Java tutorial
/******************************************************************************* * Copyright (c) 2002, 2015 Innoopract Informationssysteme GmbH and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * Innoopract Informationssysteme GmbH - initial API and implementation * EclipseSource - ongoing development ******************************************************************************/ package org.eclipse.swt.widgets; import org.eclipse.rap.rwt.internal.lifecycle.WidgetLCA; import org.eclipse.rap.rwt.internal.textsize.TextSizeUtil; import org.eclipse.rap.rwt.internal.theme.ThemeAdapter; import org.eclipse.rap.rwt.theme.BoxDimensions; import org.eclipse.swt.SWT; import org.eclipse.swt.SWTException; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.SelectionListener; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.internal.widgets.IItemHolderAdapter; import org.eclipse.swt.internal.widgets.ItemHolder; import org.eclipse.swt.internal.widgets.tabfolderkit.TabFolderLCA; import org.eclipse.swt.internal.widgets.tabfolderkit.TabFolderThemeAdapter; /** * Instances of this class implement the notebook user interface * metaphor. It allows the user to select a notebook page from * set of pages. * <p> * The item children that may be added to instances of this class * must be of type <code>TabItem</code>. * <code>Control</code> children are created and then set into a * tab item using <code>TabItem#setControl</code>. * </p><p> * Note that although this class is a subclass of <code>Composite</code>, * it does not make sense to set a layout on it. * </p><p> * <dl> * <dt><b>Styles:</b></dt> * <dd>TOP, BOTTOM</dd> * <dt><b>Events:</b></dt> * <dd>Selection</dd> * </dl> * <p> * Note: Only one of the styles TOP and BOTTOM may be specified. * </p><p> * IMPORTANT: This class is <em>not</em> intended to be subclassed. * </p> * @since 1.0 */ public class TabFolder extends Composite { private static final TabItem[] EMPTY_TAB_ITEMS = new TabItem[0]; private final ItemHolder<TabItem> itemHolder; private int selectionIndex; private final boolean onBottom; /** * Constructs a new instance of this class given its parent * and a style value describing its behavior and appearance. * <p> * The style value is either one of the style constants defined in * class <code>SWT</code> which is applicable to instances of this * class, or must be built by <em>bitwise OR</em>'ing together * (that is, using the <code>int</code> "|" operator) two or more * of those <code>SWT</code> style constants. The class description * lists the style constants that are applicable to the class. * Style bits are also inherited from superclasses. * </p> * * @param parent a composite control which will be the parent of the new instance (cannot be null) * @param style the style of control to construct * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the parent is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> * </ul> * * @see SWT * @see Widget#checkSubclass * @see Widget#getStyle */ public TabFolder(Composite parent, int style) { super(parent, checkStyle(style)); itemHolder = new ItemHolder<>(TabItem.class); selectionIndex = -1; onBottom = (super.getStyle() & SWT.BOTTOM) != 0; } @Override void initState() { removeState( /* CANVAS | */ THEME_BACKGROUND); } @Override @SuppressWarnings("unchecked") public <T> T getAdapter(Class<T> adapter) { if (adapter == IItemHolderAdapter.class) { return (T) itemHolder; } if (adapter == WidgetLCA.class) { return (T) TabFolderLCA.INSTANCE; } return super.getAdapter(adapter); } ////////////////// // Item management /** * Returns an array of <code>TabItem</code>s which are the items * in the receiver. * <p> * Note: This is not the actual structure used by the receiver * to maintain its list of items, so modifying the array will * not affect the receiver. * </p> * * @return the items in the receiver * * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public TabItem[] getItems() { checkWidget(); return itemHolder.getItems(); } /** * Returns the item at the given, zero-relative index in the * receiver. Throws an exception if the index is out of range. * * @param index the index of the item to return * @return the item at the given index * * @exception IllegalArgumentException <ul> * <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public TabItem getItem(int index) { checkWidget(); return itemHolder.getItem(index); } /** * Returns the tab item at the given point in the receiver * or null if no such item exists. The point is in the * coordinate system of the receiver. * * @param point the point used to locate the item * @return the tab item at the given point, or null if the point is not in a tab item * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the point is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> * * @since 1.3 */ public TabItem getItem(Point point) { checkWidget(); if (point == null) { error(SWT.ERROR_NULL_ARGUMENT); } TabItem result = null; for (int i = 0; i < getItemCount() && result == null; i++) { TabItem item = getItem(i); Rectangle itemBounds = item.getBounds(); if (itemBounds.contains(point)) { result = item; } } return result; } /** * Returns the number of items contained in the receiver. * * @return the number of items * * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public int getItemCount() { checkWidget(); return itemHolder.size(); } /** * Searches the receiver's list starting