bundles/org.eclipse.swt/Eclipse SWT/wpf/org/eclipse/swt/widgets/Spinner.java

/*******************************************************************************
 * 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.graphics.*;
import org.eclipse.swt.internal.wpf.*;
import org.eclipse.swt.events.*;

/**
 * Instances of this class are selectable user interface
 * objects that allow the user to enter and modify numeric
 * values.
 * <p>
 * Note that although this class is a subclass of <code>Composite</code>,
 * it does not make sense to add children to it, or set a layout on it.
 * </p><p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>READ_ONLY, WRAP</dd>
 * <dt><b>Events:</b></dt>
 * <dd>Selection, Modify, Verify</dd>
 * </dl>
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#spinner">Spinner 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>
 * 
 * @since 3.1
 * @noextend This class is not intended to be subclassed by clients.
 */
public class Spinner extends Composite {
	int textHandle, upHandle, downHandle;
	int increment, pageIncrement, digits, max, min, value;
	
	/**
	 * the operating system limit for the number of characters
	 * that the text field in an instance of this class can hold
	 * 
	 * @since 3.4
	 */
	public static final int LIMIT;
	
	/*
	 * These values can be different on different platforms.
	 * Therefore they are not initialized in the declaration
	 * to stop the compiler from inlining.
	 */
	static {
		LIMIT = 0x7FFFFFFF;	
	}
/**
 * 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#READ_ONLY
 * @see SWT#WRAP
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public Spinner (Composite parent, int style) {
	super (parent, checkStyle (style));
}

Control [] _getChildren () {
	return new Control [0];
}

static int checkStyle (int style) {
	/*
	* Even though it is legal to create this widget
	* with scroll bars, they serve no useful purpose
	* because they do not automatically scroll the
	* widget's client area.  The fix is to clear
	* the SWT style.
	*/
	return style & ~(SWT.H_SCROLL | SWT.V_SCROLL);
}

protected void checkSubclass () {
	if (!isValidSubclass ()) error (SWT.ERROR_INVALID_SUBCLASS);
}

int backgroundHandle () {
	return textHandle;
}

int backgroundProperty () {
	return OS.Control_BackgroundProperty ();
}

public Point computeSize (int wHint, int hHint, boolean changed) {
	checkWidget ();
	return super.computeSize (handle, wHint, hHint, changed);
}

int createArrow (int direction) { 
	int geometry = OS.gcnew_StreamGeometry ();
	int context = OS.StreamGeometry_Open (geometry);
	int start = 0, point = 0, end = 0;
	switch (direction) {
		case SWT.DOWN:
			start = OS.gcnew_Point (0, 0);
			point = OS.gcnew_Point (3, 3);
			end = OS.gcnew_Point (6, 0);
			break;
		case SWT.UP:
			start = OS.gcnew_Point (0, 3);
			point = OS.gcnew_Point (3, 0);
			end = OS.gcnew_Point (6, 3);
			break;
	}
	OS.StreamGeometryContext_BeginFigure (context, start, true, true);
	OS.StreamGeometryContext_LineTo (context, point, true, true);
	OS.StreamGeometryContext_LineTo (context, end, true, true);
	OS.StreamGeometryContext_Close (context);
	int path = OS.gcnew_Path ();
	OS.Path_Data (path, geometry);
	int padding = OS.gcnew_Thickness (3, 0, 3, 0);
	OS.FrameworkElement_Margin (path, padding);
	int brush = OS.Brushes_Black ();
	OS.Path_Fill (path, brush);
	OS.FrameworkElement_HorizontalAlignment (path, OS.HorizontalAlignment_Center);
	OS.FrameworkElement_VerticalAlignment (path, OS.VerticalAlignment_Center);
	OS.GCHandle_Free (padding);
	OS.GCHandle_Free (start);
	OS.GCHandle_Free (point);
	OS.GCHandle_Free (end);
	OS.GCHandle_Free (brush);
	OS.GCHandle_Free (context);
	OS.GCHandle_Free (geometry);
	return path;
}

