/*******************************************************************************
* Copyright (c) 2012 Laurent CARON
* 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:
* Laurent CARON (laurent.caron at gmail dot com) - initial API and implementation
*******************************************************************************/
package org.mihalis.opal.obutton;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Widget;
/**
* Instances of this class represent a selectable user interface object that issues notification when pressed and released.
* <dl>
* <dt><b>Styles:</b></dt>
* <dd>ARROW, PUSH, TOGGLE</dd>
* <dd>UP, DOWN, LEFT, RIGHT, CENTER</dd>
* <dt><b>Events:</b></dt>
* <dd>Selection</dd>
* </dl>
* <p>
* Note: Only one of the styles ARROW, PUSH and TOGGLE may be specified.
* </p>
* <p>
* Note: Only one of the styles LEFT, RIGHT, and CENTER may be specified.
* </p>
* <p>
* Note: Only one of the styles UP, DOWN, LEFT, and RIGHT may be specified when the ARROW style is specified.
* </p>
*/
public class OButton extends Canvas {
private static final String IS_BUTTON_PRESSED = OButton.class.toString() + "_pressed";
private final List<SelectionListener> selectionListeners;
int alignment = SWT.LEFT;
private ButtonRenderer buttonRenderer;
boolean selected;
boolean hover;
String text;
Image image;
private int width;
private int height;
private boolean clicked;
/**
* 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#ARROW
* @see SWT#CHECK
* @see SWT#PUSH
* @see SWT#RADIO
* @see SWT#TOGGLE
* @see SWT#FLAT
* @see SWT#UP
* @see SWT#DOWN
* @see SWT#LEFT
* @see SWT#RIGHT
* @see SWT#CENTER
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public OButton(final Composite parent, final int style) {
super(parent, checkStyle(style) | SWT.DOUBLE_BUFFERED);
this.selectionListeners = new ArrayList<SelectionListener>();
this.buttonRenderer = DefaultButtonRenderer.getInstance();
this.width = this.height = -1;
addListeners();
}
private static int checkStyle(int style) {
style = checkBits(style, SWT.PUSH, SWT.ARROW, SWT.TOGGLE, 0);
if ((style & (SWT.PUSH | SWT.TOGGLE)) != 0) {
return checkBits(style, SWT.CENTER, SWT.LEFT, SWT.RIGHT, 0);
}
if ((style & SWT.ARROW) != 0) {
return checkBits(style, SWT.UP, SWT.DOWN, SWT.LEFT, SWT.RIGHT);
}
return style;
}
private static int checkBits(int style, final int int0, final int int1, final int int2, final int int3) {
final int mask = int0 | int1 | int2 | int3;
if ((style & mask) == 0) {
style |= int0;
}
if ((style & int0) != 0) {
style = style & ~mask | int0;
}
if ((style & int1) != 0) {
style = style & ~mask | int1;
}
if ((style & int2) != 0) {
style = style & ~mask | int2;
}
if ((style & int3) != 0) {
style = style & ~mask | int3;
}
return style;
}
private void addListeners() {
final Listener listener = new Listener() {
@Override
public void handleEvent(final Event event) {
switch (event.type) {
case SWT.MouseEnter:
OButton.this.hover = true;
redraw();
update();
break;
case SWT.MouseExit:
OButton.this.hover = false;
redraw();
update();
break;
case SWT.MouseDown:
OButton.this.clicked = true;
OButton.this.setData(IS_BUTTON_PRESSED, "*");
redraw();
update();
break;
case SWT.MouseUp:
if (OButton.this.getData(IS_BUTTON_PRESSED) == null) {
return;
}
OButton.this.setData(IS_BUTTON_PRESSED, null);
OButton.this.clicked = false;
OButton.this.selected = !OButton.this.selected;
redraw();
update();
fireSelectionEvent();
break;
case SWT.Paint:
handlePaintEvent(event);
break;
case SWT.KeyDown:
if (event.keyCode == SWT.TAB) {
if (event.stateMask == SWT.SHIFT) {
OButton.this.traverse(SWT.TRAVERSE_TAB_PREVIOUS);
} else {
OButton.this.traverse(SWT.TRAVERSE_TAB_NEXT);
}
}
break;
case SWT.Dispose:
OButton.this.buttonRenderer.dispose();
break;
}
}
};
