/*******************************************************************************
* Copyright (c) 2000, 2009 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.draw2d;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.draw2d.geometry.Dimension;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.draw2d.geometry.Rectangle;
/**
* A scrolling Canvas that contains {@link Figure Figures}
* viewed through a {@link Viewport}. Call {@link #setContents(IFigure)}
* to specify the root of the tree of <tt>Figures</tt> to be viewed
* through the <tt>Viewport</tt>.
* <p>
* Normal procedure for using a FigureCanvas:
* <ol>
* <li>Create a FigureCanvas.
* <li>Create a Draw2d Figure and call {@link #setContents(IFigure)}. This Figure will be the
* top-level Figure of the Draw2d application.
* </ol>
* <dl>
* <dt><b>Required Styles (when using certain constructors):</b></dt>
* <dd>V_SCROLL, H_SCROLL, NO_REDRAW_RESIZE</dd>
* <dt><b>Optional Styles:</b></dt>
* <dd>DOUBLE_BUFFERED, RIGHT_TO_LEFT, LEFT_TO_RIGHT, NO_BACKGROUND, BORDER</dd>
* </dl>
* <p>
* Note: Only one of the styles RIGHT_TO_LEFT, LEFT_TO_RIGHT may be specified.
* </p>
*/
public class FigureCanvas
extends Canvas
{
private static final int ACCEPTED_STYLES =
SWT.RIGHT_TO_LEFT | SWT.LEFT_TO_RIGHT
| SWT.V_SCROLL | SWT.H_SCROLL
| SWT.NO_BACKGROUND
| SWT.NO_REDRAW_RESIZE
| SWT.DOUBLE_BUFFERED
| SWT.BORDER;
/**
* The default styles are mixed in when certain constructors are used. This
* constant is a bitwise OR of the following SWT style constants:
* <UL>
* <LI>{@link SWT#NO_REDRAW_RESIZE}</LI>
* <LI>{@link SWT#NO_BACKGROUND}</LI>
* <LI>{@link SWT#V_SCROLL}</LI>
* <LI>{@link SWT#H_SCROLL}</LI>
* </UL>
*/
static final int DEFAULT_STYLES =
SWT.NO_REDRAW_RESIZE
| SWT.NO_BACKGROUND
| SWT.V_SCROLL
| SWT.H_SCROLL;
private static final int REQUIRED_STYLES =
SWT.NO_REDRAW_RESIZE
| SWT.V_SCROLL
| SWT.H_SCROLL;
/** Never show scrollbar */
public static int NEVER = 0;
/** Automatically show scrollbar when needed */
public static int AUTOMATIC = 1;
/** Always show scrollbar */
public static int ALWAYS = 2;
private int vBarVisibility = AUTOMATIC;
private int hBarVisibility = AUTOMATIC;
private Viewport viewport;
private Font font;
private int hBarOffset;
private int vBarOffset;
private PropertyChangeListener horizontalChangeListener = new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent event) {
RangeModel model = getViewport().getHorizontalRangeModel();
hBarOffset = Math.max(0, -model.getMinimum());
getHorizontalBar().setValues(
model.getValue() + hBarOffset,
model.getMinimum() + hBarOffset,
model.getMaximum() + hBarOffset,
model.getExtent(),
Math.max(1, model.getExtent() / 20),
Math.max(1, model.getExtent() * 3 / 4));
}
};
private PropertyChangeListener verticalChangeListener = new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent event) {
RangeModel model = getViewport().getVerticalRangeModel();
vBarOffset = Math.max(0, -model.getMinimum());
getVerticalBar().setValues(
model.getValue() + vBarOffset,
model.getMinimum() + vBarOffset,
model.getMaximum() + vBarOffset,
model.getExtent(),
Math.max(1, model.getExtent() / 20),
Math.max(1, model.getExtent() * 3 / 4));
}
};
private final LightweightSystem lws;
/**
* Creates a new FigureCanvas with the given parent and the {@link #DEFAULT_STYLES}.
*
* @param parent the parent
*/
public FigureCanvas(Composite parent) {
this(parent, SWT.DOUBLE_BUFFERED, new LightweightSystem());
}
/**
* Constructor which applies the default styles plus any optional styles indicated.
* @param parent the parent composite
* @param style see the class javadoc for optional styles
* @since 3.1
*/
public FigureCanvas(Composite parent, int style) {
this(parent, style, new LightweightSystem());
}
/**
* Constructor which uses the given styles verbatim. Certain styles must be used
* with this class. Refer to the class javadoc for more details.
* @param style see the class javadoc for <b>required</b> and optional styles
* @param parent the parent composite
* @since 3.4
*/
public FigureCanvas(int style, Composite parent) {
this(style, parent, new LightweightSystem());
}
/**
* Constructs a new FigureCanvas with the given parent and LightweightSystem, using
* the {@link #DEFAULT_STYLES}.
* @param parent the parent
* @param lws the LightweightSystem
*/
public FigureCanvas(Composite parent, LightweightSystem lws) {
this(parent, SWT.DOUBLE_BUFFERED, lws);
}
/**
* Constructor taking a lightweight system and SWT style, which is used verbatim.