void createHandle () {
	handle = OS.gcnew_Grid ();
	if (handle == 0) error (SWT.ERROR_NO_HANDLES);
	int row0 = OS.gcnew_RowDefinition ();
	int row1 = OS.gcnew_RowDefinition ();
	int rows = OS.Grid_RowDefinitions (handle);
	OS.RowDefinitionCollection_Add (rows, row0);
	OS.RowDefinitionCollection_Add (rows, row1);
	int col0 = OS.gcnew_ColumnDefinition ();
	int col1 = OS.gcnew_ColumnDefinition ();
	int columns = OS.Grid_ColumnDefinitions (handle);
	OS.ColumnDefinitionCollection_Add (columns, col0);
	OS.ColumnDefinitionCollection_Add (columns, col1);
	int gridChildren = OS.Panel_Children (handle);
	textHandle = OS.gcnew_TextBox ();
	if (textHandle == 0) error (SWT.ERROR_NO_HANDLES);
	OS.Grid_SetRowSpan (textHandle, 2);
	OS.UIElementCollection_Add (gridChildren, textHandle);
	if ((style & SWT.READ_ONLY) != 0) OS.TextBoxBase_IsReadOnly (textHandle, true);
	upHandle = OS.gcnew_RepeatButton ();
	if (upHandle == 0) error (SWT.ERROR_NO_HANDLES);
	int upArrow = createArrow (SWT.UP);
	OS.ContentControl_Content (upHandle, upArrow);
	OS.Grid_SetColumn (upHandle, 1);
	OS.UIElementCollection_Add (gridChildren, upHandle);
	downHandle = OS.gcnew_RepeatButton ();
	if (downHandle == 0) error (SWT.ERROR_NO_HANDLES);
	int downArrow = createArrow (SWT.DOWN);
	OS.ContentControl_Content (downHandle, downArrow);
	OS.Grid_SetColumn (downHandle, 1);
	OS.Grid_SetRow (downHandle, 1);
	OS.UIElementCollection_Add (gridChildren, downHandle);
	int colWidth0 = OS.gcnew_GridLength (10, OS.GridUnitType_Star);
	OS.ColumnDefinition_Width(col0, colWidth0);
	int colWidth1 = OS.gcnew_GridLength (1, OS.GridUnitType_Auto);
	OS.ColumnDefinition_Width (col1, colWidth1);
	OS.GCHandle_Free (colWidth0);
	OS.GCHandle_Free (colWidth1);
	OS.GCHandle_Free (upArrow);
	OS.GCHandle_Free (downArrow);
	OS.GCHandle_Free (row0);
	OS.GCHandle_Free (row1);
	OS.GCHandle_Free (rows);
	OS.GCHandle_Free (col0);
	OS.GCHandle_Free (col1);
	OS.GCHandle_Free (columns);
	OS.GCHandle_Free (gridChildren);
}

void createWidget () {
	super.createWidget();
	increment = 1;
	pageIncrement = 10;
	digits = 0;
	max = 100;
	value = 0;
	int ptr = createDotNetString ("0", false);
	OS.TextBox_Text (textHandle, ptr);
	OS.GCHandle_Free (ptr);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the receiver's text is modified, by sending
 * it one of the messages defined in the <code>ModifyListener</code>
 * interface.
 *
 * @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 ModifyListener
 * @see #removeModifyListener
 */
public void addModifyListener (ModifyListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener (listener);
	addListener (SWT.Modify, typedListener);
}

/**
 * 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 not called for texts.
 * <code>widgetDefaultSelected</code> is typically called when ENTER is pressed in a single-line text.
 * </p>
 *
 * @param listener the listener which should be notified when the control is selected by the user
 *
 * @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(SelectionListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener (listener);
	addListener (SWT.Selection,typedListener);
	addListener (SWT.DefaultSelection,typedListener);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the receiver's text is verified, by sending
 * it one of the messages defined in the <code>VerifyListener</code>
 * interface.
 *
 * @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 VerifyListener
 * @see #removeVerifyListener
 */
void addVerifyListener (VerifyListener listener) {
	checkWidget();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener (listener);
	addListener (SWT.Verify, typedListener);
}

/**
 * Copies the selected text.
 * <p>
 * The current selection is copied to the clipboard.
 * </p>
 *
 * @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 copy () {
	checkWidget ();
	//TODO
}

/**
 * Cuts the selected text.
 * <p>
 * The current selection is first copied to the
 * clipboard and then deleted from the widget.
 * </p>
 *
 * @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 cut () {
	checkWidget ();
	if ((style & SWT.READ_ONLY) != 0) return;
	//TODO
}

/**
 * Returns the number of decimal places used by the receiver.
 *
 * @return the digits
 *
 * @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 getDigits () {
	checkWidget ();
	return digits;
}

String getDecimalSeparator () {
	return ".";
}

/**
 * Returns the amount that the receiver's value will be
 * modified by when the up/down 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 max;
}

