/*******************************************************************************
* Copyright (c) 2000, 2012 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.internal.win32.*;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
/**
* This class is the abstract superclass of all classes which
* represent controls that have standard scroll bars.
* <dl>
* <dt><b>Styles:</b></dt>
* <dd>H_SCROLL, V_SCROLL</dd>
* <dt><b>Events:</b>
* <dd>(none)</dd>
* </dl>
* <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/">Sample code and further information</a>
* @noextend This class is not intended to be subclassed by clients.
*/
public abstract class Scrollable extends Control {
ScrollBar horizontalBar, verticalBar;
/**
* Prevents uninitialized instances from being created outside the package.
*/
Scrollable () {
}
/**
* 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#H_SCROLL
* @see SWT#V_SCROLL
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public Scrollable (Composite parent, int style) {
super (parent, style);
}
long /*int*/ callWindowProc (long /*int*/ hwnd, int msg, long /*int*/ wParam, long /*int*/ lParam) {
if (handle == 0) return 0;
return OS.DefWindowProc (hwnd, msg, wParam, lParam);
}
/**
* Given a desired <em>client area</em> for the receiver
* (as described by the arguments), returns the bounding
* rectangle which would be required to produce that client
* area.
* <p>
* In other words, it returns a rectangle such that, if the
* receiver's bounds were set to that rectangle, the area
* of the receiver which is capable of displaying data
* (that is, not covered by the "trimmings") would be the
* rectangle described by the arguments (relative to the
* receiver's parent).
* </p>
*
* @param x the desired x coordinate of the client area
* @param y the desired y coordinate of the client area
* @param width the desired width of the client area
* @param height the desired height of the client area
* @return the required bounds to produce the given client area
*
* @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 #getClientArea
*/
public Rectangle computeTrim (int x, int y, int width, int height) {
checkWidget ();
long /*int*/ scrolledHandle = scrolledHandle ();
RECT rect = new RECT ();
OS.SetRect (rect, x, y, x + width, y + height);
int bits1 = OS.GetWindowLong (scrolledHandle, OS.GWL_STYLE);
int bits2 = OS.GetWindowLong (scrolledHandle, OS.GWL_EXSTYLE);
OS.AdjustWindowRectEx (rect, bits1, false, bits2);
if (horizontalBar != null) rect.bottom += OS.GetSystemMetrics (OS.SM_CYHSCROLL);
if (verticalBar != null) rect.right += OS.GetSystemMetrics (OS.SM_CXVSCROLL);
int nWidth = rect.right - rect.left, nHeight = rect.bottom - rect.top;
return new Rectangle (rect.left, rect.top, nWidth, nHeight);
}
ScrollBar createScrollBar (int type) {
ScrollBar bar = new ScrollBar (this, type);
if ((state & CANVAS) != 0) {
bar.setMaximum (100);
bar.setThumb (10);
}
return bar;
}
void createWidget () {
super.createWidget ();
if ((style & SWT.H_SCROLL) != 0) horizontalBar = createScrollBar (SWT.H_SCROLL);
if ((style & SWT.V_SCROLL) != 0) verticalBar = createScrollBar (SWT.V_SCROLL);
}
void destroyScrollBar (int type) {
long /*int*/ hwnd = scrolledHandle ();
int bits = OS.GetWindowLong (hwnd, OS.GWL_STYLE);
if ((type & SWT.HORIZONTAL) != 0) {
style &= ~SWT.H_SCROLL;
bits &= ~OS.WS_HSCROLL;
}
if ((type & SWT.VERTICAL) != 0) {
style &= ~SWT.V_SCROLL;
bits &= ~OS.WS_VSCROLL;
}
OS.SetWindowLong (hwnd, OS.GWL_STYLE, bits);
}
/**
* Returns a rectangle which describes the area of the
* receiver which is capable of displaying data (that is,
* not covered by the "trimmings").
*
* @return the client area
*
* @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 #computeTrim
*/
public Rectangle getClientArea () {
checkWidget ();
forceResize ();
RECT rect = new RECT ();
long /*int*/ scrolledHandle = scrolledHandle ();
OS.GetClientRect (scrolledHandle, rect);
int x = rect.left, y = rect.top;
int width = rect.right - rect.left;
int height = rect.bottom - rect.top;
if (scrolledHandle != handle) {
OS.GetClientRect (handle, rect);
OS.MapWindowPoints(handle, scrolledHandle, rect, 2);
x = -rect.left;
y = -rect.top;
}
return new Rectangle (x, y, width, height);
}
/**
* Returns the receiver's horizontal scroll bar if it has
* one, and null if it does not.
