/*******************************************************************************
* Copyright (c) 2000, 2008, 2012 IBM Corporation, Gerhardt Informatics Kft. 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
* Gerhardt Informatics Kft. - GEFGWT port
*******************************************************************************/
package org.eclipse.swt.custom;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Layout;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.ScrollBar;
import org.eclipse.swt.widgets.Shell;
import com.google.gwt.user.client.ui.LayoutPanel;
/**
* A ScrolledComposite provides scrollbars and will scroll its content when the
* user uses the scrollbars.
*
*
* <p>
* There are two ways to use the ScrolledComposite:
*
* <p>
* 1) Set the size of the control that is being scrolled and the
* ScrolledComposite will show scrollbars when the contained control can not be
* fully seen.
*
* 2) The second way imitates the way a browser would work. Set the minimum size
* of the control and the ScrolledComposite will show scroll bars if the visible
* area is less than the minimum size of the control and it will expand the size
* of the control if the visible area is greater than the minimum size. This
* requires invoking both setMinWidth(), setMinHeight() and
* setExpandHorizontal(), setExpandVertical().
*
* <code><pre>
* public static void main (String [] args) {
* Display display = new Display ();
* Color red = display.getSystemColor(SWT.COLOR_RED);
* Color blue = display.getSystemColor(SWT.COLOR_BLUE);
* Shell shell = new Shell (display);
* shell.setLayout(new FillLayout());
*
* // set the size of the scrolled content - method 1
* final ScrolledComposite sc1 = new ScrolledComposite(shell, SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
* final Composite c1 = new Composite(sc1, SWT.NONE);
* sc1.setContent(c1);
* c1.setBackground(red);
* GridLayout layout = new GridLayout();
* layout.numColumns = 4;
* c1.setLayout(layout);
* Button b1 = new Button (c1, SWT.PUSH);
* b1.setText("first button");
* c1.setSize(c1.computeSize(SWT.DEFAULT, SWT.DEFAULT));
*
* // set the minimum width and height of the scrolled content - method 2
* final ScrolledComposite sc2 = new ScrolledComposite(shell, SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
* sc2.setExpandHorizontal(true);
* sc2.setExpandVertical(true);
* final Composite c2 = new Composite(sc2, SWT.NONE);
* sc2.setContent(c2);
* c2.setBackground(blue);
* layout = new GridLayout();
* layout.numColumns = 4;
* c2.setLayout(layout);
* Button b2 = new Button (c2, SWT.PUSH);
* b2.setText("first button");
* sc2.setMinSize(c2.computeSize(SWT.DEFAULT, SWT.DEFAULT));
*
* Button add = new Button (shell, SWT.PUSH);
* add.setText("add children");
* final int[] index = new int[]{0};
* add.addListener(SWT.Selection, new Listener() {
* public void handleEvent(Event e) {
* index[0]++;
* Button button = new Button(c1, SWT.PUSH);
* button.setText("button "+index[0]);
* // reset size of content so children can be seen - method 1
* c1.setSize(c1.computeSize(SWT.DEFAULT, SWT.DEFAULT));
* c1.layout();
*
* button = new Button(c2, SWT.PUSH);
* button.setText("button "+index[0]);
* // reset the minimum width and height so children can be seen - method 2
* sc2.setMinSize(c2.computeSize(SWT.DEFAULT, SWT.DEFAULT));
* c2.layout();
* }
* });
*
* shell.open ();
* while (!shell.isDisposed ()) {
* if (!display.readAndDispatch ()) display.sleep ();
* }
* display.dispose ();
* }
* </pre></code>
*
* <dl>
* <dt><b>Styles:</b>
* <dd>H_SCROLL, V_SCROLL
* </dl>
*
* @see <a
* href="http://www.eclipse.org/swt/snippets/#scrolledcomposite">ScrolledComposite
* snippets</a>
* @see <a href="http://www.eclipse.org/swt/">Sample code and further
* information</a>
*/
public class ScrolledComposite extends Composite {
Control content;
Listener contentListener;
Listener filter;
int minHeight = 0;
int minWidth = 0;
boolean expandHorizontal = false;
boolean expandVertical = false;
boolean alwaysShowScroll = false;
boolean showFocusedControl = false;
/**
* 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 widget which will be the parent of the new instance (cannot
* be null)
* @param style
* the style of widget 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>
* </ul>
*
* @see SWT#H_SCROLL
* @see SWT#V_SCROLL
* @see #getStyle()
*/
public ScrolledComposite(Composite parent, int style) {
super(new LayoutPanel(), parent, style);
}
static int checkStyle(int style) {
int mask = SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER | SWT.LEFT_TO_RIGHT
| SWT.RIGHT_TO_LEFT;
return style & mask;
}
boolean contains(Control control) {
if (control == null || control.isDisposed())
return false;
Composite parent = control.getParent();
while (parent != null && !(parent instanceof Shell)) {
if (this == parent)
return true;
parent = parent.getParent();
}
return false;
}
/**
* Returns the Always Show Scrollbars flag. True if the scrollbars are
* always shown even if they are not required. False if the scrollbars are
* only visible when some part of the composite needs to be scrolled to be
* seen. The H_SCROLL and V_SCROLL style bits are also required to enable
* scrollbars in the horizontal and vertical directions.
