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 static org.eclipse.swt.internal.widgets.MarkupUtil.isToolTipMarkupEnabledFor; import static org.eclipse.swt.internal.widgets.MarkupValidator.isValidationDisabledFor; import org.eclipse.rap.rwt.RWT; import org.eclipse.rap.rwt.internal.lifecycle.WidgetLCA; import org.eclipse.rap.rwt.internal.textsize.TextSizeUtil; import org.eclipse.rap.rwt.theme.BoxDimensions; import org.eclipse.swt.SWT; import org.eclipse.swt.SWTException; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.internal.widgets.MarkupValidator; import org.eclipse.swt.internal.widgets.tabfolderkit.TabFolderThemeAdapter; import org.eclipse.swt.internal.widgets.tabitemkit.TabItemLCA; /** * Instances of this class represent a selectable user interface object * corresponding to a tab for a page in a tab folder. * <dl> * <dt><b>Styles:</b></dt> * <dd>(none)</dd> * <dt><b>Events:</b></dt> * <dd>(none)</dd> * </dl> * <p> * IMPORTANT: This class is <em>not</em> intended to be subclassed. * </p> */ public class TabItem extends Item { // [if] This constants must be kept in sync with AppearancesBase.js private final static int TABS_SPACING = 1; private final static int IMAGE_TEXT_SPACING = 4; private final TabFolder parent; private Control control; private String toolTipText; /** * Constructs a new instance of this class given its parent * (which must be a <code>TabFolder</code>) and a style value * describing its behavior and appearance. The item is added * to the end of the items maintained by its parent. * <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 TabItem(TabFolder parent, int style) { super(parent, checkStyle(style)); this.parent = parent; parent.createItem(this, parent.getItemCount()); } /** * Constructs a new instance of this class given its parent * (which must be a <code>TabFolder</code>), a style value * describing its behavior and appearance, and the index * at which to place it in the items maintained by its parent. * <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 * @param index the zero-relative index to store the receiver in its parent * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the parent is null</li> * <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)</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 TabItem(TabFolder parent, int style, int index) { super(parent, checkStyle(style)); this.parent = parent; parent.createItem(this, index); } /** * Returns the receiver's parent, which must be a <code>TabFolder</code>. * * @return the receiver's parent * * @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 TabFolder getParent() { checkWidget(); return parent; } /** * Returns the control that is used to fill the client area of * the tab folder when the user selects the tab item. If no * control has been set, return <code>null</code>. * <p> * @return the control * * @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 Control getControl() { checkWidget(); return control; } /** * Sets the control that is used to fill the client area of * the tab folder when the user selects the tab item. * <p> * @param control the new control (or null) * * @exception IllegalArgumentException <ul> * <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</li> * <li>ERROR_INVALID_PARENT - if the control is not in the same widget tree</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 setControl(Control control) { checkWidget(); if (control != null) { if (control.isDisposed()) { error(SWT.ERROR_INVALID_ARGUMENT); } if (control._getParent() != parent) { error(SWT.ERROR_INVALID_PARENT); } } if (this.control != null && this.control.isDisposed()) { this.control = null; } Control oldControl = this.control; Control newControl = control; this.control = control; int index = parent.indexOf(this); if (index != parent.getSelectionIndex()) { if (newControl != null) { newControl.setVisible(false); } } else { if (newControl != null) { newControl.setBounds(parent.getClientArea()); newControl.setVisible(true); } if (oldControl != null) { oldControl.setVisible(false); } } } /** * Returns a rectangle describing the receiver's size and location * relative to its parent. * * @return the receiver's bounding rectangle * * @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 Rectangle getBounds() { checkWidget(); Rectangle result = new Rectangle(0, 0, 0, 0); int index = parent.indexOf(this); if (index != -1) { String text = getText(); if (text != null) { Point extent = TextSizeUtil.stringExtent(parent.getFont(), text); result.width = extent.x; result.height = extent.y; } Image image = getImage(); if (image != null) { Rectangle imageSize = image.getBounds(); result.width += imageSize.width + IMAGE_TEXT_SPACING; result.height = Math.max(result.height, imageSize.height); } TabFolderThemeAdapter themeAdapter = parent.getThemeAdapter(); BoxDimensions padding = themeAdapter.getItemPadding(this); BoxDimensions margin = themeAdapter.getItemMargin(this); BoxDimensions itemBorder = themeAdapter.getItemBorder(this); result.width += itemBorder.left + itemBorder.right + padding.left + padding.right; result.height += itemBorder.top + itemBorder.bottom + padding.top + padding.bottom; if (isBarTop()) { result.y = margin.top; } else { BoxDimensions border = parent.getBorder(); result.y = parent.getBounds().height - (border.top + border.bottom) - result.height; result.y -= margin.bottom; } if (index > 0) { TabItem prevItem = parent.getItem(index - 1); Rectangle prevItemBounds = prevItem.getBounds(); int selectionIndex = parent.getSelectionIndex(); result.x = prevItemBounds.x + prevItemBounds.width + TABS_SPACING; if (index == selectionIndex || index - 1 == selectionIndex) { result.x -= TABS_SPACING; } } } return result; } private boolean isBarTop() { return (parent.getStyle() & SWT.BOTTOM) == 0; } @Override public void setImage(Image image) { checkWidget(); int index = parent.indexOf(this); if (index > -1) { super.setImage(image); } } /** * Sets the receiver's tool tip text to the argument, which * may be null indicating that no tool tip text should be shown. * * @param toolTipText the new tool tip text (or null) * * @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 1.2 */ public void setToolTipText(String toolTipText) { checkWidget(); if (toolTipText != null && isToolTipMarkupEnabledFor(this) && !isValidationDisabledFor(this)) { MarkupValidator.getInstance().validate(toolTipText); } this.toolTipText = toolTipText; } /** * Returns the receiver's tool tip text, or null if it has * not been set. * * @return the receiver's tool tip text * * @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 1.2 */ public String getToolTipText() { checkWidget(); return toolTipText; } @Override public void setData(String key, Object value) { handleBadge(key, value); if (!RWT.TOOLTIP_MARKUP_ENABLED.equals(key) || !isToolTipMarkupEnabledFor(this)) { super.setData(key, value); } } @Override @SuppressWarnings("unchecked") public <T> T getAdapter(Class<T> adapter) { if (adapter == WidgetLCA.class) { return (T) TabItemLCA.INSTANCE; } return super.getAdapter(adapter); } private void handleBadge(String key, Object value) { if (RWT.BADGE.equals(key) && value != null && !(value instanceof String)) { error(SWT.ERROR_INVALID_ARGUMENT); } } /////////////////////////////////// // Methods to dispose of the widget @Override void releaseParent() { super.releaseParent(); parent.destroyItem(this); } ////////////////// // Helping methods private static int checkStyle(int style) { int result = SWT.NONE; if (style > 0) { result = style; } return result; } }