*
* @return the horizontal scroll bar (or null)
*
* @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 ScrollBar getHorizontalBar () {
checkWidget ();
return horizontalBar;
}
/**
* Returns the mode of the receiver's scrollbars. This will be
* <em>bitwise</em> OR of one or more of the constants defined in class
* <code>SWT</code>.<br>
* <li><code>SWT.SCROLLBAR_OVERLAY</code> - if receiver
* uses overlay scrollbars</li>
* <li><code>SWT.NONE</code> - otherwise</li>
*
* @return the mode of scrollbars
*
* @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 SWT#SCROLLBAR_OVERLAY
*
* @since 3.8
*/
public int getScrollbarsMode () {
checkWidget();
return SWT.NONE;
}
/**
* Returns the receiver's vertical scroll bar if it has
* one, and null if it does not.
*
* @return the vertical scroll bar (or null)
*
* @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 ScrollBar getVerticalBar () {
checkWidget ();
return verticalBar;
}
void releaseChildren (boolean destroy) {
if (horizontalBar != null) {
horizontalBar.release (false);
horizontalBar = null;
}
if (verticalBar != null) {
verticalBar.release (false);
verticalBar = null;
}
super.releaseChildren (destroy);
}
void reskinChildren (int flags) {
if (horizontalBar != null) horizontalBar.reskin (flags);
if (verticalBar != null) verticalBar.reskin (flags);
super.reskinChildren (flags);
}
long /*int*/ scrolledHandle () {
return handle;
}
int widgetExtStyle () {
return super.widgetExtStyle ();
/*
* This code is intentionally commented. In future,
* we may wish to support different standard Windows
* edge styles. The issue here is that not all of
* these styles are available on the other platforms
* this would need to be a hint.
*/
// if ((style & SWT.BORDER) != 0) return OS.WS_EX_CLIENTEDGE;
// if ((style & SWT.SHADOW_IN) != 0) return OS.WS_EX_STATICEDGE;
// return super.widgetExtStyle ();
}
int widgetStyle () {
int bits = super.widgetStyle () | OS.WS_TABSTOP;
if ((style & SWT.H_SCROLL) != 0) bits |= OS.WS_HSCROLL;
if ((style & SWT.V_SCROLL) != 0) bits |= OS.WS_VSCROLL;
return bits;
}
TCHAR windowClass () {
return display.windowClass;
}
long /*int*/ windowProc () {
return display.windowProc;
}
LRESULT WM_HSCROLL (long /*int*/ wParam, long /*int*/ lParam) {
LRESULT result = super.WM_HSCROLL (wParam, lParam);
if (result != null) return result;
/*
* Bug on WinCE. lParam should be NULL when the message is not sent
* by a scroll bar control, but it contains the handle to the window.
* When the message is sent by a scroll bar control, it correctly
* contains the handle to the scroll bar. The fix is to check for
* both.
*/
if (horizontalBar != null && (lParam == 0 || lParam == handle)) {
return wmScroll (horizontalBar, (state & CANVAS) != 0, handle, OS.WM_HSCROLL, wParam, lParam);
}
return result;
}
LRESULT WM_MOUSEWHEEL (long /*int*/ wParam, long /*int*/ lParam) {
return wmScrollWheel ((state & CANVAS) != 0, wParam, lParam);
}
LRESULT WM_SIZE (long /*int*/ wParam, long /*int*/ lParam) {
long /*int*/ code = callWindowProc (handle, OS.WM_SIZE, wParam, lParam);
super.WM_SIZE (wParam, lParam);
// widget may be disposed at this point
if (code == 0) return LRESULT.ZERO;
return new LRESULT (code);
}
LRESULT WM_VSCROLL (long /*int*/ wParam, long /*int*/ lParam) {
LRESULT result = super.WM_VSCROLL (wParam, lParam);
if (result != null) return result;
/*
* Bug on WinCE. lParam should be NULL when the message is not sent
* by a scroll bar control, but it contains the handle to the window.
* When the message is sent by a scroll bar control, it correctly
* contains the handle to the scroll bar. The fix is to check for
* both.
*/
if (verticalBar != null && (lParam == 0 || lParam == handle)) {
return wmScroll (verticalBar, (state & CANVAS) != 0, handle, OS.WM_VSCROLL, wParam, lParam);
}
return result;
}
LRESULT wmNCPaint (long /*int*/ hwnd, long /*int*/ wParam, long /*int*/ lParam) {
LRESULT result = super.wmNCPaint (hwnd, wParam, lParam);
if (result != null) return result;
/*
* Bug in Windows. On XP only (not Vista), Windows sometimes
* does not redraw the bottom right corner of a window that
* has scroll bars, causing pixel corruption. The fix is to
* always draw the corner.
