Java tutorial
/* * Copyright 2000-2016 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.v7.client.ui; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import com.google.gwt.aria.client.Roles; import com.google.gwt.core.client.Scheduler; import com.google.gwt.event.dom.client.BlurEvent; import com.google.gwt.event.dom.client.BlurHandler; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.event.dom.client.FocusEvent; import com.google.gwt.event.dom.client.FocusHandler; import com.google.gwt.event.dom.client.LoadEvent; import com.google.gwt.event.dom.client.LoadHandler; import com.google.gwt.event.shared.HandlerRegistration; import com.google.gwt.user.client.Command; import com.google.gwt.user.client.ui.CheckBox; import com.google.gwt.user.client.ui.FocusWidget; import com.google.gwt.user.client.ui.Focusable; import com.google.gwt.user.client.ui.HasEnabled; import com.google.gwt.user.client.ui.Panel; import com.google.gwt.user.client.ui.RadioButton; import com.google.gwt.user.client.ui.Widget; import com.vaadin.client.BrowserInfo; import com.vaadin.client.StyleConstants; import com.vaadin.client.UIDL; import com.vaadin.client.Util; import com.vaadin.client.WidgetUtil; import com.vaadin.client.ui.Icon; import com.vaadin.client.ui.VCheckBox; import com.vaadin.shared.EventId; import com.vaadin.v7.shared.ui.optiongroup.OptionGroupConstants; public class VOptionGroup extends VOptionGroupBase implements FocusHandler, BlurHandler { public static final String CLASSNAME = "v-select-optiongroup"; /** For internal use only. May be removed or replaced in the future. */ public final Panel panel; private final Map<CheckBox, String> optionsToKeys; private final Map<CheckBox, Boolean> optionsEnabled; /** For internal use only. May be removed or replaced in the future. */ public boolean sendFocusEvents = false; /** For internal use only. May be removed or replaced in the future. */ public boolean sendBlurEvents = false; /** For internal use only. May be removed or replaced in the future. */ public List<HandlerRegistration> focusHandlers = null; /** For internal use only. May be removed or replaced in the future. */ public List<HandlerRegistration> blurHandlers = null; private final LoadHandler iconLoadHandler = new LoadHandler() { @Override public void onLoad(LoadEvent event) { Util.notifyParentOfSizeChange(VOptionGroup.this, true); } }; /** * used to check whether a blur really was a blur of the complete * optiongroup: if a control inside this optiongroup gains focus right after * blur of another control inside this optiongroup (meaning: if onFocus * fires after onBlur has fired), the blur and focus won't be sent to the * server side as only a focus change inside this optiongroup occured */ private boolean blurOccured = false; private boolean htmlContentAllowed = false; private boolean wasHtmlContentAllowed = false; private boolean wasMultiselect = false; public VOptionGroup() { super(CLASSNAME); panel = (Panel) optionsContainer; optionsToKeys = new HashMap<>(); optionsEnabled = new HashMap<>(); wasMultiselect = isMultiselect(); } /* * Try to update content of existing elements, rebuild panel entirely * otherwise */ @Override public void buildOptions(UIDL uidl) { /* * In order to retain focus, we need to update values rather than * recreate panel from scratch (#10451). However, the panel will be * rebuilt (losing focus) if number of elements or their order is * changed. */ HashMap<String, CheckBox> keysToOptions = new HashMap<>(); for (Map.Entry<CheckBox, String> entry : optionsToKeys.entrySet()) { keysToOptions.put(entry.getValue(), entry.getKey()); } ArrayList<Widget> existingwidgets = new ArrayList<>(); ArrayList<Widget> newwidgets = new ArrayList<>(); // Get current order of elements for (Widget wid : panel) { existingwidgets.add(wid); } optionsEnabled.clear(); if (isMultiselect()) { Roles.getGroupRole().set(getElement()); } else { Roles.getRadiogroupRole().set(getElement()); } for (final Iterator<?