| /******************************************************************************* |
| * Copyright (c) 2000, 2004 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.widgets; |
| |
| |
| import org.eclipse.swt.internal.win32.*; |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.events.*; |
| |
| /** |
| * Instances of this class are selectable user interface |
| * objects that represent a range of positive, numeric values. |
| * <p> |
| * At any given moment, a given scroll bar will have a |
| * single <em>selection</em> that is considered to be its |
| * value, which is constrained to be within the range of |
| * values the scroll bar represents (that is, between its |
| * <em>minimum</em> and <em>maximum</em> values). |
| * </p><p> |
| * Typically, scroll bars will be made up of five areas: |
| * <ol> |
| * <li>an arrow button for decrementing the value</li> |
| * <li>a page decrement area for decrementing the value by a larger amount</li> |
| * <li>a <em>thumb</em> for modifying the value by mouse dragging</li> |
| * <li>a page increment area for incrementing the value by a larger amount</li> |
| * <li>an arrow button for incrementing the value</li> |
| * </ol> |
| * Based on their style, scroll bars are either <code>HORIZONTAL</code> |
| * (which have a left facing button for decrementing the value and a |
| * right facing button for incrementing it) or <code>VERTICAL</code> |
| * (which have an upward facing button for decrementing the value |
| * and a downward facing buttons for incrementing it). |
| * </p><p> |
| * On some platforms, the size of the scroll bar's thumb can be |
| * varied relative to the magnitude of the range of values it |
| * represents (that is, relative to the difference between its |
| * maximum and minimum values). Typically, this is used to |
| * indicate some proportional value such as the ratio of the |
| * visible area of a document to the total amount of space that |
| * it would take to display it. SWT supports setting the thumb |
| * size even if the underlying platform does not, but in this |
| * case the appearance of the scroll bar will not change. |
| * </p><p> |
| * Scroll bars are created by specifying either <code>H_SCROLL</code>, |
| * <code>V_SCROLL</code> or both when creating a <code>Scrollable</code>. |
| * They are accessed from the <code>Scrollable</code> using |
| * <code>getHorizontalBar</code> and <code>getVerticalBar</code>. |
| * </p><p> |
| * Note: Scroll bars are not Controls. On some platforms, scroll bars |
| * that appear as part of some standard controls such as a text or list |
| * have no operating system resources and are not children of the control. |
| * For this reason, scroll bars are treated specially. To create a control |
| * that looks like a scroll bar but has operating system resources, use |
| * <code>Slider</code>. |
| * </p> |
| * <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> |
| * IMPORTANT: This class is <em>not</em> intended to be subclassed. |
| * </p> |
| * |
| * @see Slider |
| * @see Scrollable |
| * @see Scrollable#getHorizontalBar |
| * @see Scrollable#getVerticalBar |
| */ |
| |
| public class ScrollBar extends Widget { |
| Scrollable parent; |
| int increment, pageIncrement; |
| |
| /** |
| * 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 |
| */ |
| ScrollBar (Scrollable parent, int style) { |
| super (parent, checkStyle (style)); |
| this.parent = parent; |
| createWidget (); |
| } |
| |
| /** |
| * Adds the listener to the collection of listeners who will |
| * be notified when the receiver's value changes, by sending |
| * it one of the messages defined in the <code>SelectionListener</code> |
| * interface. |
| * <p> |
| * When <code>widgetSelected</code> is called, the event object detail field contains one of the following values: |
| * <code>0</code> - for the end of a drag. |
| * <code>SWT.DRAG</code>. |
| * <code>SWT.HOME</code>. |
| * <code>SWT.END</code>. |
| * <code>SWT.ARROW_DOWN</code>. |
| * <code>SWT.ARROW_UP</code>. |
| * <code>SWT.PAGE_DOWN</code>. |
| * <code>SWT.PAGE_UP</code>. |
| * <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 (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); |
| } |
| |
| void createWidget () { |
| increment = 1; |
| pageIncrement = 10; |
| /* |
| * Do not set the intial values of the maximum |
| * or the thumb. These values normally default |
| * to 100 and 10 but may have been set already |