*/
if (OS.COMCTL32_MAJOR >= 6 && OS.IsAppThemed ()) {
if (!OS.IsWinCE && OS.WIN32_VERSION < OS.VERSION (6, 0)) {
int bits1 = OS.GetWindowLong (hwnd, OS.GWL_STYLE);
if ((bits1 & (OS.WS_HSCROLL | OS.WS_VSCROLL)) != 0) {
RECT windowRect = new RECT ();
OS.GetWindowRect (hwnd, windowRect);
RECT trimRect = new RECT ();
int bits2 = OS.GetWindowLong (hwnd, OS.GWL_EXSTYLE);
OS.AdjustWindowRectEx (trimRect, bits1, false, bits2);
boolean hVisible = false, vVisible = false;
SCROLLBARINFO psbi = new SCROLLBARINFO ();
psbi.cbSize = SCROLLBARINFO.sizeof;
if (OS.GetScrollBarInfo (hwnd, OS.OBJID_HSCROLL, psbi)) {
hVisible = (psbi.rgstate [0] & OS.STATE_SYSTEM_INVISIBLE) == 0;
}
if (OS.GetScrollBarInfo (hwnd, OS.OBJID_VSCROLL, psbi)) {
vVisible = (psbi.rgstate [0] & OS.STATE_SYSTEM_INVISIBLE) == 0;
}
RECT cornerRect = new RECT ();
cornerRect.bottom = windowRect.bottom - windowRect.top - trimRect.bottom;
cornerRect.top = cornerRect.bottom - (vVisible ? OS.GetSystemMetrics (OS.SM_CYHSCROLL) : 0);
if ((bits2 & OS.WS_EX_LEFTSCROLLBAR) != 0) {
cornerRect.left = trimRect.left;
cornerRect.right = cornerRect.left + (hVisible ? OS.GetSystemMetrics (OS.SM_CXVSCROLL) : 0);
} else {
cornerRect.right = windowRect.right - windowRect.left - trimRect.right;
cornerRect.left = cornerRect.right - (hVisible ? OS.GetSystemMetrics (OS.SM_CXVSCROLL) : 0);
}
if (cornerRect.left != cornerRect.right && cornerRect.top != cornerRect.bottom) {
long /*int*/ hDC = OS.GetWindowDC (hwnd);
OS.FillRect (hDC, cornerRect, OS.COLOR_BTNFACE + 1);
Decorations shell = menuShell ();
if ((shell.style & SWT.RESIZE) != 0) {
long /*int*/ hwndScroll = shell.scrolledHandle ();
boolean drawGripper = hwnd == hwndScroll;
if (!drawGripper) {
RECT shellRect = new RECT ();
OS.GetClientRect (hwndScroll, shellRect);
OS.MapWindowPoints (hwndScroll, 0, shellRect, 2);
drawGripper = shellRect.right == windowRect.right && shellRect.bottom == windowRect.bottom;
}
if (drawGripper) {
OS.DrawThemeBackground (display.hScrollBarTheme(), hDC, OS.SBP_SIZEBOX, 0, cornerRect, null);
}
}
OS.ReleaseDC (hwnd, hDC);
}
}
}
}
return result;
}
LRESULT wmScrollWheel (boolean update, long /*int*/ wParam, long /*int*/ lParam) {
int scrollRemainder = display.scrollRemainder;
LRESULT result = super.WM_MOUSEWHEEL (wParam, lParam);
if (result != null) return result;
/*
* Translate WM_MOUSEWHEEL to WM_VSCROLL or WM_HSCROLL.
