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Standard Widget Toolkit for GTK on ppc64le
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/*******************************************************************************
 * Copyright (c) 2000, 2018 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.widgets;


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

/**
 * Instances of this class are selectable user interface
 * objects that represent the dynamically positionable
 * areas of a CoolBar.
 * 
 * Styles:
 * DROP_DOWN
 * Events:
 * Selection
 * 
 * 
 * IMPORTANT: This class is not intended to be subclassed.
 * 
 *
 * @see Sample code and further information
 * @noextend This class is not intended to be subclassed by clients.
 */
public class CoolItem extends Item {
	Control control;
	CoolBar parent;
	boolean ideal;
	int preferredWidth, preferredHeight, minimumWidth, minimumHeight, requestedWidth;
	Rectangle itemBounds = new Rectangle(0, 0, 0, 0);

	static final int MARGIN_WIDTH = 4;
	static final int GRABBER_WIDTH = 2;
	static final int MINIMUM_WIDTH = (2 * MARGIN_WIDTH) + GRABBER_WIDTH;

	private int CHEVRON_HORIZONTAL_TRIM = -1;			//platform dependent values
	private int CHEVRON_VERTICAL_TRIM = -1;
	private static final int CHEVRON_LEFT_MARGIN = 2;
	private static final int CHEVRON_IMAGE_WIDTH = 8;	//Width to draw the double arrow

	ToolBar chevron;
	boolean wrap;
	Image arrowImage = null;

/**
 * Constructs a new instance of this class given its parent
 * (which must be a CoolBar) and a style value
 * describing its behavior and appearance. The item is added
 * to the end of the items maintained by its parent.
 * 
 * The style value is either one of the style constants defined in
 * class SWT which is applicable to instances of this
 * class, or must be built by bitwise OR'ing together
 * (that is, using the int "|" operator) two or more
 * of those SWT style constants. The class description
 * lists the style constants that are applicable to the class.
 * Style bits are also inherited from superclasses.
 * 
 *
 * @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 
 *    ERROR_NULL_ARGUMENT - if the parent is null
 * 
 * @exception SWTException 
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
 *    ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
 * 
 *
 * @see SWT#DROP_DOWN
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public CoolItem (CoolBar parent, int style) {
	super(parent, style);
	this.parent = parent;
	parent.createItem (this, parent.getItemCount());
	calculateChevronTrim ();
}
/**
 * Constructs a new instance of this class given its parent
 * (which must be a CoolBar), a style value
 * describing its behavior and appearance, and the index
 * at which to place it in the items maintained by its parent.
 * 
 * The style value is either one of the style constants defined in
 * class SWT which is applicable to instances of this
 * class, or must be built by bitwise OR'ing together
 * (that is, using the int "|" operator) two or more
 * of those SWT style constants. The class description
 * lists the style constants that are applicable to the class.
 * Style bits are also inherited from superclasses.
 * 
 *
 * @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 at which to store the receiver in its parent
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the parent is null
 *    ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)
 * 
 * @exception SWTException 
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
 *    ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
 * 
 *
 * @see SWT#DROP_DOWN
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public CoolItem (CoolBar parent, int style, int index) {
	super(parent, style);
	this.parent = parent;
	parent.createItem (this, index);
	calculateChevronTrim ();
}
/**
 * Adds the listener to the collection of listeners that will
 * be notified when the control is selected by the user, by sending it one
 * of the messages defined in the SelectionListener
 * interface.
 * 
 * If widgetSelected is called when the mouse is over
 * the drop-down arrow (or 'chevron') portion of the cool item,
 * the event object detail field contains the value SWT.ARROW,
 * and the x and y fields in the event object represent the point at
 * the bottom left of the chevron, where the menu should be popped up.
 * widgetDefaultSelected is not called.
 * 
 *
 * @param listener the listener which should be notified when the control is selected by the user
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the listener is null
 * 
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 *
 * @see SelectionListener
 * @see #removeSelectionListener
 * @see SelectionEvent
 *
 * @since 2.0
 */
public void addSelectionListener(SelectionListener listener) {
	addTypedListener(listener, SWT.Selection, SWT.DefaultSelection);
}
@Override
protected void checkSubclass () {
	if (!isValidSubclass ()) error (SWT.ERROR_INVALID_SUBCLASS);
}
/*
 * Find the trim size of the Toolbar widget in the current platform.
 */
void calculateChevronTrim () {
	ToolBar tb = new ToolBar (parent, SWT.FLAT);
	ToolItem ti = new ToolItem (tb, SWT.PUSH);
	Image image = new Image (display, 1, 1);
	ti.setImage (image);
	Point size = tb.computeSize (SWT.DEFAULT, SWT.DEFAULT);
	size = parent.fixPoint(size.x, size.y);
	CHEVRON_HORIZONTAL_TRIM = size.x - 1;
	CHEVRON_VERTICAL_TRIM = size.y - 1;
	tb.dispose ();
	ti.dispose ();
	image.dispose ();
}
/**
 * Returns the preferred size of the receiver.
 * 
 * The preferred size of a CoolItem is the size that
 * it would best be displayed at. The width hint and height hint arguments
 * allow the caller to ask the instance questions such as "Given a particular
 * width, how high does it need to be to show all of the contents?"
 * To indicate that the caller does not wish to constrain a particular
 * dimension, the constant SWT.DEFAULT is passed for the hint.
 * 
 *
 * @param wHint the width hint (can be SWT.DEFAULT)
 * @param hHint the height hint (can be SWT.DEFAULT)
 * @return the preferred size
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 *
 * @see Layout
 * @see #getBounds
 * @see #getSize
 * @see Control#getBorderWidth
 * @see Scrollable#computeTrim
 * @see Scrollable#getClientArea
 */
public Point computeSize (int wHint, int hHint) {
	checkWidget();
	int width = wHint, height = hHint;
	if (wHint == SWT.DEFAULT) width = 32;
	if (hHint == SWT.DEFAULT) height = 32;
	if ((parent.style & SWT.VERTICAL) != 0) {
		height += MINIMUM_WIDTH;
	} else {
		width += MINIMUM_WIDTH;
	}
	return new Point (width, height);
}
@Override
public void dispose () {
	if (isDisposed()) return;

