org.eclipse.swt.widgets.ToolBar.java Source code

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/*******************************************************************************
 * 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.theme.ThemeAdapter;
import org.eclipse.rap.rwt.theme.BoxDimensions;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.graphics.Font;
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.toolbarkit.ToolBarLCA;
import org.eclipse.swt.internal.widgets.toolbarkit.ToolBarThemeAdapter;

/**
 * Instances of this class support the layout of selectable
 * tool bar items.
 * <p>
 * The item children that may be added to instances of this class
 * must be of type <code>ToolItem</code>.
 * </p><p>
 * Note that although this class is a subclass of <code>Composite</code>,
 * it does not make sense to add <code>Control</code> children to it,
 * or set a layout on it.
 * </p><p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>FLAT, <!-- WRAP, --> RIGHT, HORIZONTAL, VERTICAL<!--, SHADOW_OUT--></dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * Note: Only one of the styles HORIZONTAL and VERTICAL may be specified.
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 * @since 1.0
 */
public class ToolBar extends Composite {

    private static final int DEFAULT_TOOLBAR_WIDTH = 24;
    private static final int DEFAULT_TOOLBAR_HEIGHT = 22;

    private final ItemHolder<ToolItem> itemHolder;

    /**
     * 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#FLAT
     *<!-- @see SWT#WRAP -->
     *<!-- @see SWT#RIGHT -->
     * @see SWT#HORIZONTAL
     *<!-- @see SWT#SHADOW_OUT -->
     * @see SWT#VERTICAL
     * <!--@see Widget#checkSubclass()-->
     * @see Widget#getStyle()
     */
    public ToolBar(Composite parent, int style) {
        super(parent, checkStyle(style));
        /*
         * Ensure that either of HORIZONTAL or VERTICAL is set. NOTE: HORIZONTAL and
         * VERTICAL have the same values as H_SCROLL and V_SCROLL so it is necessary
         * to first clear these bits to avoid scroll bars and then reset the bits
         * using the original style supplied by the programmer.
         */
        if ((style & SWT.VERTICAL) != 0) {
            this.style |= SWT.VERTICAL;
        } else {
            this.style |= SWT.HORIZONTAL;
        }
        itemHolder = new ItemHolder<>(ToolItem.class);
    }

    @Override
    @SuppressWarnings("unchecked")
    public <T> T getAdapter(Class<T> adapter) {
        if (adapter == IItemHolderAdapter.class) {
            return (T) itemHolder;
        }
        if (adapter == WidgetLCA.class) {
            return (T) ToolBarLCA.INSTANCE;
        }
        return super.getAdapter(adapter);
    }

    //////////////////
    // Item management

    /**
     * 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 ToolItem getItem(int index) {
        checkWidget();
        return itemHolder.getItem(index);
    }

    /**
     * Returns the 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 item at the given point
     *
     * @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 ToolItem getItem(Point point) {
        checkWidget();
        if (point == null) {
            error(SWT.ERROR_NULL_ARGUMENT);
        }
        ToolItem result = null;
        ToolItem[] items = getItems();
        for (int i = 0; result == null && i < items.length; i++) {
            Rectangle rect = items[i].getBounds();
            if (rect.contains(point)) {
                result = items[i];
            }
        }
        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();
    }

    /**
     * Returns an array of <code>ToolItem</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 ToolItem[] getItems() {
        checkWidget();
        return itemHolder.getItems();
    }

    /**
     * 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 tool item is null</li>
     *    <li>ERROR_INVALID_ARGUMENT - if the tool item has been disposed</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(ToolItem item) {
        checkWidget();
        if (item == null) {
            SWT.error(SWT.ERROR_NULL_ARGUMENT);
        }
        if (item.isDisposed()) {
            SWT.error(SWT.ERROR_INVALID_ARGUMENT);
        }
        return itemHolder.indexOf(item);
    }

