001package gwt.material.design.client.base;
002
003/*
004 * #%L
005 * GwtMaterial
006 * %%
007 * Copyright (C) 2015 GwtMaterialDesign
008 * %%
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 * 
013 *      http://www.apache.org/licenses/LICENSE-2.0
014 * 
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 * #L%
021 */
022
023import gwt.material.design.client.ui.MaterialNumberBox;
024
025import java.io.IOException;
026import java.text.ParseException;
027
028import com.google.gwt.dom.client.Document;
029import com.google.gwt.text.shared.Parser;
030import com.google.gwt.text.shared.Renderer;
031import com.google.gwt.user.client.ui.ValueBox;
032
033/**
034 * Base class to handle number values on {@code <input type="number">} elements.
035 * 
036 * The parsing and formatting is done by the browser, using the user specific i18n settings.
037 * 
038 * @author gilberto-torrezan
039 * 
040 * @see MaterialNumberBox
041 */
042@SuppressWarnings({ "rawtypes", "unchecked" })
043public class NumberBox<T> extends ValueBox<T> {
044
045    public NumberBox(NumberHandler handler) {
046        // currently there's no way to create a <input type="number"> directly
047        super(Document.get().createTextInputElement(), handler, handler);
048    }
049
050    public static class NumberHandler<T> implements Renderer<T>, Parser<T> {
051
052        MaterialNumberBox<T> numberBox;
053
054        public NumberHandler(MaterialNumberBox<T> numberBox) {
055            this.numberBox = numberBox;
056        }
057
058        /*
059         * Note: This assumes that getValue() from the custom MaterialNumberBox was overridden to avoid using the parser.
060         */
061        @Override
062        public T parse(CharSequence text) throws ParseException {
063            return numberBox.getValue();
064        }
065
066        @Override
067        public String render(T object) {
068            if(object == null) {
069                return "";
070            }
071            return object.toString();
072        }
073
074        @Override
075        public void render(T object, Appendable appendable) throws IOException {
076            appendable.append(render(object));
077        }
078    }
079
080}