/*******************************************************************************
* Copyright (c) 2000, 2011 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.photon.*;
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 {
int scrolledHandle;
ScrollBar horizontalBar, verticalBar;
Scrollable () {
/* Do nothing */
}
/**
* 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);
}
void createStandardScrollBars () {
/* Search the handle to find the scroll bars */
int child = OS.PtWidgetChildFront (handle);
while (child != 0) {
if (OS.PtWidgetClass (child) == OS.PtScrollbar ()) {
int [] args = {OS.Pt_ARG_ORIENTATION, 0, 0};
OS.PtGetResources (child, args.length / 3, args);
switch (args [1]) {
case OS.Pt_HORIZONTAL:
if ((style & SWT.H_SCROLL) != 0) {
horizontalBar = new ScrollBar (this, SWT.HORIZONTAL, child);
}
break;
case OS.Pt_VERTICAL:
if ((style & SWT.V_SCROLL) != 0) {
verticalBar = new ScrollBar (this, SWT.VERTICAL, child);
}
break;
}
}
child = OS.PtWidgetBrotherBehind (child);
}
}
void deregister () {
super.deregister ();
if (scrolledHandle != 0) WidgetTable.remove (scrolledHandle);
}
/**
* 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();
PhRect_t rect = new PhRect_t ();
PhArea_t area = new PhArea_t ();
rect.ul_x = (short) x;
rect.ul_y = (short) y;
rect.lr_x = (short) (x + width - 1);
rect.lr_y = (short) (y + height - 1);
OS.PtSetAreaFromWidgetCanvas (scrolledHandle != 0 ? scrolledHandle : handle, rect, area);
if (horizontalBar != null) {
Point size = horizontalBar.getSize ();
area.size_h += size.y;
}
if (verticalBar != null) {
Point size = verticalBar.getSize ();
area.size_w += size.x;
}
return new Rectangle (area.pos_x, area.pos_y, area.size_w, area.size_h);
}
/**
* 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();
PhRect_t rect = new PhRect_t ();
int validParent = OS.PtValidParent (handle, OS.PtContainer ());
if (!OS.PtWidgetIsRealized (handle)) OS.PtExtentWidgetFamily (handle);
OS.PtCalcCanvas (validParent, rect);
int width = rect.lr_x - rect.ul_x + 1;
int height = rect.lr_y - rect.ul_y + 1;
return new Rectangle (0, 0, 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 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;
}
boolean isTabGroup () {
if ((state & CANVAS) != 0) return true;
return super.isTabGroup ();
}
void releaseHandle () {
super.releaseHandle ();
scrolledHandle = 0;
}
void resizeClientArea () {
/* Do nothing */
}
void reskinChildren (int flags) {
if (horizontalBar != null) horizontalBar.reskin (flags);
if (verticalBar != null) verticalBar.reskin (flags);
super.reskinChildren (flags);
}
void releaseChildren (boolean destroy) {
if (horizontalBar != null) {
horizontalBar.release (false);
horizontalBar = null;
}
if (verticalBar != null) {
verticalBar.release (false);
verticalBar = null;
}
super.releaseChildren (destroy);
}
void register () {
super.register ();
if (scrolledHandle != 0) WidgetTable.put (scrolledHandle, this);
}
int topHandle () {
if (scrolledHandle == 0) return handle;
return scrolledHandle;
}
}