Java tutorial
/* This file is part of Cyclos. Cyclos is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Cyclos is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Cyclos; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package nl.strohalm.cyclos.mobile.client.ui; import java.util.List; import nl.strohalm.cyclos.mobile.client.Notification; import nl.strohalm.cyclos.mobile.client.ui.panels.BottomPanel; import nl.strohalm.cyclos.mobile.client.ui.panels.MenuPanel; import nl.strohalm.cyclos.mobile.client.ui.panels.TopPanel; import nl.strohalm.cyclos.mobile.client.utils.ComponentEventHelper; import nl.strohalm.cyclos.mobile.client.utils.PageAction; import nl.strohalm.cyclos.mobile.client.utils.ScreenHelper; import nl.strohalm.cyclos.mobile.client.utils.StringHelper; import com.google.gwt.event.logical.shared.AttachEvent; import com.google.gwt.event.logical.shared.ResizeEvent; import com.google.gwt.event.logical.shared.ResizeHandler; import com.google.gwt.user.client.Window; import com.google.gwt.user.client.ui.FlowPanel; import com.google.gwt.user.client.ui.Panel; import com.google.gwt.user.client.ui.ScrollPanel; import com.google.gwt.user.client.ui.SimplePanel; import com.google.gwt.user.client.ui.Widget; /** * Controls the main layout of the application. * * @author luis */ public class MainLayout { private FlowPanel topContainer; private TopPanel topPanel; private MenuPanel menuPanel; private BottomPanel bottomPanel; private ScrollPanel mainContainer; private SimplePanel notificationContainer; private SimplePanel bottomContainer; private SimplePanel menuContainer; private SimplePanel pageContainer; private FlowPanel scrollContainer; private FlowPanel mainWrapper; private Page page; private List<PageAction> actions; private Widget widget; private String pageContainerDependentStyle; private String notificationContainerDependentStyle; public MainLayout() { topPanel = new TopPanel(); menuPanel = new MenuPanel(); bottomPanel = new BottomPanel(); topContainer = new FlowPanel(); topContainer.setStyleName("top"); topContainer.add(topPanel); menuContainer = new SimplePanel(); menuContainer.setVisible(false); menuContainer.setStyleName("menu"); menuContainer.add(menuPanel); mainWrapper = new FlowPanel(); mainWrapper.setStyleName("main-wrapper"); mainContainer = new ScrollPanel(); mainContainer.setStyleName("main"); mainContainer.getElement().setId("mainContainer"); notificationContainer = new SimplePanel(); notificationContainer.setVisible(false); notificationContainer.setStyleName("notification-container"); notificationContainer.getElement().setId("notificationContainer"); pageContainer = new SimplePanel(); pageContainer.setStyleName("page"); FlowPanel container = new FlowPanel(); container.add(notificationContainer); container.add(pageContainer); mainContainer.setWidget(container); mainWrapper.add(mainContainer); bottomContainer = new SimplePanel(); bottomContainer.setStyleName("bottom"); bottomContainer.add(bottomPanel); addResizeHandler(); } /** * Adjust application layout on resize events */ private void addResizeHandler() { // Adjust layout on resize events Window.addResizeHandler(new ResizeHandler() { @Override public void onResize(ResizeEvent event) { adjust(); } }); } /** * Adjust the main container to fit exactly in available screen */ public void adjust() { int mainHeight = getMainHeight(); if (mainHeight != 0) { String height = Math.abs(mainHeight) + "px"; mainContainer.setHeight(height); } } /** * Returns the available main screen */ public int getMainHeight() { int menuHeight = 0; int bottomHeight = 0; if (page != null) { if (page.isDisplayMenu()) { menuHeight = menuContainer.getOffsetHeight(); } if (actions != null && actions.size() > 0) { bottomHeight = bottomContainer.getOffsetHeight(); } } int topHeight = topContainer.getOffsetHeight(); int totalHeight = Window.getClientHeight(); return totalHeight - topHeight - menuHeight - bottomHeight; } /** * Returns the current page */ public Page getCurrentPage() { return this.page; } /** * Adds the layout elements to the given panel */ public void apply(Panel