at the first item * (index 0) until an item is found that is equal to the * argument, and returns the index of that item. If no item * is found, returns -1. * * @param item the search item * @return the index of the item * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the string is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public int indexOf(TabItem item) { checkWidget(); if (item == null) { SWT.error(SWT.ERROR_NULL_ARGUMENT); } if (item.isDisposed()) { SWT.error(SWT.ERROR_INVALID_ARGUMENT); } return itemHolder.indexOf(item); } ///////////////////// // Seletion handling /** * Returns an array of <code>TabItem</code>s that are currently * selected in the receiver. An empty array indicates that no * items are selected. * <p> * Note: This is not the actual structure used by the receiver * to maintain its selection, so modifying the array will * not affect the receiver. * </p> * @return an array representing the selection * * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public TabItem[] getSelection() { checkWidget(); TabItem[] result = EMPTY_TAB_ITEMS; if (getSelectionIndex() != -1) { TabItem selected = itemHolder.getItem(getSelectionIndex()); result = new TabItem[] { selected }; } return result; } /** * Sets the receiver's selection to the given item. * The current selected is first cleared, then the new item is * selected. * * @param item the item to select * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the item is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public void setSelection(TabItem item) { checkWidget(); if (item == null) { error(SWT.ERROR_NULL_ARGUMENT); } setSelection(new TabItem[] { item }); } /** * Sets the receiver's selection to be the given array of items. * The current selected is first cleared, then the new items are * selected. * * @param items the array of items * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the items array is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public void setSelection(TabItem[] items) { checkWidget(); if (items == null) { error(SWT.ERROR_NULL_ARGUMENT); } if (items.length == 0) { setSelection(-1, false); } else { for (int i = items.length - 1; i >= 0; --i) { int index = indexOf(items[i]); if (index != -1) { setSelection(index, false); } } } } /** * Selects the item at the given zero-relative index in the receiver. * If the item at the index was already selected, it remains selected. * The current selection is first cleared, then the new items are * selected. Indices that are out of range are ignored. * * @param index the index of the item to select * * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public void setSelection(int index) { checkWidget(); if (index >= 0 && index < itemHolder.size()) { setSelection(index, false); } } /** * Returns the zero-relative index of the item which is currently * selected in the receiver, or -1 if no item is selected. * * @return the index of the selected item * * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public int getSelectionIndex() { checkWidget(); if (selectionIndex >= itemHolder.size()) { selectionIndex = itemHolder.size() - 1; } return selectionIndex; } /////////////////////////////// // Layout and size computations @Override public void layout() { checkWidget(); Control[] children = getChildren(); for (int i = 0; i < children.length; i++) { children[i].setBounds(getClientArea()); } } @Override public Rectangle getClientArea() { checkWidget(); Rectangle bounds = getBounds(); BoxDimensions border = getBorder(); int borderWidth = border.left + border.right; int borderHeight = border.top + border.bottom; BoxDimensions containerBorder = getContentContainerBorder(); int containerBorderWidth = containerBorder.left + containerBorder.right; int containerBorderHeight = containerBorder.top + containerBorder.bottom; int tabBarHeight = getTabBarHeight(); int x = border.left + containerBorder.left; int y = border.top + containerBorder.top + (onBottom ? 0 : tabBarHeight); int width = bounds.width - borderWidth - containerBorderWidth; int height = bounds.height - tabBarHeight - borderHeight - containerBorderHeight; return new Rectangle(x, y, width, height); } @Override public Rectangle computeTrim(int x, int y, int width, int height) { checkWidget(); BoxDimensions border = getBorder(); int borderWidth = border.left + border.right; int borderHeight = border.top + border.bottom; BoxDimensions containerBorder = getContentContainerBorder(); int containerBorderWidth = containerBorder.left + containerBorder.right; int containerBorderHeight = containerBorder.top + containerBorder.bottom; int tabBarHeight = getTabBarHeight(); int trimX = x - border.left - containerBorder.left; int trimY = y - border.top - containerBorder.top - (onBottom ? 