/*******************************************************************************
* Copyright (c) 2000, 2008 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.internal.gtk.*;
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>
*
* @see <a href="http://www.eclipse.org/swt/snippets/#scale">Scale snippets</a>
* @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a>
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
* @noextend This class is not intended to be subclassed by clients.
*/
public class Scale extends Control {
/**
* 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));
}
/**
* 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 ();
if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
TypedListener typedListener = new TypedListener (listener);
addListener (SWT.Selection,typedListener);
addListener (SWT.DefaultSelection,typedListener);
}
static int checkStyle (int style) {
return checkBits (style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0);
}
public Point computeSize (int wHint, int hHint, boolean changed) {
checkWidget();
if (wHint != SWT.DEFAULT && wHint < 0) wHint = 0;
if (hHint != SWT.DEFAULT && hHint < 0) hHint = 0;
Point size = computeNativeSize(handle, wHint, hHint, changed);
if ((style & SWT.HORIZONTAL) != 0) {
if (wHint == SWT.DEFAULT) size.x = 2 * size.x;
} else {
if (hHint == SWT.DEFAULT) size.y = 2 * size.y;
}
return size;
}
void createHandle (int index) {
state |= HANDLE | THEME_BACKGROUND;
fixedHandle = OS.g_object_new (display.gtk_fixed_get_type (), 0);
if (fixedHandle == 0) error (SWT.ERROR_NO_HANDLES);
OS.gtk_fixed_set_has_window (fixedHandle, true);
int /*long*/ hAdjustment = OS.gtk_adjustment_new (0, 0, 100, 1, 10, 0);
if (hAdjustment == 0) error (SWT.ERROR_NO_HANDLES);
if ((style & SWT.HORIZONTAL) != 0) {
handle = OS.gtk_hscale_new (hAdjustment);
} else {
handle = OS.gtk_vscale_new (hAdjustment);
}
if (handle == 0) error (SWT.ERROR_NO_HANDLES);
OS.gtk_container_add (fixedHandle, handle);
OS.gtk_scale_set_digits (handle, 0);
OS.gtk_scale_set_draw_value (handle, false);
}
void hookEvents () {
super.hookEvents ();
OS.g_signal_connect_closure (handle, OS.value_changed, display.closures [VALUE_CHANGED], false);
}
/**
* 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 ();
int /*long*/ hAdjustment = OS.gtk_range_get_adjustment (handle);
GtkAdjustment adjustment = new GtkAdjustment ();
OS.memmove (adjustment, hAdjustment);
return (int) adjustment.step_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 ();
int /*long*/ hAdjustment = OS.gtk_range_get_adjustment (handle);
GtkAdjustment adjustment = new GtkAdjustment ();
OS.memmove (adjustment, hAdjustment);
return (int) adjustment.upper;
}
/**
* 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 ();
int /*long*/ hAdjustment = OS.gtk_range_get_adjustment (handle);
GtkAdjustment adjustment = new GtkAdjustment ();
OS.memmove (adjustment, hAdjustment);
return (int) adjustment.lower;
}
/**
* 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 ();
int /*long*/ hAdjustment = OS.gtk_range_get_adjustment (handle);
GtkAdjustment adjustment = new GtkAdjustment ();
OS.memmove (adjustment, hAdjustment);
return (int) adjustment.page_increment;
}
/**
* 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 ();
int /*long*/ hAdjustment = OS.gtk_range_get_adjustment (handle);
GtkAdjustment adjustment = new GtkAdjustment ();
OS.memmove (adjustment, hAdjustment);
return (int) adjustment.value;
}
int /*long*/ gtk_value_changed (int /*long*/ adjustment) {
postEvent (SWT.Selection);
return 0;
}
/**
* 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 ();
if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
if (eventTable == null) return;
eventTable.unhook (SWT.Selection, listener);
eventTable.unhook (SWT.DefaultSelection,listener);
}
/**
* 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 value) {
checkWidget ();
if (value < 1) return;
OS.g_signal_handlers_block_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
OS.gtk_range_set_increments (handle, value, getPageIncrement ());
OS.g_signal_handlers_unblock_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
}
/**
* 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 value 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 value) {
checkWidget ();
int minimum = getMinimum();
if (value <= minimum) return;
OS.g_signal_handlers_block_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
OS.gtk_range_set_range (handle, minimum, value);
OS.g_signal_handlers_unblock_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
}
/**
* 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 value 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 value) {
checkWidget ();
if (value < 0) return;
int maximum = getMaximum ();
if (value >= maximum) return;
OS.g_signal_handlers_block_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
OS.gtk_range_set_range (handle, value, maximum);
OS.g_signal_handlers_unblock_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
}
/**
* 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 value) {
checkWidget ();
if (value < 1) return;
OS.g_signal_handlers_block_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
OS.gtk_range_set_increments (handle, getIncrement (), value);
OS.g_signal_handlers_unblock_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
}
/**
* Sets the 'selection', which is the receiver's value,
* to the argument which must be greater than or equal to zero.
*
* @param value 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 value) {
checkWidget ();
OS.g_signal_handlers_block_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
OS.gtk_range_set_value (handle, value);
OS.g_signal_handlers_unblock_matched (handle, OS.G_SIGNAL_MATCH_DATA, 0, 0, 0, 0, VALUE_CHANGED);
}
}