| * by the widget that owns the scroll bar. For |
| * example, a scroll bar that is created for a |
| * list widget, setting these defaults would |
| * override the initial values provided by the |
| * list widget. |
| */ |
| } |
| |
| public void dispose () { |
| if (isDisposed()) return; |
| if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| super.dispose (); |
| if (OS.IsWinCE) { |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_RANGE | OS.SIF_PAGE; |
| info.nPage = 101; |
| info.nMax = 100; |
| info.nMin = 0; |
| OS.SetScrollInfo (hwnd, type, info, true); |
| } else { |
| OS.ShowScrollBar (hwnd, type, false); |
| } |
| } |
| |
| /* |
| * Not currently used. |
| */ |
| Rectangle getBounds () { |
| // checkWidget (); |
| parent.forceResize (); |
| RECT rect = new RECT (); |
| OS.GetClientRect (parent.handle, rect); |
| int x = 0, y = 0, width, height; |
| if ((style & SWT.HORIZONTAL) != 0) { |
| y = rect.bottom - rect.top; |
| width = rect.right - rect.left; |
| height = OS.GetSystemMetrics (OS.SM_CYHSCROLL); |
| } else { |
| x = rect.right - rect.left; |
| width = OS.GetSystemMetrics (OS.SM_CXVSCROLL); |
| height = rect.bottom - rect.top; |
| } |
| return new Rectangle (x, y, width, height); |
| } |
| |
| /** |
| * Returns <code>true</code> if the receiver is enabled, and |
| * <code>false</code> otherwise. A disabled control is typically |
| * not selectable from the user interface and draws with an |
| * inactive or "grayed" look. |
| * |
| * @return the receiver's enabled 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> |
| * |
| * @see #isEnabled |
| */ |
| public boolean getEnabled () { |
| checkWidget(); |
| return (state & DISABLED) == 0; |
| } |
| |
| /** |
| * 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(); |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_RANGE; |
| int hwnd = hwndScrollBar (); |
| int type = scrollBarType (); |
| OS.GetScrollInfo (hwnd, type, info); |
| return info.nMax; |
| } |
| |
| /** |
| * 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(); |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_RANGE; |
| int hwnd = hwndScrollBar (); |
| int type = scrollBarType (); |
| OS.GetScrollInfo (hwnd, type, info); |
| return info.nMin; |
| } |
| |
| /** |
| * 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 receiver's parent, which must be scrollable. |
| * |
| * @return the receiver's parent |
| * |
| * @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 Scrollable getParent () { |
| checkWidget(); |
| return parent; |
| } |
| |
| /** |
| * Returns the single <em>selection</em> that is the receiver's value. |
| * |
| * @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(); |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_POS; |
| int hwnd = hwndScrollBar (); |
| int type = scrollBarType (); |
| OS.GetScrollInfo (hwnd, type, info); |
| return info.nPos; |
| } |
| |
| /** |
| * 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 <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 Point getSize () { |
| checkWidget(); |
| parent.forceResize (); |
| RECT rect = new RECT (); |
| OS.GetClientRect (parent.handle, rect); |
| int width, height; |
| if ((style & SWT.HORIZONTAL) != 0) { |
| width = rect.right - rect.left; |
| height = OS.GetSystemMetrics (OS.SM_CYHSCROLL); |
| } else { |
| width = OS.GetSystemMetrics (OS.SM_CXVSCROLL); |
| height = rect.bottom - rect.top; |
| } |
| return new Point (width, height); |
| } |
| |
| /** |
| * Answers the size of the receiver's thumb relative to the |
| * difference between its maximum and minimum values. |
| * |
| * @return the thumb 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> |
| * |
| * @see ScrollBar |
| */ |
| public int getThumb () { |
| checkWidget(); |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_PAGE; |
| int hwnd = hwndScrollBar (); |
| int type = scrollBarType (); |
| OS.GetScrollInfo (hwnd, type, info); |
| if (info.nPage != 0) --info.nPage; |
| return info.nPage; |
| } |
| |
| /** |
| * Returns <code>true</code> if the receiver is visible, and |
| * <code>false</code> otherwise. |
| * <p> |
| * If one of the receiver's ancestors is not visible or some |
| * other condition makes the receiver not visible, this method |
| * may still indicate that it is considered visible even though |
| * it may not actually be showing. |
| * </p> |
| * |