/**
 * 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 min;
}

/**
 * Returns the amount that the receiver's position will be
 * modified by when the page up/down keys are pressed.
 *
 * @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 <em>selection</em>, 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 value;
}

int getSelectionText (boolean [] parseFail) {
	int textPtr = OS.TextBox_Text (textHandle);
	String string = createJavaString (textPtr);
	OS.GCHandle_Free (textPtr);
	try {
		int value;
		if (digits > 0) {
			String decimalSeparator = getDecimalSeparator ();
			int index = string.indexOf (decimalSeparator);
			if (index != -1)  {
				int startIndex = string.startsWith ("+") || string.startsWith ("-") ? 1 : 0;
				String wholePart = startIndex != index ? string.substring (startIndex, index) : "0";
				String decimalPart = string.substring (index + 1);
				if (decimalPart.length () > digits) {
					decimalPart = decimalPart.substring (0, digits);
				} else {
					int i = digits - decimalPart.length ();
					for (int j = 0; j < i; j++) {
						decimalPart = decimalPart + "0";
					}
				}
				int wholeValue = Integer.parseInt (wholePart);
				int decimalValue = Integer.parseInt (decimalPart);
				for (int i = 0; i < digits; i++) wholeValue *= 10;
				value = wholeValue + decimalValue;
				if (string.startsWith ("-")) value = -value;
			} else {
				value = Integer.parseInt (string);
				for (int i = 0; i < digits; i++) value *= 10;
			}
		} else {
			value = Integer.parseInt (string);
		}
		if (min <= value && value <= max) return value;
	} catch (NumberFormatException e) {
	}
	parseFail [0] = true;
	return -1;
}

/**
 * Returns a string containing a copy of the contents of the
 * receiver's text field, or an empty string if there are no
 * contents.
 *
 * @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>
 * 
 * @since 3.4
 */
public String getText () {
	checkWidget ();
	int text = OS.TextBox_Text (textHandle);
	String string = createJavaString (text);
	OS.GCHandle_Free (text);
	return string;
}

/**
 * Returns the maximum number of characters that the receiver's
 * text field is capable of holding. If this has not been changed
 * by <code>setTextLimit()</code>, it will be the constant
 * <code>Spinner.LIMIT</code>.
 * 
 * @return the text limit
 * 
 * @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 #LIMIT
 * 
 * @since 3.4
 */
public int getTextLimit () {
	checkWidget ();
	return OS.TextBox_MaxLength (textHandle);
}

void HandleDownClick (int sender, int e) {
	if (!checkEvent (e)) return;
	updateSelection (-increment);
}

void HandleLostKeyboardFocus (int sender, int e) {
	if (!checkEvent (e)) return;
	boolean [] parseFail = new boolean [1];
	getSelectionText (parseFail);
	if (parseFail [0]) {
		setSelection (value, false, true, false);
	}
	super.HandleLostKeyboardFocus (sender, e);
}

void HandlePreviewKeyDown (int sender, int e) {
	super.HandlePreviewKeyDown (sender, e);
	if (!checkEvent (e)) return;
	int key = OS.KeyEventArgs_Key (e);
	int delta = 0;
	switch (key) {
		case OS.Key_Return:
			postEvent (SWT.DefaultSelection);
			break;
		case OS.Key_Down: delta -= increment; break;
		case OS.Key_Up: delta += increment; break;
		case OS.Key_PageDown: delta -= pageIncrement; break;
		case OS.Key_PageUp: delta += pageIncrement; break;
	}
	if (delta != 0) {
		updateSelection (delta);
	}
}

void HandlePreviewTextInput (int sender, int e) {
	super.HandlePreviewTextInput (sender, e);
	if (!checkEvent (e)) return;
	int textPtr = OS.TextCompositionEventArgs_Text (e);
	String input = createJavaString(textPtr);
	OS.GCHandle_Free (textPtr);
	int start = OS.TextBox_SelectionStart (textHandle);
	int end = start + OS.TextBox_SelectionLength (textHandle);
	String text = verifyText (input, start, end);
	if (text != null && !text.equals (input)) {
		textPtr = createDotNetString (text, false);
		OS.TextBox_SelectedText (textHandle, textPtr);
		OS.GCHandle_Free (textPtr);
		start = OS.TextBox_SelectionStart (textHandle);
		int length = OS.TextBox_SelectionLength (textHandle);
		OS.TextBox_Select (textHandle, start+length, 0);
		OS.TextBox_SelectionLength (textHandle, 0);
		text = null;
	}
	if (text == null) OS.TextCompositionEventArgs_Handled (e, true);
}