final int[] events = new int[] { SWT.MouseEnter, SWT.MouseExit, SWT.MouseDown, SWT.MouseUp, SWT.Paint, SWT.Dispose };
for (final int event : events) {
addListener(event, listener);
}
}
protected void fireSelectionEvent() {
final Event event = new Event();
event.widget = this;
event.display = getDisplay();
event.type = SWT.Selection;
for (final SelectionListener selectionListener : this.selectionListeners) {
selectionListener.widgetSelected(new SelectionEvent(event));
}
}
private void handlePaintEvent(final Event event) {
if (!isEnabled()) {
this.buttonRenderer.drawButtonWhenDisabled(event.gc, this);
return;
}
if (this.clicked) {
this.buttonRenderer.drawButtonWhenClicked(event.gc, this);
return;
}
if (this.hover) {
this.buttonRenderer.drawButtonWhenMouseHover(event.gc, this);
return;
}
final boolean isToggleButton = (getStyle() & SWT.TOGGLE) == SWT.TOGGLE;
if (isToggleButton && this.selected) {
this.buttonRenderer.drawButtonWhenSelected(event.gc, this);
return;
}
this.buttonRenderer.drawButton(event.gc, this);
}
/**
* Adds the listener to the collection of listeners who will be notified when the control is selected by the user, by sending it one of the messages defined in the <code>SelectionListener</code> interface.
* <p>
* <code>widgetSelected</code> is called when the control is selected by the user. <code>widgetDefaultSelected</code> is not called.
* </p>
*
* @param listener the listener which should be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener 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>
*
* @see SelectionListener
* @see #removeSelectionListener
* @see SelectionEvent
*/
public void addSelectionListener(final SelectionListener listener) {
checkWidget();
if (listener == null) {
SWT.error(SWT.ERROR_NULL_ARGUMENT);
}
this.selectionListeners.add(listener);
}
/**
* @see org.eclipse.swt.widgets.Composite#computeSize(int, int, boolean)
*/
@Override
public Point computeSize(final int wHint, final int hHint, final boolean changed) {
checkWidget();
final Point computedSize = this.buttonRenderer.computeSize(this, wHint, hHint, changed);
if (wHint != SWT.DEFAULT) {
computedSize.x = wHint;
}
if (hHint != SWT.DEFAULT) {
computedSize.y = hHint;
}
setWidth(computedSize.x);
setHeight(computedSize.y);
return computedSize;
}
/**
* Returns a value which describes the position of the text or image in the receiver. The value will be one of <code>LEFT</code>, <code>RIGHT</code> or <code>CENTER</code> unless the receiver is an <code>ARROW</code> button, in which case, the
* alignment will indicate the direction of the arrow (one of <code>LEFT</code>, <code>RIGHT</code>, <code>UP</code> or <code>DOWN</code>).
*
* @return the alignment
*
* @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 getAlignment() {
checkWidget();
return this.alignment;
}
/**
* @return the associated button renderer
*/
public ButtonRenderer getButtonRenderer() {
checkWidget();
return this.buttonRenderer;
}
/**
* Returns the whole height of the widget.
*
* @return the receiver's height
*
* @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 getHeight() {
checkWidget();
if (this.height == -1) {
return this.computeSize(SWT.DEFAULT, SWT.DEFAULT, false).y;
}
return this.height;
}
/**
* Returns the receiver's image if it has one, or null if it does not.
*
* @return the receiver's image
*
* @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 this.image;
}
/**
* Returns <code>true</code> if the receiver is selected, and false otherwise.
*
* @return the selection state
*
* @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 getSelection() {
checkWidget();
return this.selected;
}
/**
* Returns the receiver's text, which will be an empty string if it has never been set or if the receiver is an <code>ARROW</code> button.
