Java tutorial
/* * Copyright 2000-2018 Vaadin Ltd. * * 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.vaadin.client.ui; import com.google.gwt.core.client.Scheduler; import com.google.gwt.dom.client.Element; import com.google.gwt.dom.client.Style.Visibility; import com.google.gwt.user.client.DOM; import com.google.gwt.user.client.Event; import com.vaadin.client.ApplicationConnection; import com.vaadin.client.BrowserInfo; import com.vaadin.client.Util; import com.vaadin.client.VTooltip; import com.vaadin.client.WidgetUtil.ErrorUtil; import com.vaadin.client.ui.aria.AriaHelper; import com.vaadin.client.ui.aria.HandlesAriaInvalid; import com.vaadin.client.ui.aria.HandlesAriaRequired; public class VCheckBox extends com.google.gwt.user.client.ui.CheckBox implements Field, HandlesAriaInvalid, HandlesAriaRequired, HasErrorIndicatorElement { public static final String CLASSNAME = "v-checkbox"; /** For internal use only. May be removed or replaced in the future. */ public String id; /** For internal use only. May be removed or replaced in the future. */ public ApplicationConnection client; /** For internal use only. May be removed or replaced in the future. */ private Element errorIndicatorElement; /** For internal use only. May be removed or replaced in the future. */ public Icon icon; public VCheckBox() { setStyleName(CLASSNAME); Element el = DOM.getFirstChild(getElement()); while (el != null) { DOM.sinkEvents(el, DOM.getEventsSunk(el) | VTooltip.TOOLTIP_EVENTS); el = DOM.getNextSibling(el); } if (BrowserInfo.get().isWebkit() || BrowserInfo.get().isFirefox()) { // Webkit and Firefox do not focus non-text input elements on click // (#3944) addClickHandler(event -> setFocus(true)); } } @Override public void onBrowserEvent(Event event) { if (icon != null && event.getTypeInt() == Event.ONCLICK && DOM.eventGetTarget(event) == icon.getElement()) { // Click on icon should do nothing if widget is disabled if (isEnabled()) { setValue(!getValue()); } } super.onBrowserEvent(event); if (event.getTypeInt() == Event.ONLOAD) { Util.notifyParentOfSizeChange(this, true); } } /** * Gives access to the input element. * * @return Element of the CheckBox itself * @since 8.7 */ public Element getInputElement() { // public to allow CheckBoxState to access it. // FIXME: Would love to use a better way to access the checkbox element return getElement().getFirstChildElement(); } /** * Gives access to the label element. * * @return Element of the Label itself * @since 8.7 */ public Element getLabelElement() { // public to allow CheckBoxState to access it. // FIXME: Would love to use a better way to access the label element return getInputElement().getNextSiblingElement(); } @Override public void setAriaRequired(boolean required) { AriaHelper.handleInputRequired(getInputElement(), required); } @Override public void setAriaInvalid(boolean invalid) { AriaHelper.handleInputInvalid(getInputElement(), invalid); } @Override public Element getErrorIndicatorElement() { return errorIndicatorElement; } @Override public void setErrorIndicatorElementVisible(boolean visible) { if (visible) { if (errorIndicatorElement == null) { errorIndicatorElement = ErrorUtil.createErrorIndicatorElement(); getElement().appendChild(errorIndicatorElement); DOM.sinkEvents(errorIndicatorElement, VTooltip.TOOLTIP_EVENTS | Event.ONCLICK); } } else if (errorIndicatorElement != null) { getElement().removeChild(errorIndicatorElement); errorIndicatorElement = null; } } @Override protected void onAttach() { super.onAttach(); if (BrowserInfo.get().isSafari()) { /* * Sometimes Safari does not render checkbox correctly when * attaching. Setting the visibility to hidden and a bit later * restoring will make everything just fine. */ getElement().getStyle().setVisibility(Visibility.HIDDEN); Scheduler.get().scheduleFinally(() -> { getElement().getStyle().setVisibility(Visibility.VISIBLE); }); } } }