(widget.getElement(),
                        new ElementResizeListener() {
                            @Override
                            public void onElementResize(ElementResizeEvent event) {
                                reportSize();
                            }
                        });
            }
        }
    }

    private void reportSize() {
        sizeReporterRpc.sizeChanged(widget.getOffsetWidth(), widget.getOffsetHeight());
    }

}