*/
if (update) {
if ((wParam & (OS.MK_SHIFT | OS.MK_CONTROL)) != 0) return result;
boolean vertical = verticalBar != null && verticalBar.getEnabled ();
boolean horizontal = horizontalBar != null && horizontalBar.getEnabled ();
int msg = vertical ? OS.WM_VSCROLL : horizontal ? OS.WM_HSCROLL : 0;
if (msg == 0) return result;
int [] linesToScroll = new int [1];
OS.SystemParametersInfo (OS.SPI_GETWHEELSCROLLLINES, 0, linesToScroll, 0);
int delta = OS.GET_WHEEL_DELTA_WPARAM (wParam);
boolean pageScroll = linesToScroll [0] == OS.WHEEL_PAGESCROLL;
if (!OS.IsWinCE && OS.WIN32_VERSION >= OS.VERSION (5, 1)) {
ScrollBar bar = vertical ? verticalBar : horizontalBar;
SCROLLINFO info = new SCROLLINFO ();
info.cbSize = SCROLLINFO.sizeof;
info.fMask = OS.SIF_POS;
OS.GetScrollInfo (handle, bar.scrollBarType (), info);
if (vertical && !pageScroll) delta *= linesToScroll [0];
int increment = pageScroll ? bar.getPageIncrement () : bar.getIncrement ();
info.nPos -= increment * delta / OS.WHEEL_DELTA;
OS.SetScrollInfo (handle, bar.scrollBarType (), info, true);
OS.SendMessage (handle, msg, OS.SB_THUMBPOSITION, 0);
} else {
int code = 0;
if (pageScroll) {
code = delta < 0 ? OS.SB_PAGEDOWN : OS.SB_PAGEUP;
} else {
code = delta < 0 ? OS.SB_LINEDOWN : OS.SB_LINEUP;
if (msg == OS.WM_VSCROLL) delta *= linesToScroll [0];
}
/* Check if the delta and the remainder have the same direction (sign) */
if ((delta ^ scrollRemainder) >= 0) delta += scrollRemainder;
int count = Math.abs (delta) / OS.WHEEL_DELTA;
for (int i=0; i<count; i++) {
OS.SendMessage (handle, msg, code, 0);
}
}
return LRESULT.ZERO;
}
/*
* When the native widget scrolls inside WM_MOUSEWHEEL, it
* may or may not send a WM_VSCROLL or WM_HSCROLL to do the
* actual scrolling. This depends on the implementation of
* each native widget. In order to ensure that application
* code is notified when the scroll bar moves, compare the
* scroll bar position before and after the WM_MOUSEWHEEL.
* If the native control sends a WM_VSCROLL or WM_HSCROLL,
* then the application has already been notified. If not
* explicitly send the event.
*/
int vPosition = verticalBar == null ? 0 : verticalBar.getSelection ();
int hPosition = horizontalBar == null ? 0 : horizontalBar.getSelection ();
long /*int*/ code = callWindowProc (handle, OS.WM_MOUSEWHEEL, wParam, lParam);
if (verticalBar != null) {
int position = verticalBar.getSelection ();
if (position != vPosition) {
Event event = new Event ();
event.detail = position < vPosition ? SWT.PAGE_UP : SWT.PAGE_DOWN;
verticalBar.sendSelectionEvent (SWT.Selection, event, true);
}
}
if (horizontalBar != null) {
int position = horizontalBar.getSelection ();
if (position != hPosition) {
Event event = new Event ();
event.detail = position < hPosition ? SWT.PAGE_UP : SWT.PAGE_DOWN;
horizontalBar.sendSelectionEvent (SWT.Selection, event, true);
}
}
return new LRESULT (code);
}
LRESULT wmScroll (ScrollBar bar, boolean update, long /*int*/ hwnd, int msg, long /*int*/ wParam, long /*int*/ lParam) {
LRESULT result = null;
if (update) {
int type = msg == OS.WM_HSCROLL ? OS.SB_HORZ : OS.SB_VERT;
SCROLLINFO info = new SCROLLINFO ();
info.cbSize = SCROLLINFO.sizeof;
info.fMask = OS.SIF_TRACKPOS | OS.SIF_POS | OS.SIF_RANGE;
OS.GetScrollInfo (hwnd, type, info);
info.fMask = OS.SIF_POS;
int code = OS.LOWORD (wParam);
switch (code) {
case OS.SB_ENDSCROLL: return null;
case OS.SB_THUMBPOSITION:
case OS.SB_THUMBTRACK:
/*
* Note: On WinCE, the value in SB_THUMBPOSITION is relative to nMin.
* Same for SB_THUMBPOSITION 'except' for the very first thumb track
* message which has the actual value of nMin. This is a problem when
* nMin is not zero.
*/
info.nPos = info.nTrackPos;
break;
case OS.SB_TOP:
info.nPos = info.nMin;
break;
case OS.SB_BOTTOM:
info.nPos = info.nMax;
break;
case OS.SB_LINEDOWN:
info.nPos += bar.getIncrement ();
break;
case OS.SB_LINEUP:
int increment = bar.getIncrement ();
info.nPos = Math.max (info.nMin, info.nPos - increment);
break;
case OS.SB_PAGEDOWN:
info.nPos += bar.getPageIncrement ();
break;
case OS.SB_PAGEUP:
int pageIncrement = bar.getPageIncrement ();
info.nPos = Math.max (info.nMin, info.nPos - pageIncrement);
break;
}
OS.SetScrollInfo (hwnd, type, info, true);
} else {
long /*int*/ code = callWindowProc (hwnd, msg, wParam, lParam);
result = code == 0 ? LRESULT.ZERO : new LRESULT (code);
}
bar.wmScrollChild (wParam, lParam);
return result;
}
}