| * @return the receiver's visibility 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 getVisible () { |
| checkWidget(); |
| return (state & HIDDEN) == 0; |
| } |
| |
| int hwndScrollBar () { |
| return parent.handle; |
| } |
| |
| /** |
| * Returns <code>true</code> if the receiver is enabled and all |
| * of the receiver's ancestors are enabled, and <code>false</code> |
| * otherwise. A disabled control is typically not selectable from the |
| * user interface and draws with an inactive or "grayed" look. |
| * |
| * @return the receiver's enabled 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> |
| * |
| * @see #getEnabled |
| */ |
| public boolean isEnabled () { |
| checkWidget(); |
| return getEnabled () && parent.isEnabled (); |
| } |
| |
| /** |
| * Returns <code>true</code> if the receiver is visible and all |
| * of the receiver's ancestors are visible and <code>false</code> |
| * otherwise. |
| * |
| * @return the receiver's visibility 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> |
| * |
| * @see #getVisible |
| */ |
| public boolean isVisible () { |
| checkWidget(); |
| return getVisible () && parent.isVisible (); |
| } |
| |
| void releaseChild () { |
| super.releaseChild (); |
| if (parent.horizontalBar == this) parent.horizontalBar = null; |
| if (parent.verticalBar == this) parent.verticalBar = null; |
| } |
| |
| void releaseWidget () { |
| super.releaseWidget (); |
| parent = null; |
| } |
| |
| /** |
| * Removes the listener from the collection of listeners who will |
| * be notified when the receiver's value changes. |
| * |
| * @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); |
| } |
| |
| int scrollBarType () { |
| if ((style & SWT.VERTICAL) != 0) return OS.SB_VERT; |
| /* |
| * This line is intentionally commented. There should |
| * only ever be HORIZONTAL and VERTICAL scroll bars. |
| * The commented code reminds us that this is the case |
| * and that the default style is HORIZONTAL. |
| */ |
| // if ((style & SWT.HORIZONTAL) != 0) return OS.SB_HORZ; |
| return OS.SB_HORZ; |
| } |
| |
| /** |
| * Enables the receiver if the argument is <code>true</code>, |
| * and disables it otherwise. A disabled control is typically |
| * not selectable from the user interface and draws with an |
| * inactive or "grayed" look. |
| * |
| * @param enabled the new enabled 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 setEnabled (boolean enabled) { |
| checkWidget(); |
| /* |
| * This line is intentionally commented. Currently |
| * always show scrollbar as being enabled and visible. |
| */ |
| // if (OS.IsWinCE) error (SWT.ERROR_NOT_IMPLEMENTED); |
| if (!OS.IsWinCE) { |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| int flags = enabled ? OS.ESB_ENABLE_BOTH : OS.ESB_DISABLE_BOTH; |
| OS.EnableScrollBar (hwnd, type, flags); |
| if (enabled) { |
| state &= ~DISABLED; |
| } else { |
| state |= DISABLED; |
| } |
| } |
| } |
| |
| /** |
| * 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 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. If this value is negative or less than or |
| * equal to the minimum, the value is ignored. If necessary, first |
| * the thumb and then the selection are adjusted to fit within the |
| * new range. |
| * |
| * @param value the new 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 setMaximum (int value) { |
| checkWidget(); |
| if (value < 0) return; |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| info.fMask = OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; |
| OS.GetScrollInfo (hwnd, type, info); |
| if (value - info.nMin - info.nPage < 1) return; |
| info.nMax = value; |
| SetScrollInfo (hwnd, type, info, true); |
| } |
| |
| /** |
| * Sets the minimum value. If this value is negative or greater |
| * than or equal to the maximum, the value is ignored. If necessary, |
| * first the thumb and then the selection are adjusted to fit within |
| * the new range. |
| * |
| * @param value the new 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 setMinimum (int value) { |
| checkWidget(); |
| if (value < 0) return; |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| info.fMask = OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; |
| OS.GetScrollInfo (hwnd, type, info); |
| if (info.nMax - value - info.nPage < 1) return; |
| info.nMin = value; |
| SetScrollInfo (hwnd, type, info, true); |
| } |
| |
| /** |