	/*
	 * Must call parent.destroyItem() before super.dispose(), since it needs to
	 * query the bounds to properly remove the item.
	 */
	parent.destroyItem(this);
	super.dispose ();
	parent = null;
	control = null;

	/*
	 * Although the parent for the chevron is the CoolBar (CoolItem can not be the parent)
	 * it has to be disposed with the item
	 */
	if (chevron != null && !chevron.isDisposed()) chevron.dispose();
	chevron = null;
	if (arrowImage != null && !arrowImage.isDisposed()) arrowImage.dispose();
	arrowImage = null;
}

Image createArrowImage (int width, int height) {
	Point point = parent.fixPoint(width, height);
	width = point.x;
	height = point.y;
	Color foreground = parent.getForeground ();
	Color black = display.getSystemColor (SWT.COLOR_BLACK);
	Color background = parent.getBackground ();

	PaletteData palette = new PaletteData (foreground.getRGB(), background.getRGB(), black.getRGB());
	ImageData imageData = new ImageData (width, height, 4, palette);
	imageData.transparentPixel = 1;
	Image image = new Image (display, imageData);

	GC gc = new GC (image, parent.getStyle() & SWT.RIGHT_TO_LEFT);
	gc.setBackground (background);
	gc.fillRectangle (0, 0, width, height);
	gc.setForeground (black);