void HandleTextChanged (int sender, int e) {
	if (!checkEvent (e)) return;
	boolean [] parseFail = new boolean [1];
	int value = getSelectionText (parseFail);
	if (!parseFail [0]) {
		if (this.value != value) setSelection(value, true, false, true);
	}
	sendEvent (SWT.Modify);
}

void HandleUpClick (int sender, int e) {
	if (!checkEvent (e)) return;
	updateSelection (increment);
}

void hookEvents () {
	super.hookEvents();	
	//TEXT
	int handler = OS.gcnew_TextCompositionEventHandler (jniRef, "HandlePreviewTextInput");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.UIElement_PreviewTextInput (textHandle, handler);
	OS.GCHandle_Free (handler);
//	handler = OS.gcnew_ExecutedRoutedEventHandler(jniRef, "HandlePreviewExecutedRoutedEvent");
//	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
//	OS.CommandManager_AddPreviewExecutedHandler(handle, handler);
//	OS.GCHandle_Free(handler);
	handler = OS.gcnew_TextChangedEventHandler (jniRef, "HandleTextChanged");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.TextBoxBase_TextChanged (textHandle, handler);
	OS.GCHandle_Free (handler);
	
	//BUTTON
	handler = OS.gcnew_RoutedEventHandler (jniRef, "HandleDownClick");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.ButtonBase_Click (downHandle, handler);
	OS.GCHandle_Free (handler);
	handler = OS.gcnew_RoutedEventHandler (jniRef, "HandleUpClick");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.ButtonBase_Click (upHandle, handler);
	OS.GCHandle_Free (handler);
}

/**
 * Pastes text from clipboard.
 * <p>
 * The selected text is deleted from the widget
 * and new text inserted from the clipboard.
 * </p>
 *
 * @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 paste () {
	checkWidget ();
	//TODO
}

void releaseHandle () {
	super.releaseHandle();
	OS.GCHandle_Free (textHandle);
	OS.GCHandle_Free (upHandle);
	OS.GCHandle_Free (downHandle);
}

/**
 * Removes the listener from the collection of listeners who will
 * be notified when the receiver's text is modified.
 *
 * @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 ModifyListener
 * @see #addModifyListener
 */
public void removeModifyListener (ModifyListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Modify, listener);	
}

/**
 * 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(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);	
}

/**
 * Removes the listener from the collection of listeners who will
 * be notified when the control is verified.
 *
 * @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 VerifyListener
 * @see #addVerifyListener
 */
void removeVerifyListener (VerifyListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Verify, listener);	
}

/**
 * Sets the number of decimal places used by the receiver.
 * <p>
 * The digit setting is used to allow for floating point values in the receiver.
 * For example, to set the selection to a floating point value of 1.37 call setDigits() with 
 * a value of 2 and setSelection() with a value of 137. Similarly, if getDigits() has a value
 * of 2 and getSelection() returns 137 this should be interpreted as 1.37. This applies to all
 * numeric APIs. 
 * </p>
 * 
 * @param value the new digits (must be greater than or equal to zero)
 * 
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the value is less than zero</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 setDigits (int value) {
	checkWidget ();
	if (value < 0) error (SWT.ERROR_INVALID_ARGUMENT);
	digits = value;
	setSelection (this.value, false, true, false);
}

/**
 * Sets the amount that the receiver's value will be
 * modified by when the up/down arrows are pressed to
 * the argument, which must be at least one.
 *
 * @param value 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;
	increment = value;
}

/**
 * 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 ();
	if (value <= min) return;
	max = value;
	if (this.value > value) setSelection (value, true, true, false);
}

/**
 * Sets the minimum value that the receiver will allow.  This new
 * value will be ignored if it 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 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 >= max) return;
	min = value;
	if (this.value < value) setSelection (value, true, true, false);
}

/**
 * Sets the amount that the receiver's position will be
 * modified by when the page up/down keys are pressed
 * to the argument, which must be at least one.
 *
 * @param value 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;
	pageIncrement = value;
}