| * 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 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; |
| } |
| |
| boolean SetScrollInfo (int hwnd, int flags, SCROLLINFO info, boolean fRedraw) { |
| /* |
| * Bug in Windows. For some reason, when SetScrollInfo() |
| * is used with SIF_POS and the scroll bar is hidden, |
| * the opposite scroll bar is incorrectly made visible |
| * so that the next time the parent is resized (or another |
| * scroll bar operation is performed), the opposite scroll |
| * bar draws. The fix is to hide both scroll bars. |
| */ |
| if ((state & (DISABLED | HIDDEN)) != 0) fRedraw = false; |
| boolean result = OS.SetScrollInfo (hwnd, flags, info, fRedraw); |
| |
| /* |
| * Bug in Windows. For some reason, when the widget |
| * is a standard scroll bar, and SetScrollInfo() is |
| * called with SIF_RANGE or SIF_PAGE, the widget is |
| * incorrectly made visible so that the next time the |
| * parent is resized (or another scroll bar operation |
| * is performed), the scroll bar draws. The fix is |
| * to hide the scroll bar (again) when already hidden. |
| */ |
| if ((state & HIDDEN) != 0) { |
| /* |
| * This line is intentionally commented. Currently |
| * always show scrollbar as being enabled and visible. |
| */ |
| // if (OS.IsWinCE) error (SWT.ERROR_NOT_IMPLEMENTED); |
| if (!OS.IsWinCE) { |
| ScrollBar bar = null; |
| switch (flags) { |
| case OS.SB_HORZ: |
| bar = parent.getVerticalBar (); |
| break; |
| case OS.SB_VERT: |
| bar = parent.getHorizontalBar (); |
| break; |
| } |
| boolean both = bar != null && !bar.getVisible (); |
| OS.ShowScrollBar (hwnd, both ? OS.SB_BOTH : flags, false); |
| } |
| } |
| |
| /* |
| * Feature in Windows. Using SIF_DISABLENOSCROLL, |
| * SetScrollInfo () can change enabled and disabled |
| * state of the scroll bar causing a scroll bar that |
| * was disabled by the application to become enabled. |
| * The fix is to disable the scroll bar (again) when |
| * the application has disabled the scroll bar. |
| */ |
| if ((state & DISABLED) != 0) { |
| /* |
| * This line is intentionally commented. Currently |
| * always show scrollbar as being enabled and visible. |
| */ |
| // if (OS.IsWinCE) error (SWT.ERROR_NOT_IMPLEMENTED); |
| if (!OS.IsWinCE) { |
| OS.EnableScrollBar (hwnd, flags, OS.ESB_DISABLE_BOTH); |
| } |
| } |
| return result; |
| } |
| |
| /** |
| * Sets the single <em>selection</em> that 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(); |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| info.fMask = OS.SIF_POS; |
| info.nPos = selection; |
| SetScrollInfo (hwnd, type, info, true); |
| } |
| |
| /** |
| * Sets the size of the receiver's thumb relative to the |
| * difference between its maximum and minimum values. This new |
| * value will be ignored if it is less than one, and will be |
| * clamped if it exceeds the receiver's current range. |
| * |
| * @param value the new thumb value, which must be at least one and not |
| * larger than the size of the current range |
| * |
| * @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 setThumb (int value) { |
| checkWidget(); |
| if (value < 1) return; |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| info.fMask = OS.SIF_PAGE | OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; |
| OS.GetScrollInfo (hwnd, type, info); |
| info.nPage = value; |
| if (info.nPage != 0) info.nPage++; |
| SetScrollInfo (hwnd, type, info, true); |
| } |
| |
| /** |
| * Sets the receiver's selection, minimum value, maximum |
| * value, thumb, increment and page increment all at once. |
| * <p> |
| * Note: This is equivalent 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 thumb the new thumb 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> |
| */ |
| public void setValues (int selection, int minimum, int maximum, int thumb, int increment, int pageIncrement) { |
| checkWidget(); |
| if (minimum < 0) return; |
| if (maximum < 0) return; |
| if (thumb < 1) return; |
| if (increment < 1) return; |
| if (pageIncrement < 1) return; |
| this.increment = increment; |
| this.pageIncrement = pageIncrement; |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_POS | OS.SIF_PAGE | OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; |
| info.nPos = selection; |
| info.nMin = minimum; |
| info.nMax = maximum; |
| info.nPage = thumb; |
| if (info.nPage != 0) info.nPage++; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| SetScrollInfo (hwnd, type, info, true); |
