| /******************************************************************************* |
| * Copyright (c) 2008, 2011 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.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.events.*; |
| |
| /** |
| * Instances of the receiver represent a selectable user interface object that |
| * present a range of continuous numeric values. |
| * <dl> |
| * <dt><b>Styles:</b></dt> |
| * <dd>HORIZONTAL, VERTICAL</dd> |
| * <dt><b>Events:</b></dt> |
| * <dd>Selection</dd> |
| * </dl> |
| * <p> |
| * Note: Only one of the styles HORIZONTAL and VERTICAL may be specified. |
| * </p> |
| * <p> |
| * <p> |
| * IMPORTANT: This class is intended to be subclassed <em>only</em> within the |
| * SWT implementation. |
| * </p> |
| * |
| * @since 1.2 |
| */ |
| public class Scale extends Control { |
| |
| private final Point PREFERRED_SIZE = new Point( 160, 41 ); |
| |
| private int increment; |
| private int maximum; |
| private int minimum; |
| private int pageIncrement; |
| private int selection; |
| |
| /** |
| * 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#HORIZONTAL |
| * @see SWT#VERTICAL |
| * @see Widget#checkSubclass |
| * @see Widget#getStyle |
| */ |
| public Scale( Composite parent, int style ) { |
| super( parent, checkStyle( style ) ); |
| maximum = 100; |
| increment = 1; |
| pageIncrement = 10; |
| } |
| |
| /** |
| * Adds the listener to the collection of listeners who will be notified when |
| * the user changes the receiver's value, by sending it one of the messages |
| * defined in the <code>SelectionListener</code> interface. |
| * <p> |
| * <code>widgetSelected</code> is called when the user changes the receiver's |
| * value. <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 |
| */ |
| public void addSelectionListener( SelectionListener listener ) { |
| checkWidget(); |
| SelectionEvent.addListener( this, listener ); |
| } |
| |
| /** |
| * Removes the listener from the collection of listeners who will be notified |
| * when the user changes the receiver's value. |
| * |
| * @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( SelectionListener listener ) { |
| checkWidget(); |
| SelectionEvent.removeListener( this, listener ); |
| } |
| |
| public Point computeSize( int wHint, int hHint, boolean changed ) { |
| checkWidget(); |
| int border = getBorderWidth(); |
| int width = border * 2, height = border * 2; |
| if( ( style & SWT.HORIZONTAL ) != 0 ) { |
| width += PREFERRED_SIZE.x; |
| height += PREFERRED_SIZE.y; |
| } else { |
| width += PREFERRED_SIZE.y; |
| height += PREFERRED_SIZE.x; |
| } |
| if( wHint != SWT.DEFAULT ) { |
| width = wHint + ( border * 2 ); |
| } |
| if( hHint != SWT.DEFAULT ) { |
| height = hHint + ( border * 2 ); |
| } |
| return new Point( width, height ); |
| } |
| |
| /** |
| * Returns the amount that the receiver's value will be modified by when the |
| * up/down (or right/left) arrows are pressed. |
| * |
| * @return the increment |
| * @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 getIncrement() { |
| checkWidget(); |
| return increment; |
| } |
| |
| /** |
| * Returns the maximum value which the receiver will allow. |
| * |
| * @return the maximum |
| * @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 getMaximum() { |
| checkWidget(); |
| return maximum; |
| } |
| |
| /** |
| * Returns the minimum value which the receiver will allow. |
| * |
| * @return the minimum |
| * @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 getMinimum() { |
| checkWidget(); |
| return minimum; |
| } |
| |
| /** |
| * Returns the amount that the receiver's value will be modified by when the |
| * page increment/decrement areas are selected. |
| * |
| * @return the page increment |
| * @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 getPageIncrement() { |
| checkWidget(); |
| return pageIncrement; |
| } |
| |
| /** |
| * Returns the 'selection', which is the receiver's position. |
| * |
| * @return the selection |
| * @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 getSelection() { |
| checkWidget(); |
| return selection; |
| } |
| |
| /** |
| * Sets the amount that the receiver's value will be modified by when the |
| * up/down (or right/left) arrows are pressed to the argument, which must be |
| * at least one. |
| * |
| * @param increment the new increment (must be greater than zero) |
| * @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 setIncrement( int increment ) { |
| checkWidget(); |
| if( increment >= 1 && increment <= maximum - minimum ) { |
| this.increment = increment; |
| } |
| } |
| |
| /** |
| * Sets the maximum value that the receiver will allow. This new value will be |
| * ignored if it is not greater than the receiver's current minimum value. If |
| * the new maximum is applied then the receiver's selection value will be |
| * adjusted if necessary to fall within its new range. |
| * |
| * @param maximum the new maximum, which must be greater than the current |
| * minimum |
| * @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 setMaximum( int maximum ) { |
| checkWidget(); |
| if( 0 <= minimum && minimum < maximum ) { |
| this.maximum = maximum; |
| if( selection > this.maximum ) { |
| selection = this.maximum; |
| } |
| } |
| } |
| |
| /** |
| * Sets the minimum value that the receiver will allow. This new value will be |
| * ignored if it is negative or is not less than the receiver's current |
| * maximum value. If the new minimum is applied then the receiver's selection |
| * value will be adjusted if necessary to fall within its new range. |
| * |
| * @param minimum the new minimum, which must be nonnegative and less than the |
| * current maximum |
| * @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 setMinimum( int minimum ) { |
| checkWidget(); |
| if( 0 <= minimum && minimum < this.maximum ) { |
| this.minimum = minimum; |
| if( selection < this.minimum ) { |
| selection = this.minimum; |
| } |
| } |
| } |
| |
| /** |
| * Sets the amount that the receiver's value will be modified by when the page |
| * increment/decrement areas are selected to the argument, which must be at |
| * least one. |
| * |
| * @param pageIncrement the page increment (must be greater than zero) |
| * @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 setPageIncrement( int pageIncrement ) { |
| checkWidget(); |
| if( pageIncrement >= 1 && pageIncrement <= maximum - minimum ) { |
| this.pageIncrement = pageIncrement; |
| } |
| } |
| |
| /** |
| * Sets the 'selection', which is the receiver's value, to the argument which |
| * must be greater than or equal to zero. |
| * |
| * @param selection the new selection (must be zero or greater) |
| * @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( int selection ) { |
| checkWidget(); |
| if( selection >= minimum && selection <= maximum ) { |
| this.selection = selection; |
| } |
| } |
| |
| private static int checkStyle( int style ) { |
| return checkBits( style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0 ); |
| } |
| |
| /////////////////// |
| // Widget overrides |
| |
| boolean isTabGroup() { |
| return true; |
| } |
| |
| } |