> it = uidl.getChildIterator(); it.hasNext();) { final UIDL opUidl = (UIDL) it.next(); String itemHtml = opUidl.getStringAttribute("caption"); if (!isHtmlContentAllowed()) { itemHtml = WidgetUtil.escapeHTML(itemHtml); } String iconUrl = opUidl.getStringAttribute("icon"); if (iconUrl != null && iconUrl.length() != 0) { Icon icon = client.getIcon(iconUrl); itemHtml = icon.getElement().getString() + itemHtml; } String key = opUidl.getStringAttribute("key"); CheckBox op = keysToOptions.get(key); // Need to recreate object if isMultiselect is changed (#10451) // OR if htmlContentAllowed changed due to Safari 5 issue if ((op == null) || (isHtmlContentAllowed() != wasHtmlContentAllowed) || (isMultiselect() != wasMultiselect)) { // Create a new element if (isMultiselect()) { op = new VCheckBox(); } else { op = new RadioButton(paintableId); op.setStyleName("v-radiobutton"); } if (iconUrl != null && iconUrl.length() != 0) { WidgetUtil.sinkOnloadForImages(op.getElement()); op.addHandler(iconLoadHandler, LoadEvent.getType()); } op.addStyleName(CLASSNAME_OPTION); op.addClickHandler(this); optionsToKeys.put(op, key); } op.setHTML(itemHtml); op.setValue(opUidl.getBooleanAttribute("selected")); boolean optionEnabled = !opUidl.getBooleanAttribute(OptionGroupConstants.ATTRIBUTE_OPTION_DISABLED); boolean enabled = optionEnabled && !isReadonly() && isEnabled(); op.setEnabled(enabled); optionsEnabled.put(op, optionEnabled); setStyleName(op.getElement(), StyleConstants.DISABLED, !(optionEnabled && isEnabled())); newwidgets.add(op); } if (!newwidgets.equals(existingwidgets)) { // Rebuild the panel, losing focus panel.clear(); for (Widget wid : newwidgets) { panel.add(wid); } } wasHtmlContentAllowed = isHtmlContentAllowed(); wasMultiselect = isMultiselect(); } @Override protected String[] getSelectedItems() { return selectedKeys.toArray(new String[selectedKeys.size()]); } @Override public void onClick(ClickEvent event) { super.onClick(event); if (event.getSource() instanceof CheckBox) { CheckBox source = (CheckBox) event.getSource(); if (!source.isEnabled()) { // Click events on the text are received even though the // checkbox is disabled return; } if (BrowserInfo.get().isWebkit()) { // Webkit does not focus non-text input elements on click // (#11854) source.setFocus(true); } final boolean selected = source.getValue(); final String key = optionsToKeys.get(source); if (!isMultiselect()) { selectedKeys.clear(); } if (selected) { selectedKeys.add(key); } else { selectedKeys.remove(key); } client.updateVariable(paintableId, "selected", getSelectedItems(), isImmediate()); } } @Override public void setTabIndex(int tabIndex) { for (Iterator<Widget> iterator = panel.iterator(); iterator.hasNext();) { FocusWidget widget = (FocusWidget) iterator.next(); widget.setTabIndex(tabIndex); } } @Override protected void updateEnabledState() { boolean optionGroupEnabled = isEnabled() && !isReadonly(); // sets options enabled according to the widget's enabled, // readonly and each options own enabled for (Widget w : panel) { if (w instanceof HasEnabled) { HasEnabled hasEnabled = (HasEnabled) w; Boolean isOptionEnabled = optionsEnabled.get(w); if (isOptionEnabled == null) { hasEnabled.setEnabled(optionGroupEnabled); setStyleName(w.getElement(), StyleConstants.DISABLED, !isEnabled()); } else { hasEnabled.setEnabled(isOptionEnabled && optionGroupEnabled); setStyleName(w.getElement(), StyleConstants.DISABLED, !(isOptionEnabled && isEnabled())); } } } } @Override public void focus() { Iterator<Widget> iterator = panel.iterator(); if (iterator.hasNext()) { ((Focusable) iterator.next()).setFocus(true); } } @Override public void onFocus(FocusEvent arg0) { if (!blurOccured) { // no blur occured before this focus event // panel was blurred => fire the event to the server side if // requested by server side if (sendFocusEvents) { client.updateVariable(paintableId, EventId.FOCUS, "", true); } } else { // blur occured before this focus event // another control inside the panel (checkbox / radio box) was // blurred => do not fire the focus and set blurOccured to false, so // blur will not be fired, too blurOccured = false; } } @Override public void onBlur(BlurEvent arg0) { blurOccured = true; if (sendBlurEvents) { Scheduler.get().scheduleDeferred(new Command() { @Override public void execute() { // check whether blurOccured still is true and then send the // event out to the server if (blurOccured) { client.updateVariable(paintableId, EventId.BLUR, "", true); blurOccured = false; } } }); } } public boolean isHtmlContentAllowed() { return htmlContentAllowed; } public void setHtmlContentAllowed(boolean htmlContentAllowed) { this.htmlContentAllowed = htmlContentAllowed; } }