/**
 * Sets the <em>selection</em>, which is the receiver's
 * position, to the argument. If the argument is not within
 * the range specified by minimum and maximum, it will be
 * adjusted to fall within this range.
 *
 * @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 ();
	value = Math.min (Math.max (min, value), max);
	setSelection (value, true, true, false);
}

void setSelection (int value, boolean setPos, boolean setText, boolean notify) {
	if (setPos) {
		this.value = value;
	}
	if (setText) {
		String string;
		if (digits == 0) {
			string = String.valueOf (value);
		} else {
			string = String.valueOf (Math.abs (value));
			String decimalSeparator = getDecimalSeparator ();
			int index = string.length () - digits;
			StringBuffer buffer = new StringBuffer ();
			if (value < 0) buffer.append ("-");
			if (index > 0) {
				buffer.append (string.substring (0, index));
				buffer.append (decimalSeparator);
				buffer.append (string.substring (index));
			} else {
				buffer.append ("0");
				buffer.append (decimalSeparator);
				while (index++ < 0) buffer.append ("0");
				buffer.append (string);
			}
			string = buffer.toString ();
		}
//		if (hooks (SWT.Verify) || filters (SWT.Verify)) {
//			int length = OS.GetWindowTextLength (hwndText);
//			string = verifyText (string, 0, length, null);
//			if (string == null) return;
//		}
		int ptr = createDotNetString (string, false);
		OS.TextBox_Text (textHandle, ptr);
		OS.GCHandle_Free (ptr);
	}
	if (notify) postEvent (SWT.Selection);
}

/**
 * Sets the maximum number of characters that the receiver's
 * text field is capable of holding to be the argument.
 * <p>
 * To reset this value to the default, use <code>setTextLimit(Spinner.LIMIT)</code>.
 * Specifying a limit value larger than <code>Spinner.LIMIT</code> sets the
 * receiver's limit to <code>Spinner.LIMIT</code>.
 * </p>
 * @param limit new text limit
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_CANNOT_BE_ZERO - if the limit is zero</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 #LIMIT
 * 
 * @since 3.4
 */
public void setTextLimit (int limit) {
	checkWidget ();
	if (limit == 0) error (SWT.ERROR_CANNOT_BE_ZERO);
	OS.TextBox_MaxLength (textHandle, limit);
}

/**
 * Sets the receiver's selection, minimum value, maximum
 * value, digits, increment and page increment all at once.
 * <p>
 * Note: This is similar to setting the values individually
 * using the appropriate methods, but may be implemented in a 
 * more efficient fashion on some platforms.
 * </p>
 *
 * @param selection the new selection value
 * @param minimum the new minimum value
 * @param maximum the new maximum value
 * @param digits the new digits value
 * @param increment the new increment value
 * @param pageIncrement the new pageIncrement value
 *
 * @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>
 * 
 * @since 3.2
 */
public void setValues (int selection, int minimum, int maximum, int digits, int increment, int pageIncrement) {
	checkWidget ();
	if (maximum <= minimum) return;
	if (digits < 0) return;
	if (increment < 1) return;
	if (pageIncrement < 1) return;
	selection = Math.min (Math.max (minimum, selection), maximum);
	this.pageIncrement = pageIncrement;
	this.increment = increment;
	this.digits = digits;
	this.min = minimum;
	this.max = maximum;
	setSelection (selection, true, true, false);
}

void updateSelection (int delta) { 
	boolean [] parseFail = new boolean [1];
	int value = getSelectionText (parseFail);
	if (parseFail [0]) value = this.value;
	int newValue = value + delta;
	if ((style & SWT.WRAP) != 0) {
		if (newValue < min) newValue = max;
		if (newValue > max) newValue = min;
	}
	newValue = Math.min (Math.max (min, newValue), max);
	if (value != newValue) setSelection (newValue, true, true, true);
}

String verifyText (String string, int start, int end) {
	Event event = new Event ();
	event.text = string;
	event.start = start;
	event.end = end;
	if (string.length () == 1) {
		event.character = string.charAt (0);
		setInputState (event, SWT.KeyDown, 0, 0);
	}
	int index = 0;
	if (digits > 0) {
		String decimalSeparator = getDecimalSeparator ();
		index = string.indexOf (decimalSeparator);
		if (index != -1) {
			string = string.substring (0, index) + string.substring (index + 1);
		}
		index = 0;
	}
	if (string.length() > 0) {
		if (min < 0 && string.charAt (0) == '-') index++;
	}
	while (index < string.length ()) {
		if (!Character.isDigit (string.charAt (index))) break;
		index++;
	}
	event.doit = index == string.length ();
	sendEvent (SWT.Verify, event);
	if (!event.doit || isDisposed ()) return null;
	return event.text;
}

}