* Certain styles must be used with this class. Refer to the class javadoc for
* more details.
* @param style see the class javadoc for <b>required</b> and optional styles
* @param parent the parent composite
* @param lws the LightweightSystem
* @since 3.4
*/
public FigureCanvas(int style, Composite parent, LightweightSystem lws) {
super(parent, checkStyle(style));
getHorizontalBar().setVisible(false);
getVerticalBar().setVisible(false);
this.lws = lws;
lws.setControl(this);
hook();
}
/**
* Constructor
* @param parent the parent composite
* @param style look at class javadoc for valid styles
* @param lws the lightweight system
* @since 3.1
*/
public FigureCanvas(Composite parent, int style, LightweightSystem lws) {
this(style | DEFAULT_STYLES, parent, lws);
}
private static int checkStyle(int style) {
if ((style & REQUIRED_STYLES) != REQUIRED_STYLES)
throw new IllegalArgumentException("Required style missing on FigureCanvas"); //$NON-NLS-1$
if ((style & ~ACCEPTED_STYLES) != 0)
throw new IllegalArgumentException("Invalid style being set on FigureCanvas"); //$NON-NLS-1$
return style;
}
/**
* @see org.eclipse.swt.widgets.Composite#computeSize(int, int, boolean)
*/
public org.eclipse.swt.graphics.Point computeSize(int wHint, int hHint, boolean changed) {
// TODO Still doesn't handle scrollbar cases, such as when a constrained width
// would require a horizontal scrollbar, and therefore additional height.
int borderSize = computeTrim(0, 0, 0, 0).x * -2;
if (wHint >= 0)
wHint = Math.max(0, wHint - borderSize);
if (hHint >= 0)
hHint = Math.max(0, hHint - borderSize);
Dimension size = getLightweightSystem()
.getRootFigure()
.getPreferredSize(wHint, hHint)
.getExpanded(borderSize, borderSize);
size.union(new Dimension(wHint, hHint));
return new org.eclipse.swt.graphics.Point(size.width, size.height);
}
/**
* @return the contents of the {@link Viewport}.
*/
public IFigure getContents() {
return getViewport().getContents();
}
/**
* @see org.eclipse.swt.widgets.Control#getFont()
*/
public Font getFont() {
if (font == null)
font = super.getFont();
return font;
}
/**
* @return the horizontal scrollbar visibility.
*/
public int getHorizontalScrollBarVisibility() {
return hBarVisibility;
}
/**
* @return the LightweightSystem
*/
public LightweightSystem getLightweightSystem() {
return lws;
}
/**
* @return the vertical scrollbar visibility.
*/
public int getVerticalScrollBarVisibility() {
return vBarVisibility;
}
/**
* Returns the Viewport. If it's <code>null</code>, a new one is created.
* @return the viewport
*/
public Viewport getViewport() {
if (viewport == null)
setViewport(new Viewport(true));
return viewport;
}
/**
* Adds listeners for scrolling.
*/
private void hook() {
getLightweightSystem().getUpdateManager().addUpdateListener(new UpdateListener() {
public void notifyPainting(Rectangle damage, java.util.Map dirtyRegions) { }
public void notifyValidating() {
if (!isDisposed())
layoutViewport();
}
});
getHorizontalBar().addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent event) {
scrollToX(getHorizontalBar().getSelection() - hBarOffset);
}
});
getVerticalBar().addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent event) {
scrollToY(getVerticalBar().getSelection() - vBarOffset);
}
});
}
private void hookViewport() {
getViewport()
.getHorizontalRangeModel()
.addPropertyChangeListener(horizontalChangeListener);
getViewport()
.getVerticalRangeModel()
.addPropertyChangeListener(verticalChangeListener);
}
private void unhookViewport() {
getViewport()
.getHorizontalRangeModel()
.removePropertyChangeListener(horizontalChangeListener);
getViewport()
.getVerticalRangeModel()
.removePropertyChangeListener(verticalChangeListener);
}
private void layoutViewport() {
ScrollPaneSolver.Result result;
result = ScrollPaneSolver.solve(new Rectangle(getBounds()).setLocation(0, 0),
getViewport(),
getHorizontalScrollBarVisibility(),
getVerticalScrollBarVisibility(),
computeTrim(0, 0, 0, 0).width,
computeTrim(0, 0, 0, 0).height);
getLightweightSystem().setIgnoreResize(true);
try {
if (getHorizontalBar().getVisible() != result.showH)
getHorizontalBar().setVisible(result.showH);
if (getVerticalBar().getVisible() != result.showV)
getVerticalBar().setVisible(result.showV);
Rectangle r = new Rectangle(getClientArea());
r.setLocation(0, 0);
getLightweightSystem().getRootFigure().setBounds(r);
} finally {
getLightweightSystem().setIgnoreResize(false);
}
}
/**
* Scrolls in an animated way to the new x and y location.