*
* @return the Always Show Scrollbars flag value
*/
public boolean getAlwaysShowScrollBars() {
// checkWidget();
return alwaysShowScroll;
}
/**
* Returns <code>true</code> if the content control will be expanded to fill
* available horizontal space.
*
* @return the receiver's horizontal expansion 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>
*
* @since 3.2
*/
public boolean getExpandHorizontal() {
checkWidget();
return expandHorizontal;
}
/**
* Returns <code>true</code> if the content control will be expanded to fill
* available vertical space.
*
* @return the receiver's vertical expansion 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>
*
* @since 3.2
*/
public boolean getExpandVertical() {
checkWidget();
return expandVertical;
}
/**
* Returns the minimum width of the content control.
*
* @return the minimum width
*
* @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 int getMinWidth() {
checkWidget();
return minWidth;
}
/**
* Returns the minimum height of the content control.
*
* @return the minimum height
*
* @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 int getMinHeight() {
checkWidget();
return minHeight;
}
/**
* Get the content that is being scrolled.
*
* @return the control displayed in the content area
*/
public Control getContent() {
// checkWidget();
return content;
}
/**
* Returns <code>true</code> if the receiver automatically scrolls to a
* focused child control to make it visible. Otherwise, returns
* <code>false</code>.
*
* @return a boolean indicating whether focused child controls are
* automatically scrolled into the viewport
*
* @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 boolean getShowFocusedControl() {
checkWidget();
return showFocusedControl;
}
void hScroll() {
if (content == null)
return;
Point location = content.getLocation();
ScrollBar hBar = getHorizontalBar();
int hSelection = hBar.getSelection();
content.setLocation(-hSelection, location.y);
}
boolean needHScroll(Rectangle contentRect, boolean vVisible) {
ScrollBar hBar = getHorizontalBar();
if (hBar == null)
return false;
Rectangle hostRect = getBounds();
int border = getBorderWidth();
hostRect.width -= 2 * border;
ScrollBar vBar = getVerticalBar();
if (vVisible && vBar != null)
hostRect.width -= vBar.getSize().x;
if (!expandHorizontal && contentRect.width > hostRect.width)
return true;
if (expandHorizontal && minWidth > hostRect.width)
return true;
return false;
}
boolean needVScroll(Rectangle contentRect, boolean hVisible) {
ScrollBar vBar = getVerticalBar();
if (vBar == null)
return false;
Rectangle hostRect = getBounds();
int border = getBorderWidth();
hostRect.height -= 2 * border;
ScrollBar hBar = getHorizontalBar();
if (hVisible && hBar != null)
hostRect.height -= hBar.getSize().y;
if (!expandVertical && contentRect.height > hostRect.height)
return true;
if (expandVertical && minHeight > hostRect.height)
return true;
return false;
}
/**
* Return the point in the content that currently appears in the top left
* corner of the scrolled composite.
*
* @return the point in the content that currently appears in the top left
* corner of the scrolled composite. If no content has been set,
* this returns (0, 0).