	int startX = 0 ;
	if ((parent.style & SWT.VERTICAL) != 0) {
		startX = width - CHEVRON_IMAGE_WIDTH;
	}
	int startY = height / 6;
	int step = 2;
	gc.drawLine (startX, startY, startX + step, startY + step);
	gc.drawLine (startX, startY + (2 * step), startX + step, startY + step);
	startX++;
	gc.drawLine (startX, startY, startX + step, startY + step);
	gc.drawLine (startX, startY + (2 * step), startX + step, startY + step);
	startX += 3;
	gc.drawLine (startX, startY, startX + step, startY + step);
	gc.drawLine (startX, startY + (2 * step), startX + step, startY + step);
	startX++;
	gc.drawLine (startX, startY, startX + step, startY + step);
	gc.drawLine (startX, startY + (2 * step), startX + step, startY + step);
	gc.dispose ();
	return image;
}
/**
 * Returns a rectangle describing the receiver's size and location
 * relative to its parent.
 *
 * @return the receiver's bounding rectangle
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public Rectangle getBounds () {
	checkWidget();
	return parent.fixRectangle(itemBounds.x, itemBounds.y, itemBounds.width, itemBounds.height);
}
Rectangle internalGetBounds () {
	return new Rectangle(itemBounds.x, itemBounds.y, itemBounds.width, itemBounds.height);
}
/**
 * Returns the control that is associated with the receiver.
 *
 * @return the control that is contained by the receiver
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public Control getControl () {
	checkWidget();
	return control;
}
/**
 * Returns the minimum size that the cool item can
 * be resized to using the cool item's gripper.
 *
 * @return a point containing the minimum width and height of the cool item, in SWT logical points
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 *
 * @since 2.0
 */
public Point getMinimumSize () {
	checkWidget();
	return parent.fixPoint(minimumWidth, minimumHeight);
}
/**
 * Returns the receiver's parent, which must be a CoolBar.
 *
 * @return the receiver's parent
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public CoolBar getParent () {
	checkWidget();
	return parent;
}
/**
 * Returns a point describing the receiver's ideal size.
 * The x coordinate of the result is the ideal width of the receiver.
 * The y coordinate of the result is the ideal height of the receiver.
 *
 * @return the receiver's ideal size
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public Point getPreferredSize () {
	checkWidget();
	return parent.fixPoint(preferredWidth, preferredHeight);
}
/**
 * Returns a point describing the receiver's size. The
 * x coordinate of the result is the width of the receiver.
 * The y coordinate of the result is the height of the
 * receiver.
 *
 * @return the receiver's size
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public Point getSize () {
	checkWidget();
	return parent.fixPoint(itemBounds.width, itemBounds.height);
}
int internalGetMinimumWidth () {
	int width = minimumWidth + MINIMUM_WIDTH;
	if ((style & SWT.DROP_DOWN) != 0 && width < preferredWidth) {
		width += CHEVRON_IMAGE_WIDTH + CHEVRON_HORIZONTAL_TRIM + CHEVRON_LEFT_MARGIN;
	}
	return width;
}
/*
 *  Called when the chevron is selected.
 */
void onSelection (Event ev) {
	Rectangle bounds = chevron.getBounds();
	Event event = new Event();
	event.detail = SWT.ARROW;
	if ((parent.style & SWT.VERTICAL) != 0) {
		event.x = bounds.x + bounds.width;
		event.y = bounds.y;
	} else {
		event.x = bounds.x;
		event.y = bounds.y + bounds.height;
	}
	event.stateMask = ev.stateMask;
	sendSelectionEvent (SWT.Selection, event, false);
}
/**
 * Removes the listener from the collection of listeners that
 * will be notified when the control is selected by the user.
 *
 * @param listener the listener which should no longer be notified
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the listener is null
 * 
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 *
 * @see SelectionListener
 * @see #addSelectionListener
 *
 * @since 2.0
 */
public void removeSelectionListener(SelectionListener listener) {
	checkWidget();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Selection, listener);
	eventTable.unhook (SWT.DefaultSelection,listener);
}
void setBounds (int x, int y, int width, int height) {
	itemBounds.x = x;
	itemBounds.y = y;
	itemBounds.width = width;
	itemBounds.height = height;
	if (control != null) {
		int controlWidth = width - MINIMUM_WIDTH;
		if ((style & SWT.DROP_DOWN) != 0 && width < preferredWidth) {
			controlWidth -= CHEVRON_IMAGE_WIDTH + CHEVRON_HORIZONTAL_TRIM + CHEVRON_LEFT_MARGIN;
		}
		if (height > preferredHeight) {
			y += (height - preferredHeight) / 2;
			height = preferredHeight;
		}
		control.setBounds (parent.fixRectangle(x + MINIMUM_WIDTH, y, controlWidth, height));
	}
	updateChevron();
}
/**
 * Sets the control that is associated with the receiver
 * to the argument.
 *
 * @param control the new control that will be contained by the receiver
 *
 * @exception IllegalArgumentException 
 *    ERROR_INVALID_ARGUMENT - if the control has been disposed
 *    ERROR_INVALID_PARENT - if the control is not in the same widget tree
 * 
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public void setControl (Control control) {
	checkWidget();
	if (control != null) {
		if (control.isDisposed()) error (SWT.ERROR_INVALID_ARGUMENT);
		if (control.parent != parent) error (SWT.ERROR_INVALID_PARENT);
	}
	this.control = control;
	if (control != null) {