0 : tabBarHeight); int trimWidth = width + borderWidth + containerBorderWidth; int trimHeight = height + borderHeight + containerBorderHeight + tabBarHeight; return new Rectangle(trimX, trimY, trimWidth, trimHeight); } @Override public Point computeSize(int wHint, int hHint, boolean changed) { checkWidget(); Point itemsSize = new Point(0, 0); Point contentsSize = new Point(0, 0); TabItem[] items = getItems(); // TODO: one item should be enough since layout already includes all items for (int i = 0; i < items.length; i++) { Rectangle thisItemBounds = items[i].getBounds(); itemsSize.x += thisItemBounds.width; itemsSize.y = Math.max(itemsSize.y, thisItemBounds.height); Control control = items[i].getControl(); if (control != null) { Point thisSize = control.computeSize(SWT.DEFAULT, SWT.DEFAULT); contentsSize.x = Math.max(contentsSize.x, thisSize.x); contentsSize.y = Math.max(contentsSize.y, thisSize.y); } } int width = Math.max(itemsSize.x, contentsSize.x); int height = itemsSize.y + contentsSize.y; if (width == 0) { width = DEFAULT_WIDTH; } if (height == 0) { height = DEFAULT_HEIGHT; } if (wHint != SWT.DEFAULT) { width = wHint; } if (hHint != SWT.DEFAULT) { height = hHint; } BoxDimensions border = getBorder(); width += border.left + border.right; height += border.top + border.bottom; return new Point(width, height); } /////////////////////////////////////// // Listener registration/deregistration /** * Adds the listener to the collection of listeners who will * be notified when the receiver's selection changes, by sending * it one of the messages defined in the <code>SelectionListener</code> * interface. * <p> * When <code>widgetSelected</code> is called, the item field of the event object is valid. * <code>widgetDefaultSelected</code> is not called. * </p> * * @param listener the listener which should be notified * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> * * @see SelectionListener * @see #removeSelectionListener * @see SelectionEvent */ public void addSelectionListener(SelectionListener listener) { checkWidget(); if (listener == null) { SWT.error(SWT.ERROR_NULL_ARGUMENT); } TypedListener typedListener = new TypedListener(listener); addListener(SWT.Selection, typedListener); addListener(SWT.DefaultSelection, typedListener); } /** * Removes the listener from the collection of listeners who will * be notified when the receiver's selection changes. * * @param listener the listener which should no longer be notified * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> * * @see SelectionListener * @see #addSelectionListener */ public void removeSelectionListener(SelectionListener listener) { checkWidget(); if (listener == null) { SWT.error(SWT.ERROR_NULL_ARGUMENT); } removeListener(SWT.Selection, listener); removeListener(SWT.DefaultSelection, listener); } @Override void releaseChildren() { TabItem[] items = getItems(); for (int i = 0; i < items.length; i++) { items[i].dispose(); } super.releaseChildren(); } void createItem(TabItem item, int index) { itemHolder.insert(item, index); if (getItemCount() == 1) { setSelection(0, true); } else if (index <= selectionIndex) { setSelection(selectionIndex + 1, false); } } void destroyItem(TabItem item) { int index = itemHolder.indexOf(item); int oldSelectionIndex = getSelectionIndex(); if (index == oldSelectionIndex) { setSelection(-1, false); } itemHolder.remove(item); if (itemHolder.size() > 0 && index <= oldSelectionIndex && !isInDispose()) { boolean notifySelectionChanged = index == oldSelectionIndex; setSelection(Math.max(0, oldSelectionIndex - 1), notifySelectionChanged); } } @Override void notifyResize(Point oldSize) { super.notifyResize(oldSize); updateSelectedItemControl(); } private void updateSelectedItemControl() { int index = getSelectionIndex(); if (index != -1) { Control control = getItem(index).getControl(); if (control != null && !control.isDisposed()) { control.setBounds(getClientArea()); control.setVisible(true); } } } private void setSelection(int index, boolean notify) { int oldIndex = getSelectionIndex(); if (oldIndex != index) { if (oldIndex != -1) { TabItem item = itemHolder.getItem(oldIndex); Control control = item.getControl(); if (control != null && !control.isDisposed()) { control.setVisible(false); } } selectionIndex = index; if (index != -1) { updateSelectedItemControl(); if (notify) { Event event = new Event(); event.item = itemHolder.getItem(index); notifyListeners(SWT.Selection, event); } } } } private static int checkStyle(int style) { int result = checkBits(style, SWT.TOP, SWT.BOTTOM, 0, 0, 0, 0); /* * Even though it is legal to create this widget * with scroll bars, they serve no useful purpose * because they do not automatically scroll the * widget's client area. The fix is to clear * the SWT style. */ return result & ~(SWT.H_SCROLL | SWT.V_SCROLL); } private BoxDimensions getContentContainerBorder() { return getThemeAdapter().getContentContainerBorder(this); } private int getTabBarHeight() { int result = 0; TabFolderThemeAdapter themeAdapter = getThemeAdapter(); int textHeight = TextSizeUtil.getCharHeight(getFont()); for (TabItem item : getItems()) { Image image = item.getImage(); int imageHeight = image == null ? 0 : image.getBounds().height; BoxDimensions itemPadding = themeAdapter.getItemPadding(item); int paddingHeight = itemPadding.top + itemPadding.bottom; BoxDimensions itemMargin = themeAdapter.getItemMargin(item); int marginHeight = itemMargin.top + itemMargin.bottom; BoxDimensions itemBorder = themeAdapter.getItemBorder(item); int borderHeight = itemBorder.top + itemBorder.bottom; int itemHeight = Math.max(textHeight, imageHeight) + paddingHeight + marginHeight + borderHeight; result = Math.max(result, itemHeight); } return result; } TabFolderThemeAdapter getThemeAdapter() { return (TabFolderThemeAdapter) getAdapter(ThemeAdapter.class); } @Override void reskinChildren(int flags) { TabItem[] items = getItems(); if (items != null) { for (int i = 0; i < items.length; i++) { TabItem item = items[i]; if (item != null) { item.reskin(flags); } } } super.reskinChildren(flags); } }