*
* @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 2.0
*/
public Point getOrigin() {
checkWidget();
if (content == null)
return new Point(0, 0);
Point location = content.getLocation();
return new Point(-location.x, -location.y);
}
/**
* Scrolls the content so that the specified point in the content is in the
* top left corner. If no content has been set, nothing will occur.
*
* Negative values will be ignored. Values greater than the maximum scroll
* distance will result in scrolling to the end of the scrollbar.
*
* @param origin
* the point on the content to appear in the top left corner
*
* @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>
* <li>ERROR_INVALID_ARGUMENT - value of origin is outside of
* content
* </ul>
* @since 2.0
*/
public void setOrigin(Point origin) {
setOrigin(origin.x, origin.y);
}
/**
* Scrolls the content so that the specified point in the content is in the
* top left corner. If no content has been set, nothing will occur.
*
* Negative values will be ignored. Values greater than the maximum scroll
* distance will result in scrolling to the end of the scrollbar.
*
* @param x
* the x coordinate of the content to appear in the top left
* corner
*
* @param y
* the y coordinate of the content to appear in the top left
* corner
*
* @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 2.0
*/
public void setOrigin(int x, int y) {
checkWidget();
if (content == null)
return;
ScrollBar hBar = getHorizontalBar();
if (hBar != null) {
hBar.setSelection(x);
x = -hBar.getSelection();
} else {
x = 0;
}
ScrollBar vBar = getVerticalBar();
if (vBar != null) {
vBar.setSelection(y);
y = -vBar.getSelection();
} else {
y = 0;
}
content.setLocation(x, y);
}
/**
* Set the Always Show Scrollbars flag. True if the scrollbars are always
* shown even if they are not required. False if the scrollbars are only
* visible when some part of the composite needs to be scrolled to be seen.
* The H_SCROLL and V_SCROLL style bits are also required to enable
* scrollbars in the horizontal and vertical directions.
*
* @param show
* true to show the scrollbars even when not required, false to
* show scrollbars only when required
*
* @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 setAlwaysShowScrollBars(boolean show) {
}
/**
* Set the content that will be scrolled.
*
* @param content
* the control to be displayed in the content 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>
*/
public void setContent(Control content) {
checkWidget();
if (this.content != null && !this.content.isDisposed()) {
this.content.removeListener(SWT.Resize, contentListener);
this.content.setBounds(new Rectangle(-200, -200, 0, 0));
}
this.content = content;
ScrollBar vBar = getVerticalBar();
ScrollBar hBar = getHorizontalBar();
if (this.content != null) {
if (vBar != null) {
vBar.setMaximum(0);
vBar.setThumb(0);
vBar.setSelection(0);
}
if (hBar != null) {
hBar.setMaximum(0);
hBar.setThumb(0);
hBar.setSelection(0);
}
content.setLocation(0, 0);
layout(false);
this.content.addListener(SWT.Resize, contentListener);
} else {
if (hBar != null)
hBar.setVisible(alwaysShowScroll);
if (vBar != null)
vBar.setVisible(alwaysShowScroll);
}
}
/**
* Configure the ScrolledComposite to resize the content object to be as
* wide as the ScrolledComposite when the width of the ScrolledComposite is
* greater than the minimum width specified in setMinWidth. If the
* ScrolledComposite is less than the minimum width, the content will not be
* resized and instead the horizontal scroll bar will be used to view the
* entire width. If expand is false, this behaviour is turned off. By
* default, this behaviour is turned off.
*
* @param expand
* true to expand the content control to fill available
* horizontal space
*
* @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 setExpandHorizontal(boolean expand) {
checkWidget();
if (expand == expandHorizontal)
return;
expandHorizontal = expand;
layout(false);
}
/**
* Configure the ScrolledComposite to resize the content object to be as
* tall as the ScrolledComposite when the height of the ScrolledComposite is
* greater than the minimum height specified in setMinHeight. If the
* ScrolledComposite is less than the minimum height, the content will not
* be resized and instead the vertical scroll bar will be used to view the
* entire height. If expand is false, this behaviour is turned off. By
* default, this behaviour is turned off.
*
* @param expand
* true to expand the content control to fill available vertical
* space
*
* @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 setExpandVertical(boolean expand) {
checkWidget();
if (expand == expandVertical)
return;
expandVertical = expand;
layout(false);
}
/**
* Sets the layout which is associated with the receiver to be the argument
* which may be null.