| } |
| |
| /** |
| * Marks the receiver as visible if the argument is <code>true</code>, |
| * and marks it invisible otherwise. |
| * <p> |
| * If one of the receiver's ancestors is not visible or some |
| * other condition makes the receiver not visible, marking |
| * it visible may not actually cause it to be displayed. |
| * </p> |
| * |
| * @param visible the new visibility 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 setVisible (boolean visible) { |
| checkWidget(); |
| boolean isVisible = (state & HIDDEN) == 0; |
| if (isVisible == visible) return; |
| |
| /* |
| * On Windows CE, use SIF_DISABLENOSCROLL to show and |
| * hide the scroll bar when the page size is equal to |
| * the range. |
| */ |
| if (OS.IsWinCE) { |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| info.fMask = OS.SIF_RANGE | OS.SIF_PAGE; |
| if (visible) info.fMask |= OS.SIF_DISABLENOSCROLL; |
| OS.GetScrollInfo (hwnd, type, info); |
| if (info.nPage == info.nMax - info.nMin + 1) { |
| /* |
| * Bug in Windows. When the only changed flag to |
| * SetScrollInfo () is OS.SIF_DISABLENOSCROLL, |
| * Windows does not update the scroll bar state. |
| * The fix is to increase and then decrease the |
| * maximum, causing Windows to honour the flag. |
| */ |
| int max = info.nMax; |
| info.nMax++; |
| OS.SetScrollInfo (hwnd, type, info, false); |
| info.nMax = max; |
| OS.SetScrollInfo (hwnd, type, info, true); |
| } else { |
| /* |
| * This line is intentionally commented. Currently |
| * always show scrollbar as being enabled and visible. |
| */ |
| // if (OS.IsWinCE) error (SWT.ERROR_NOT_IMPLEMENTED); |
| } |
| return; |
| } |
| |
| /* |
| * Set the state bits before calling ShowScrollBar () |
| * because hiding and showing the scroll bar can cause |
| * WM_SIZE messages when the client area is resized. |
| * Setting the state before the call means that code |
| * that runs during WM_SIZE that queries the visibility |
| * of the scroll bar will get the correct value. |
| */ |
| state = visible ? state & ~HIDDEN : state | HIDDEN; |
| int hwnd = hwndScrollBar (), type = scrollBarType (); |
| if (OS.ShowScrollBar (hwnd, type, visible)) { |
| /* |
| * Bug in Windows. For some reason, when the widget |
| * is a standard scroll bar, and SetScrollInfo () is |
| * called with SIF_RANGE or SIF_PAGE while the widget |
| * is not visible, the widget is incorrectly disabled |
| * even though the values for SIF_RANGE and SIF_PAGE, |
| * when set for a visible scroll bar would not disable |
| * the scroll bar. The fix is to enable the scroll bar |
| * when not disabled by the application and the current |
| * scroll bar ranges would cause the scroll bar to be |
| * enabled had they been set when the scroll bar was |
| * visible. |
| */ |
| if ((state & DISABLED) == 0) { |
| SCROLLINFO info = new SCROLLINFO (); |
| info.cbSize = SCROLLINFO.sizeof; |
| info.fMask = OS.SIF_RANGE | OS.SIF_PAGE; |
| OS.GetScrollInfo (hwnd, type, info); |
| if (info.nMax - info.nMin - info.nPage >= 0) { |
| OS.EnableScrollBar (hwnd, type, OS.ESB_ENABLE_BOTH); |
| } |
| } |
| sendEvent (visible ? SWT.Show : SWT.Hide); |
| // widget could be disposed at this point |
| } |
| } |
| |
| LRESULT wmScrollChild (int wParam, int lParam) { |
| |
| /* Do nothing when scrolling is ending */ |
| int code = wParam & 0xFFFF; |
| if (code == OS.SB_ENDSCROLL) return null; |
| |
| /* |
| * Send the event because WM_HSCROLL and |
| * WM_VSCROLL are sent from a modal message |
| * loop in Windows that is active when the |
| * user is scrolling. |
| */ |
| Event event = new Event (); |
| switch (code) { |
| /* |
| * This line is intentionally commented. Do not set the detail |
| * field to DRAG to indicate that the dragging has ended when the |
| * scroll bar is finally positioned in SB_THUMBPOSITION. |
| */ |
| // case OS.SB_THUMBPOSITION: break; |
| case OS.SB_THUMBTRACK: event.detail = SWT.DRAG; break; |
| case OS.SB_TOP: event.detail = SWT.HOME; break; |
| case OS.SB_BOTTOM: event.detail = SWT.END; break; |
| case OS.SB_LINEDOWN: event.detail = SWT.ARROW_DOWN; break; |
| case OS.SB_LINEUP: event.detail = SWT.ARROW_UP; break; |
| case OS.SB_PAGEDOWN: event.detail = SWT.PAGE_DOWN; break; |
| case OS.SB_PAGEUP: event.detail = SWT.PAGE_UP; break; |
| } |
| sendEvent (SWT.Selection, event); |
| // the widget could be destroyed at this point |
| return null; |
| } |
| |
| } |