		int controlWidth = itemBounds.width - MINIMUM_WIDTH;
		if ((style & SWT.DROP_DOWN) != 0 && itemBounds.width < preferredWidth) {
			controlWidth -= CHEVRON_IMAGE_WIDTH + CHEVRON_HORIZONTAL_TRIM + CHEVRON_LEFT_MARGIN;
		}
		control.setBounds (parent.fixRectangle(itemBounds.x + MINIMUM_WIDTH, itemBounds.y, controlWidth, itemBounds.height));
	}
}
/**
 * Sets the minimum size that the cool item can be resized to
 * using the cool item's gripper, to the point specified by the arguments.
 *
 * @param width the minimum width of the cool item, in SWT logical points
 * @param height the minimum height of the cool item, in SWT logical points
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 *
 * @since 2.0
 */
public void setMinimumSize (int width, int height) {
	checkWidget ();
	Point point = parent.fixPoint(width, height);
	minimumWidth = point.x;
	minimumHeight = point.y;
}
/**
 * Sets the minimum size that the cool item can be resized to
 * using the cool item's gripper, to the point specified by the argument.
 *
 * @param size a point representing the minimum width and height of the cool item, in SWT logical points
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the point is null
 * 
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 *
 * @since 2.0
 */
public void setMinimumSize (Point size) {
	checkWidget ();
	if (size == null) error(SWT.ERROR_NULL_ARGUMENT);
	setMinimumSize(size.x, size.y);
}
/**
 * Sets the receiver's ideal size to the point specified by the arguments.
 *
 * @param width the new ideal width for the receiver
 * @param height the new ideal height for the receiver
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public void setPreferredSize (int width, int height) {
	checkWidget();
	ideal = true;
	Point point = parent.fixPoint(width, height);
	preferredWidth = Math.max (point.x, MINIMUM_WIDTH);
	preferredHeight = point.y;
}
/**
 * Sets the receiver's ideal size to the point specified by the argument.
 *
 * @param size the new ideal size for the receiver
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the point is null
 * 
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public void setPreferredSize (Point size) {
	checkWidget();
	if (size == null) error(SWT.ERROR_NULL_ARGUMENT);
	setPreferredSize(size.x, size.y);
}
/**
 * Sets the receiver's size to the point specified by the arguments.
 * 
 * Note: Attempting to set the width or height of the
 * receiver to a negative number will cause that
 * value to be set to zero instead.
 * 
 *
 * @param width the new width for the receiver
 * @param height the new height for the receiver
 *
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public void setSize (int width, int height) {
	checkWidget();
	Point point = parent.fixPoint(width, height);
	width = Math.max(point.x, minimumWidth + MINIMUM_WIDTH);
	height = point.y;
	if (!ideal) {
		preferredWidth = width;
		preferredHeight = height;
	}
	itemBounds.width = requestedWidth = width;
	itemBounds.height = height;
	if (control != null) {
		int controlWidth = width - MINIMUM_WIDTH;
		if ((style & SWT.DROP_DOWN) != 0 && width < preferredWidth) {
			controlWidth -= CHEVRON_IMAGE_WIDTH + CHEVRON_HORIZONTAL_TRIM + CHEVRON_LEFT_MARGIN;
		}
		control.setSize(parent.fixPoint(controlWidth, height));
	}
	parent.relayout();
	updateChevron();
}
/**
 * Sets the receiver's size to the point specified by the argument.
 * 
 * Note: Attempting to set the width or height of the
 * receiver to a negative number will cause them to be
 * set to zero instead.
 * 
 *
 * @param size the new size for the receiver
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the point is null
 * 
 * @exception SWTException 
 *    ERROR_WIDGET_DISPOSED - if the receiver has been disposed
 *    ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
 * 
 */
public void setSize (Point size) {
	checkWidget();
	if (size == null) error (SWT.ERROR_NULL_ARGUMENT);
	setSize (size.x, size.y);
}
void updateChevron() {
	if (control != null) {
		int width = itemBounds.width;
		if ((style & SWT.DROP_DOWN) != 0 && width < preferredWidth) {
			if (chevron == null) {
				chevron = new ToolBar (parent, SWT.FLAT | SWT.NO_FOCUS);
				ToolItem toolItem = new ToolItem (chevron, SWT.PUSH);
				toolItem.addListener (SWT.Selection, event -> CoolItem.this.onSelection (event));
			}
			int controlHeight, currentImageHeight = 0;
			if ((parent.style & SWT.VERTICAL) != 0) {
				controlHeight = control.getSize ().x;
				if (arrowImage != null) currentImageHeight = arrowImage.getBounds().width;
			} else {
				controlHeight = control.getSize ().y;
				if (arrowImage != null) currentImageHeight = arrowImage.getBounds().height;
			}
			int height = Math.min (controlHeight, itemBounds.height);
			int imageHeight = Math.max(1, height - CHEVRON_VERTICAL_TRIM);
			if (currentImageHeight != imageHeight) {
				Image image = createArrowImage (CHEVRON_IMAGE_WIDTH, imageHeight);
				chevron.getItem (0).setImage (image);
				if (arrowImage != null) arrowImage.dispose ();
				arrowImage = image;
			}
			chevron.setBackground (parent.getBackground());
			chevron.setBounds (parent.fixRectangle (
				itemBounds.x + width - CHEVRON_LEFT_MARGIN - CHEVRON_IMAGE_WIDTH - CHEVRON_HORIZONTAL_TRIM,
				itemBounds.y,
				CHEVRON_IMAGE_WIDTH + CHEVRON_HORIZONTAL_TRIM,
				height));
			chevron.setVisible(true);
		} else {
			if (chevron != null) {
				chevron.setVisible(false);
			}
		}
	}
}
}