tabletreeitem.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.custom;


import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;

/**
 * A TableTreeItem is a selectable user interface object
 * that represents an item in a heirarchy of items in a
 * TableTree.
 */
public class TableTreeItem extends Item {
	TableItem tableItem;
	TableTree parent;
	TableTreeItem parentItem;
	TableTreeItem [] items = TableTree.EMPTY_ITEMS;
	String[] texts = TableTree.EMPTY_TEXTS;
	Image[] images = TableTree.EMPTY_IMAGES;
	Color background;
	Color foreground;
	Font font;
	boolean expanded;
	boolean checked;
	boolean grayed;

/**
 * Constructs a new instance of this class given its parent
 * (which must be a <code>TableTree</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>
 * </ul>
 *
 * @see SWT
 * @see Widget#getStyle()
 */
public TableTreeItem(TableTree parent, int style) {
	this (parent, style, parent.getItemCount());
}

/**
 * Constructs a new instance of this class given its parent
 * (which must be a <code>TableTree</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 index to store the receiver in its parent
 *
 * @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>
 * </ul>
 *
 * @see SWT
 * @see Widget#getStyle()
 */
public TableTreeItem(TableTree parent, int style, int index) {
	this (parent, null, style, index);
}

/**
 * Constructs a new instance of this class given its parent
 * (which must be a <code>TableTreeItem</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>
 * </ul>
 *
 * @see SWT
 * @see Widget#getStyle()
 */
public TableTreeItem(TableTreeItem parent, int style) {
	this (parent, style, parent.getItemCount());
}

/**
 * Constructs a new instance of this class given its parent
 * (which must be a <code>TableTreeItem</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 index to store the receiver in its parent
 *
 * @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>
 * </ul>
 *
 * @see SWT
 * @see Widget#getStyle()
 */
public TableTreeItem(TableTreeItem parent, int style, int index) {
	this (parent.getParent(), parent, style, index);
}

TableTreeItem(TableTree parent, TableTreeItem parentItem, int style, int index) {
	super(parent, style);
	this.parent = parent;
	this.parentItem = parentItem;
	if (parentItem == null) {
		
		/* Root items are visible immediately */
		int tableIndex = parent.addItem(this, index);
		tableItem = new TableItem(parent.getTable(), style, tableIndex);
		tableItem.setData(TableTree.ITEMID, this);
		addCheck();
		/*
		* Feature in the Table.  The table uses the first image that
		* is inserted into the table to size the table rows.  If the
		* user is allowed to insert the first image, this will cause
		* the +/- images to be scaled.  The fix is to insert a dummy
		* image to force the size.
		*/
		if (parent.sizeImage == null) {
			int itemHeight = parent.getItemHeight();
			parent.sizeImage = new Image(null, itemHeight, itemHeight);
			GC gc = new GC (parent.sizeImage);
			gc.setBackground(parent.getBackground());
			gc.fillRectangle(0, 0, itemHeight, itemHeight);
			gc.dispose();
			tableItem.setImage(0, parent.sizeImage);
		}
	} else {
		parentItem.addItem(this, index);
	}
}
void addCheck() {
	Table table = parent.getTable();
	if ((table.getStyle() & SWT.CHECK) == 0) return;
	tableItem.setChecked(checked);
	tableItem.setGrayed(grayed);
}
void addItem(TableTreeItem item, int index) {
	if (item == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (index < 0 || index > items.length) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
		
	/* Now that item has a sub-node it must indicate that it can be expanded */
	if (items.length == 0 && index == 0) {
		if (tableItem != null) {
			Image image = expanded ? parent.getMinusImage() : parent.getPlusImage();
			tableItem.setImage(0, image);
		}
	}
	
	/* Put the item in the items list */
	TableTreeItem[] newItems = new TableTreeItem[items.length + 1];
	System.arraycopy(items, 0, newItems, 0, index);
	newItems[index] = item;
	System.arraycopy(items, index, newItems, index + 1, items.length - index);
	items = newItems;
	if (expanded) item.setVisible(true);
}

/**
 * Returns the receiver's background color.
 *
 * @return the background color
 * 
 * @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 2.0
 * 
 */
public Color getBackground () {
	checkWidget ();
	return (background == null) ? parent.getBackground() : background;
}

/**
 * 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>
 */
public Rectangle getBounds (int index) {
	checkWidget();
	if (tableItem != null) {
		return tableItem.getBounds(index);
	} else {
		return new Rectangle(0, 0, 0, 0);
	}
}
/**
 * Returns <code>true</code> if the receiver is checked,
 * and false otherwise.  When the parent does not have
 * the <code>CHECK style, return false.
 *
 * @return the checked state of the checkbox
 *
 * @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 boolean getChecked () {
	checkWidget();
	if (tableItem == null) return checked;
	return tableItem.getChecked();
}

/**
 * Returns <code>true</code> if the receiver is grayed,
 * and false otherwise. When the parent does not have
 * the <code>CHECK</code> style, return false.
 *
 * @return the grayed state of the checkbox
 *
 * @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 2.1
 */
public boolean getGrayed () {
	checkWidget();
	if (tableItem == null) return grayed;
	return tableItem.getGrayed();
}

/**
 * Returns <code>true</code> if the receiver is expanded,
 * and false otherwise.
 * <p>
 *
 * @return the expanded state
 */
public boolean getExpanded () {
	//checkWidget();
	return expanded;
}

/**
 * Returns the font that the receiver will use to paint textual information for this item.
 *
 * @return the receiver's font
 *
 * @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 3.0
 */
public Font getFont () {
	checkWidget ();
	return (font == null) ? parent.getFont() : font;
}
/**
 * Returns the foreground color that the receiver will use to draw.
 *
 * @return the receiver's foreground color
 *
 * @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 2.0
 * 
 */
public Color getForeground () {
	checkWidget ();
	return (foreground == null) ? parent.getForeground() : foreground;
}
/**
 * Gets the first image.
 * <p>
 * The image in column 0 is reserved for the [+] and [-]
 * images of the tree, therefore getImage(0) will return null.
 *
 * @return the image at index 0
 * 
 * @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 Image getImage () {
	checkWidget();
	return getImage(0);
}

/**
 * Gets the image at the specified index.
 * <p>
 * Indexing is zero based. The image can be null.
 * The image in column 0 is reserved for the [+] and [-]
 * images of the tree, therefore getImage(0) will return null.
 * Return null if the index is out of range.
 *
 * @param index the index of the image
 * @return the image at the specified index or null
 */
public Image getImage (int index) {
	//checkWidget();
	if (0 < index && index < images.length) return images[index];
	return null;
}

int getIndent() {
	if (parentItem == null) return 0;
	return parentItem.getIndent() + 1;
}

/**
 * Returns the number of items contained in the receiver
 * that are direct item children of the receiver.
 *
 * @return the number of items
 */
public int getItemCount () {
	//checkWidget();
	return items.length;
}

/**
 * Returns an array of <code>TableTreeItem</code>s which are the
 * direct item children of 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 receiver's items
 */
public TableTreeItem[] getItems () {
	//checkWidget();
	TableTreeItem[] newItems = new TableTreeItem[items.length];
	System.arraycopy(items, 0, newItems, 0, items.length);
	return newItems;
}

TableTreeItem getItem(TableItem tableItem) {
	if (tableItem == null) return null;
	if (this.tableItem == tableItem) return this;
	for (int i = 0; i < items.length; i++) {
		TableTreeItem item =  items[i].getItem(tableItem);
	    	if (item != null) return item;
	}
	return null;
}

/**
 * Returns the receiver's parent, which must be a <code>TableTree</code>.