ImageResourceUtils.java

// Copyright 2012 Google Inc. All Rights Reserved.
//
// 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 org.eclipse.che.ide.util;

import elemental.css.CSSStyleDeclaration;
import elemental.html.DivElement;
import elemental.dom.Element;

import org.eclipse.che.ide.util.dom.Elements;
import com.google.gwt.resources.client.ImageResource;

/** Utilities for applying {@link com.google.gwt.resources.client.ImageResource}s to elements. */
public class ImageResourceUtils {

    /**
     * Applies the image resource to the specified element. The image will be
     * centered, and the height and width will be set to the height and width of
     * the image.
     */
    public static void applyImageResource(Element elem, ImageResource image) {
        applyImageResource(elem, image, "center", "center");
        elem.getStyle().setHeight(image.getHeight(), "px");
        elem.getStyle().setWidth(image.getWidth(), "px");
    }

    /**
     * Applies the image resource to the specified element with the specified
     * horizontal and vertical background positions.
     * <p/>
     * The height and width of the element are not modified under the presumption
     * that if you specify the horizontal and vertical position, the image will
     * not be the only content of the element.
     */
    public static void applyImageResource(Element elem, ImageResource image, String hPos,
                                          String vPos) {
        CSSStyleDeclaration style = elem.getStyle();
        style.setBackgroundImage("url(" + image.getSafeUri().asString() + ")");
        style.setProperty("background-repeat", "no-repeat");
        style.setProperty("background-position", hPos + " " + vPos);
        style.setOverflow("hidden");
    }

    /** Creates a div from the specified {@link com.google.gwt.resources.client.ImageResource}. */
    public static DivElement createImageElement(ImageResource image) {
        DivElement elem = Elements.createDivElement();
        applyImageResource(elem, image);
        return elem;
    }
}