com.vaadin.flow.component.contextmenu.MenuItemsArrayGenerator Maven / Gradle / Ivy
The newest version!
/*
* Copyright 2000-2024 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.flow.component.contextmenu;
import java.io.Serializable;
import java.util.stream.Stream;
import com.vaadin.flow.component.Component;
import com.vaadin.flow.component.UI;
import com.vaadin.flow.dom.Element;
import com.vaadin.flow.function.SerializableConsumer;
/**
* A class which is utilized internally by components such as context menu and
* menu bar. It transform the components added to the menus and their sub menus
* to the hierarchical items array of the web component.
*
* @param
* the menu item type
*/
public class MenuItemsArrayGenerator>
implements Serializable {
private Component menu;
private boolean updateScheduled = false;
private final Element container;
public MenuItemsArrayGenerator(Component menu) {
this.menu = menu;
container = new Element("div");
getElement().appendVirtualChild(container);
menu.getUI().ifPresent(this::addContextMenuDependencies);
menu.addAttachListener(e -> addContextMenuDependencies(e.getUI()));
}
/**
* Rebuilds the client-side items array with the current components in the
* menu and its sub menus.
*/
public void generate() {
if (updateScheduled) {
return;
}
updateScheduled = true;
runBeforeClientResponse(ui -> {
container.removeAllChildren();
getItems().forEach(this::resetContainers);
int containerNodeId = createNewContainer(menu.getChildren());
getElement().callJsFunction("$connector.generateItems",
containerNodeId);
updateScheduled = false;
});
}
private void resetContainers(MenuItemBase menuItem) {
if (!menuItem.isParentItem()) {
menuItem.getElement().removeProperty("_containerNodeId");
return;
}
SubMenuBase subMenu = menuItem.getSubMenu();
int containerNodeId = createNewContainer(subMenu.getChildren());
menuItem.getElement().setProperty("_containerNodeId", containerNodeId);
subMenu.getItems().stream().forEach(this::resetContainers);
}
private int createNewContainer(Stream components) {
Element subContainer = new Element("div");
container.appendChild(subContainer);
components
.forEach(child -> subContainer.appendChild(child.getElement()));
return subContainer.getNode().getId();
}
private Stream getItems() {
return menu.getChildren().filter(MenuItemBase.class::isInstance)
.map(MenuItemBase.class::cast);
}
private void runBeforeClientResponse(SerializableConsumer command) {
getElement().getNode().runWhenAttached(ui -> ui
.beforeClientResponse(menu, context -> command.accept(ui)));
}
private Element getElement() {
return menu.getElement();
}
private void addContextMenuDependencies(UI ui) {
ui.getInternals().addComponentDependencies(ContextMenu.class);
}
}