    ////////////////////
    // Size computations

    @Override
    public Point computeSize(int wHint, int hHint, boolean changed) {
        checkWidget();
        int width = 0;
        int height = 0;
        if ((style & SWT.VERTICAL) != 0) {
            for (int i = 0; i < itemHolder.size(); i++) {
                ToolItem item = itemHolder.getItem(i);
                Rectangle itemBounds = item.getBounds();
                width = Math.max(width, itemBounds.width);
                if (i == itemHolder.size() - 1) {
                    height += itemBounds.height + itemBounds.y;
                }
            }
        } else {
            for (int i = 0; i < itemHolder.size(); i++) {
                ToolItem item = itemHolder.getItem(i);
                Rectangle itemBounds = item.getBounds();
                height = Math.max(height, itemBounds.height);
                if (i == itemHolder.size() - 1) {
                    width += itemBounds.width + itemBounds.x;
                }

            }
        }
        BoxDimensions toolBarPadding = getToolBarPadding();
        width += toolBarPadding.left + toolBarPadding.right;
        height += toolBarPadding.top + toolBarPadding.bottom;
        if (width == 0) {
            width = DEFAULT_TOOLBAR_WIDTH;
        }
        if (height == 0) {
            height = DEFAULT_TOOLBAR_HEIGHT;
        }
        if (wHint != SWT.DEFAULT) {
            width = wHint;
        }
        if (hHint != SWT.DEFAULT) {
            height = hHint;
        }
        for (int i = 0; i < itemHolder.size(); i++) {
            ToolItem item = itemHolder.getItem(i);
            item.resizeControl();
        }
        Rectangle trim = computeTrim(0, 0, width, height);
        width = trim.width;
        height = trim.height;
        return new Point(width, height);
    }

    BoxDimensions getToolBarPadding() {
        ToolBarThemeAdapter themeAdapter = (ToolBarThemeAdapter) getAdapter(ThemeAdapter.class);
        return themeAdapter.getToolBarPadding(this);
    }

    /**
     * Returns the number of rows in the receiver. When
     * the receiver has the <code>WRAP</code> style, the
     * number of rows can be greater than one.  Otherwise,
     * the number of rows is always one.
     *
     * @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 getRowCount() {
        checkWidget();
        // return 1 as long as we don't support the WRAP style bit
        return 1;
    }

    @Override
    public void setBounds(Rectangle bounds) {
        Point oldSize = getSize();
        super.setBounds(bounds);
        if (!oldSize.equals(getSize())) {
            layoutItems();
        }
    }

    @Override
    public void setFont(Font font) {
        super.setFont(font);
        layoutItems();
    }

    ////////////////////////
    // Child control removal

    @Override
    void removeChild(Control control) {
        super.removeChild(control);
        ToolItem[] items = itemHolder.getItems();
        for (int i = 0; i < items.length; i++) {
            ToolItem item = items[i];
            if (item != null && item.getControl() == control) {
                item.setControl(null);
            }
        }
    }

    ////////////////////
    // Widget overrides

    @Override
    final void releaseChildren() {
        ToolItem[] toolItems = itemHolder.getItems();
        for (int i = 0; i < toolItems.length; i++) {
            toolItems[i].dispose();
        }
    }

    //////////////////
    // Helping methods

    private static int checkStyle(int style) {
        /*
        * 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 style & ~(SWT.H_SCROLL | SWT.V_SCROLL);
    }

    void createItem(ToolItem item, int index) {
        itemHolder.insert(item, index);
        layoutItems();
    }

    void destroyItem(ToolItem item) {
        itemHolder.remove(item);
        layoutItems();
    }

    void layoutItems() {
        for (int i = 0; i < itemHolder.size(); i++) {
            ToolItem item = itemHolder.getItem(i);
            Rectangle ibounds = item.getBounds();
            Rectangle bounds = getBounds();
            boolean hasEnoughWidth = ibounds.x + ibounds.width <= bounds.width;
            boolean hasEnoughHeight = ibounds.y + ibounds.height <= bounds.height;
            item.setVisible(hasEnoughWidth && hasEnoughHeight);
            item.resizeControl();
        }
    }

    ///////////////////
    // Skinning support

    @Override
    void reskinChildren(int flags) {
        ToolItem[] items = getItems();
        if (items != null) {
            for (int i = 0; i < items.length; i++) {
                ToolItem item = items[i];
                if (item != null) {
                    item.reskin(flags);
                }
            }
        }
        super.reskinChildren(flags);
    }

}