panel) { panel.add(topContainer); panel.add(menuContainer); panel.add(mainWrapper); panel.add(bottomContainer); } /** * Shows the given page on the main layout or refresh the actual page if none given */ public void show(Page page) { if (page != null) { this.page = page; } setHeading(); setMenu(); addOptions(); addActions(); setPage(); } /** * Sets page contents in the main container */ private void setPage() { // Restores notification if the layout was changed for previous page Notification.get().resetLayout(); // Reset dependent styles if were changed for the previous page resetDependentStyles(); // Hide any visible notification Notification.get().hide(); // Create the page widget = page.initialize(); if (widget != null) { pageContainer.setWidget(widget); // Add scroll panel if native scrolling is not supported if (!page.hasCustomScroll() && !ScreenHelper.supportsTouch()) { createScrollPanel(); scrollContainer.setVisible(true); mainWrapper.add(scrollContainer); } else if (scrollContainer != null) { scrollContainer.setVisible(false); } // Adjust the page to fit in the available screen widget.addAttachHandler(new AttachEvent.Handler() { @Override public void onAttachOrDetach(AttachEvent event) { adjust(); } }); } } /** * Creates a scroll panel widget */ private void createScrollPanel() { if (scrollContainer != null) { // Scroll panel already created return; } scrollContainer = new FlowPanel(); scrollContainer.setStyleName("scroll-page"); SimplePanel up = new SimplePanel(); up.setStyleName("scroll-page-image"); up.setWidget(Icon.UP.image()); SimplePanel down = new SimplePanel(); down.setStyleName("scroll-page-image"); down.setWidget(Icon.DOWN.image()); scrollContainer.add(up); scrollContainer.add(down); // Add scrolling events ComponentEventHelper.addScrollEvents(up, down, mainContainer.getElement().getId()); } /** * Adds a custom dependent style for page container */ public void addPageContainerStyle(String style) { pageContainerDependentStyle = style; pageContainer.setStyleDependentName(style, true); } /** * Adds a custom dependent style for notification container */ public void addNotificationContainerStyle(String style) { notificationContainerDependentStyle = style; notificationContainer.setStyleDependentName(style, true); } /** * Resets added dependent styles */ public void resetDependentStyles() { if (StringHelper.isNotEmpty(pageContainerDependentStyle)) { pageContainer.setStyleDependentName(pageContainerDependentStyle, false); } if (StringHelper.isNotEmpty(notificationContainerDependentStyle)) { notificationContainer.setStyleDependentName(notificationContainerDependentStyle, false); } } /** * Sets page heading in the top menu bar */ private void setHeading() { topPanel.setHeading(page == null ? "" : page.getHeading()); } /** * Sets the menu bar, selects the given page and adjust the components to display properly */ private void setMenu() { menuContainer.setVisible(page.isDisplayMenu()); menuPanel.select(page.getPageAnchor()); } /** * Add top bar options */ private void addOptions() { if (page.getPageAnchor() != null) { topPanel.setFromPage(page.getPageAnchor()); topPanel.displayButtons(); topPanel.select(page.getPageAnchor()); } } /** * Add page actions to the bottom bar or hides the bar * if no actions are available for the given page */ private void addActions() { addActions(page.getPageActions(), false); } /** * Add actions to the bottom bar or hides the bar * if no actions are available for the given page. * Set adjust flag to true when buttons are added asynchronously * and an screen adjust is needed */ public void addActions(List<PageAction> actions, boolean adjust) { this.actions = actions; if (actions != null) { bottomContainer.setVisible(true); bottomPanel.show(); bottomPanel.setActionButtons(this.actions); } else { bottomContainer.setVisible(false); bottomPanel.hide(); bottomPanel.clearButtons(); } if (adjust) { adjust(); } } /** * Rotates load image */ public void startLoading() { topPanel.startLoading(); } /** * Stops load image rotation */ public void stopLoading() { topPanel.stopLoading(); } }