org.eclipse.swt.widgets.CoolItem Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of org.eclipse.swt.gtk.linux.x86 Show documentation
SWT is an open source widget toolkit for Java designed to provide efficient, portable access to the user-interface facilities of the operating systems on which it is implemented.
The newest version!
/*******************************************************************************
 * Copyright (c) 2000, 2009 IBM Corporation 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:
 *     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) {
	checkWidget();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener (listener);
	addListener (SWT.Selection,typedListener);
	addListener (SWT.DefaultSelection,typedListener);
}
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);
}
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 (new RGB[]{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 pixels
 * 
 * @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 pixels
 * @param height the minimum height of the cool item, in pixels
 * 
 * @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 pixels
 * 
 * @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, new Listener() {
					public void handleEvent (Event 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);
			}
		}
	}
}
}