*
* @return the receiver's 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>
*/
public String getText() {
checkWidget();
return this.text;
}
/**
* Returns the whole width of the widget.
*
* @return the receiver's height
*
* @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 getWidth() {
checkWidget();
if (this.width == -1) {
return computeSize(SWT.DEFAULT, SWT.DEFAULT, false).x;
}
return this.width;
}
/**
* Removes the listener from the collection of listeners who will be notified when the control is selected by the user.
*
* @param listener the listener which should no longer be notified
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the listener 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>
*
* @see SelectionListener
* @see #addSelectionListener
*/
public void removeSelectionListener(final SelectionListener listener) {
checkWidget();
if (listener == null) {
SWT.error(SWT.ERROR_NULL_ARGUMENT);
}
this.selectionListeners.remove(listener);
}
/**
* Controls how text, images and arrows will be displayed in the receiver. The argument should be one of <code>LEFT</code>, <code>RIGHT</code> or <code>CENTER</code> unless the receiver is an <code>ARROW</code> button, in which case, the argument
* indicates the direction of the arrow (one of <code>LEFT</code>, <code>RIGHT</code>, <code>UP</code> or <code>DOWN</code>).
*
* @param alignment the new alignment
*
* @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 setAlignment(final int alignment) {
checkWidget();
if (alignment != SWT.LEFT && alignment != SWT.RIGHT && alignment != SWT.CENTER) {
SWT.error(SWT.ERROR_INVALID_ARGUMENT);
}
this.alignment = alignment;
redraw();
update();
}
/**
* @param buttonRenderer the button renderer to set
*/
public void setButtonRenderer(final ButtonRenderer buttonRenderer) {
this.buttonRenderer = buttonRenderer;
}
/**
* Sets the height of the receiver.
* <p>
* 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.
* </p>
*
* @param height the new width
*
* @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 setHeight(final int height) {
checkWidget();
this.height = Math.max(height, 0);
redraw();
update();
}
/**
* Sets the receiver's image to the argument, which may be <code>null</code> indicating that no image should be displayed.
*
* @param image the image to display on the receiver (may be <code>null</code>)
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_INVALID_ARGUMENT - if the image 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 void setImage(final Image image) {
checkWidget();
if (image != null && image.isDisposed()) {
SWT.error(SWT.ERROR_INVALID_ARGUMENT);
}
this.image = image;
this.buttonRenderer.createDisabledImage();
redraw();
update();
}
/**
* Sets the selection state of the receiver, if it is of type <code>TOGGLE</code>.
*
* @param selected the new selection state
*
* @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 setSelection(final boolean selected) {
checkWidget();
this.selected = selected;
redraw();
update();
}
/**
* Sets the receiver's text.
*
* @param string the new text
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the text 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>
*/
public void setText(final String string) {
checkWidget();
this.text = string;
redraw();
update();
}
/**
* Sets the width of the receiver.
* <p>
* 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.
* </p>
*
* @param width the new width
*
* @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 setWidth(final int width) {
checkWidget();
this.width = Math.max(0, width);
redraw();
update();
}
/**
* @see org.eclipse.swt.widgets.Control#setEnabled(boolean)
*/
@Override
public void setEnabled(final boolean enabled) {
super.setEnabled(enabled);
redraw();
update();
}
/**
* @see org.eclipse.swt.widgets.Control#setSize(int, int)
*/
@Override
public void setSize(final int width, final int height) {
super.setSize(width, height);
redraw();
update();
}
/**
* @see org.eclipse.swt.widgets.Control#setSize(org.eclipse.swt.graphics.Point)
*/
@Override
public void setSize(final Point size) {
super.setSize(size);
redraw();
update();
}
/**
* @see org.eclipse.swt.widgets.Control#setVisible(boolean)
*/
@Override
public void setVisible(final boolean visible) {
super.setVisible(visible);
redraw();
update();
}
}