com.sciencegadgets.client.ui.FitParentHTML.java Source code

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Here is the source code for com.sciencegadgets.client.ui.FitParentHTML.java

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/*******************************************************************************
 *     This file is part of ScienceGadgets, a collection of educational tools
 *     Copyright (C) 2012-2015 by John Gralyan
 *
 *     ScienceGadgets is free software: you can redistribute it and/or modify
 *     it under the terms of the GNU Affero General Public License as
 *     published by the Free Software Foundation, either version 3 of
 *     the License, or (at your option) any later version.
 *
 *     ScienceGadgets is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU Affero General Public License for more details.
 *
 *     You should have received a copy of the GNU Affero General Public License
 *     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *     
 *     Contact us at info@sciencegadgets.org
 *******************************************************************************/
package com.sciencegadgets.client.ui;

import com.google.gwt.core.client.Scheduler;
import com.google.gwt.core.client.Scheduler.ScheduledCommand;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.Style;
import com.google.gwt.dom.client.Style.Unit;
import com.google.gwt.dom.client.Style.Visibility;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Widget;
import com.sciencegadgets.client.Moderator;

public class FitParentHTML extends HTML implements Resizable, HasFitParentHTML {

    public static final int DEFAULT_PERCENT_OF_PARENT = 95;
    CommunistPanel commPanel = null;

    /**
     * Percent of the parent to fill. 100 would match the parent.
     */
    public int percentOfParent = DEFAULT_PERCENT_OF_PARENT;

    public FitParentHTML() {
        this("", DEFAULT_PERCENT_OF_PARENT);
    }

    public FitParentHTML(String html) {
        this(html, DEFAULT_PERCENT_OF_PARENT);
    }

    public FitParentHTML(int percentOfParent) {
        this("", percentOfParent);
    }

    public FitParentHTML(String html, int percentOfParent) {
        super(html);
        this.percentOfParent = percentOfParent;
        addStyleName(CSS.FIT_PARENT_HTML);
    }

    void setPanel(CommunistPanel commPanel) {
        this.commPanel = commPanel;
    }

    @Override
    protected void onLoad() {
        getElement().getStyle().setVisibility(Visibility.HIDDEN);
        super.onLoad();
        Scheduler.get().scheduleDeferred(new ScheduledCommand() {
            @Override
            public void execute() {
                resize();
                getElement().getStyle().clearVisibility();
            }
        });
        Moderator.resizables.add(this);
    }

    @Override
    protected void onDetach() {
        super.onDetach();
        Moderator.resizables.remove(this);
    }

    @Override
    public void resize() {

        if (this.getParent() == null) {
            return;
        }
        if (commPanel == null) {
            resizeThis(getFontPercent());
            return;
        }

        commPanel.sizes.add(getFontPercent());

        if (commPanel.sizes.size() == commPanel.getWidgetCount()) {
            double smallest = commPanel.sizes.get(0);
            for (double size : commPanel.sizes) {
                smallest = Math.min(size, smallest);
            }
            int count = commPanel.getWidgetCount();
            for (int i = 0; i < count; i++) {
                Widget member = commPanel.getWidget(i);
                if (member instanceof HasFitParentHTML) {
                    FitParentHTML fit = ((HasFitParentHTML) member).getFitParentHTML();
                    if (fit != null) {
                        fit.resizeThis(smallest);
                    }

                }
            }
            commPanel.sizes.clear();
        }

    }

    private double getFontPercent() {

        if (this.getParent() == null) {
            return 100;
        }

        Element htmlElement = this.getElement();
        Style htmlStyle = htmlElement.getStyle();

        htmlStyle.clearPadding();
        htmlStyle.clearFontSize();

        Element parentElement = this.getParent().getElement();

        double widthRatio = (double) parentElement.getOffsetWidth() / (double) htmlElement.getOffsetWidth();
        double heightRatio = (double) parentElement.getOffsetHeight() / (double) htmlElement.getOffsetHeight();

        double smallerRatio = (widthRatio > heightRatio) ? heightRatio : widthRatio;

        // *percentOfParent for looser fit, *100 for percent
        return smallerRatio * percentOfParent;

    }

    private void resizeThis(double fontPercent) {
        Widget parent = this.getParent();
        if (parent == null) {
            return;
        }
        Element parentElement = parent.getElement();
        Element htmlElement = this.getElement();
        Style htmlStyle = htmlElement.getStyle();

        htmlStyle.setFontSize((fontPercent), Unit.PCT);

        // Center vertically
        double extraBottom = (double) parentElement.getOffsetHeight() - (double) htmlElement.getOffsetHeight();
        htmlStyle.setPaddingTop(extraBottom / 2, Unit.PX);

    }

    @Override
    public FitParentHTML getFitParentHTML() {
        return this;
    }
}