* <p>
* Note: No Layout can be set on this Control because it already manages the
* size and position of its children.
* </p>
*
* @param layout
* the receiver's new layout 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 void setLayout(Layout layout) {
checkWidget();
return;
}
/**
* Specify the minimum height at which the ScrolledComposite will begin
* scrolling the content with the vertical scroll bar. This value is only
* relevant if setExpandVertical(true) has been set.
*
* @param height
* the minimum height or 0 for default height
*
* @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 setMinHeight(int height) {
setMinSize(minWidth, height);
}
/**
* Specify the minimum width and height at which the ScrolledComposite will
* begin scrolling the content with the horizontal scroll bar. This value is
* only relevant if setExpandHorizontal(true) and setExpandVertical(true)
* have been set.
*
* @param size
* the minimum size or null for the default 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 void setMinSize(Point size) {
if (size == null) {
setMinSize(0, 0);
} else {
setMinSize(size.x, size.y);
}
}
/**
* Specify the minimum width and height at which the ScrolledComposite will
* begin scrolling the content with the horizontal scroll bar. This value is
* only relevant if setExpandHorizontal(true) and setExpandVertical(true)
* have been set.
*
* @param width
* the minimum width or 0 for default width
* @param height
* the minimum height or 0 for default height
*
* @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 setMinSize(int width, int height) {
checkWidget();
if (width == minWidth && height == minHeight)
return;
minWidth = Math.max(0, width);
minHeight = Math.max(0, height);
layout(false);
}
/**
* Specify the minimum width at which the ScrolledComposite will begin
* scrolling the content with the horizontal scroll bar. This value is only
* relevant if setExpandHorizontal(true) has been set.
*
* @param width
* the minimum width or 0 for default width
*
* @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 setMinWidth(int width) {
setMinSize(width, minHeight);
}
/**
* Configure the receiver to automatically scroll to a focused child control
* to make it visible.
*
* If show is <code>false</code>, show a focused control is off. By default,
* show a focused control is off.
*
* @param show
* <code>true</code> to show a focused control.
*
* @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 void setShowFocusedControl(boolean show) {
checkWidget();
if (showFocusedControl == show)
return;
Display display = getDisplay();
display.removeFilter(SWT.FocusIn, filter);
showFocusedControl = show;
if (!showFocusedControl)
return;
display.addFilter(SWT.FocusIn, filter);
Control control = display.getFocusControl();
if (contains(control))
showControl(control);
}
/**
* Scrolls the content of the receiver so that the control is visible.
*
* @param control
* the control to be shown
*
* @exception IllegalArgumentException
* <ul>
* <li>ERROR_NULL_ARGUMENT - if the control is null</li>
* <li>ERROR_INVALID_ARGUMENT - if the control has been
* disposed</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>
*
* @since 3.4
*/
public void showControl(Control control) {
checkWidget();
if (control == null)
SWT.error(SWT.ERROR_NULL_ARGUMENT);
if (control.isDisposed())
SWT.error(SWT.ERROR_INVALID_ARGUMENT);
if (!contains(control))
SWT.error(SWT.ERROR_INVALID_ARGUMENT);
Rectangle itemRect = getDisplay().map(control.getParent(), this,
control.getBounds());
Rectangle area = getClientArea();
Point origin = getOrigin();
if (itemRect.x < 0) {
origin.x = Math.max(0, origin.x + itemRect.x);
} else {
if (area.width < itemRect.x + itemRect.width)
origin.x = Math.max(
0,
origin.x + itemRect.x
+ Math.min(itemRect.width, area.width)
- area.width);
}
if (itemRect.y < 0) {
origin.y = Math.max(0, origin.y + itemRect.y);
} else {
if (area.height < itemRect.y + itemRect.height)
origin.y = Math.max(
0,
origin.y + itemRect.y
+ Math.min(itemRect.height, area.height)
- area.height);
}
setOrigin(origin);
}
void vScroll() {
if (content == null)
return;
Point location = content.getLocation();
ScrollBar vBar = getVerticalBar();
int vSelection = vBar.getSelection();
content.setLocation(location.x, -vSelection);
}
}