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; import com.google.gwt.dom.client.Element; import com.google.gwt.user.client.ui.Widget; import com.vaadin.shared.AbstractComponentState; /** * An interface used by client-side widgets or paintable parts to receive * updates from the corresponding server-side components in the form of * {@link UIDL}. * * Updates can be sent back to the server using the * {@link ApplicationConnection#updateVariable()} methods. */ public interface ComponentConnector extends HasWidget { /* * (non-Javadoc) * * @see com.vaadin.client.VPaintable#getState() */ @Override public AbstractComponentState getState(); public LayoutManager getLayoutManager(); /** * Returns <code>true</code> if the width of this paintable is currently * undefined. If the width is undefined, the actual width of the paintable * is defined by its contents. * * @return <code>true</code> if the width is undefined, else * <code>false</code> */ public boolean isUndefinedWidth(); /** * Returns <code>true</code> if the height of this paintable is currently * undefined. If the height is undefined, the actual height of the paintable * is defined by its contents. * * @return <code>true</code> if the height is undefined, else * <code>false</code> */ public boolean isUndefinedHeight(); /** * Returns <code>true</code> if the width of this paintable is currently * relative. If the width is relative, the actual width of the paintable is * a percentage of the size allocated to it by its parent. * * @return <code>true</code> if the width is undefined, else * <code>false</code> */ public boolean isRelativeWidth(); /** * Returns <code>true</code> if the height of this paintable is currently * relative. If the height is relative, the actual height of the paintable * is a percentage of the size allocated to it by its parent. * * @return <code>true</code> if the width is undefined, else * <code>false</code> */ public boolean isRelativeHeight(); /** * Return true if parent handles caption, false if the paintable handles the * caption itself. * * <p> * This should always return true and all components should let the parent * handle the caption and use other attributes for internal texts in the * component * </p> * * @return true if caption handling is delegated to the parent, false if * parent should not be allowed to render caption */ public boolean delegateCaptionHandling(); /** * Sets the enabled state of the widget associated to this connector. * * @param widgetEnabled * true if the widget should be enabled, false otherwise */ public void setWidgetEnabled(boolean widgetEnabled); /** * Gets the tooltip info for the given element. * <p> * When overriding this method, {@link #hasTooltip()} should also be * overridden to return <code>true</code> in all situations where this * method might return a non-empty result. * </p> * * @param element * The element to lookup a tooltip for * @return The tooltip for the element or null if no tooltip is defined for * this element. */ public TooltipInfo getTooltipInfo(Element element); /** * Check whether there might be a tooltip for this component. The framework * will only add event listeners for automatically handling tooltips (using * {@link #getTooltipInfo(Element)}) if this method returns true. * <p> * This is only done to optimize performance, so in cases where the status * is not known, it's safer to return <code>true</code> so that there will * be a tooltip handler even though it might not be needed in all cases. * * @return <code>true</code> if some part of the component might have a * tooltip, otherwise <code>false</code> */ public boolean hasTooltip(); /** * Called for the active (focused) connector when a situation occurs that * the focused connector might have buffered changes which need to be * processed before other activity takes place. * <p> * This is currently called when the user changes the fragment using the * back/forward button in the browser and allows the focused field to submit * its value to the server before the fragment change event takes place. * </p> */ public void flush(); }