* @param x the x coordinate to scroll to
* @param y the y coordinate to scroll to
*/
public void scrollSmoothTo(int x, int y) {
// Ensure newHOffset and newVOffset are within the appropriate ranges
x = verifyScrollBarOffset(getViewport().getHorizontalRangeModel(), x);
y = verifyScrollBarOffset(getViewport().getVerticalRangeModel(), y);
int oldX = getViewport().getViewLocation().x;
int oldY = getViewport().getViewLocation().y;
int dx = x - oldX;
int dy = y - oldY;
if (dx == 0 && dy == 0)
return; //Nothing to do.
Dimension viewingArea = getViewport().getClientArea().getSize();
int minFrames = 3;
int maxFrames = 6;
if (dx == 0 || dy == 0) {
minFrames = 6;
maxFrames = 13;
}
int frames = (Math.abs(dx) + Math.abs(dy)) / 15;
frames = Math.max(frames, minFrames);
frames = Math.min(frames, maxFrames);
int stepX = Math.min((dx / frames), (viewingArea.width / 3));
int stepY = Math.min((dy / frames), (viewingArea.height / 3));
for (int i = 1; i < frames; i++) {
scrollTo(oldX + i * stepX, oldY + i * stepY);
getViewport().getUpdateManager().performUpdate();
}
scrollTo(x, y);
}
/**
* Scrolls the contents to the new x and y location. If this scroll operation only
* consists of a vertical or horizontal scroll, a call will be made to
* {@link #scrollToY(int)} or {@link #scrollToX(int)}, respectively, to increase
* performance.
*
* @param x the x coordinate to scroll to
* @param y the y coordinate to scroll to
*/
public void scrollTo(int x, int y) {
x = verifyScrollBarOffset(getViewport().getHorizontalRangeModel(), x);
y = verifyScrollBarOffset(getViewport().getVerticalRangeModel(), y);
if (x == getViewport().getViewLocation().x)
scrollToY(y);
else if (y == getViewport().getViewLocation().y)
scrollToX(x);
else
getViewport().setViewLocation(x, y);
}
/**
* Scrolls the contents horizontally so that they are offset by <code>hOffset</code>.
*
* @param hOffset the new horizontal offset
*/
public void scrollToX(int hOffset) {
hOffset = verifyScrollBarOffset(getViewport().getHorizontalRangeModel(), hOffset);
int hOffsetOld = getViewport().getViewLocation().x;
if (hOffset == hOffsetOld)
return;
int dx = -hOffset + hOffsetOld;
Rectangle clientArea = getViewport().getBounds().getCropped(getViewport().getInsets());
Rectangle blit = clientArea.getResized(-Math.abs(dx), 0);
Rectangle expose = clientArea.getCopy();
Point dest = clientArea.getTopLeft();
expose.width = Math.abs(dx);
if (dx < 0) { //Moving left?
blit.translate(-dx, 0); //Move blit area to the right
expose.x = dest.x + blit.width;
} else //Moving right
dest.x += dx; //Move expose area to the right
// fix for bug 41111
Control[] children = getChildren();
boolean[] manualMove = new boolean[children.length];
for (int i = 0; i < children.length; i++) {
org.eclipse.swt.graphics.Rectangle bounds = children[i].getBounds();
manualMove[i] = blit.width <= 0 || bounds.x > blit.x + blit.width
|| bounds.y > blit.y + blit.height || bounds.x + bounds.width < blit.x
|| bounds.y + bounds.height < blit.y;
}
scroll(dest.x, dest.y, blit.x, blit.y, blit.width, blit.height, true);
for (int i = 0; i < children.length; i++) {
if (children[i].isDisposed ())
continue;
org.eclipse.swt.graphics.Rectangle bounds = children[i].getBounds();
if (manualMove[i])
children[i].setBounds(bounds.x + dx, bounds.y, bounds.width, bounds.height);
}
getViewport().setIgnoreScroll(true);
getViewport().setHorizontalLocation(hOffset);
getViewport().setIgnoreScroll(false);
redraw(expose.x, expose.y, expose.width, expose.height, true);
}
/**
* Scrolls the contents vertically so that they are offset by <code>vOffset</code>.
*
* @param vOffset the new vertical offset
*/
public void scrollToY(int vOffset) {
vOffset = verifyScrollBarOffset(getViewport().getVerticalRangeModel(), vOffset);
int vOffsetOld = getViewport().getViewLocation().y;
if (vOffset == vOffsetOld)
return;
int dy = -vOffset + vOffsetOld;
Rectangle clientArea = getViewport().getBounds().getCropped(getViewport().getInsets());
Rectangle blit = clientArea.getResized(0, -Math.abs(dy));
Rectangle expose = clientArea.getCopy();
Point dest = clientArea.getTopLeft();
expose.height = Math.abs(dy);
if (dy < 0) { //Moving up?
blit.translate(0, -dy); //Move blit area down
expose.y = dest.y + blit.height; //Move expose area down
} else //Moving down
dest.y += dy;
// fix for bug 41111
Control[] children = getChildren();
boolean[] manualMove = new boolean[children.length];
for (int i = 0; i < children.length; i++) {
org.eclipse.swt.graphics.Rectangle bounds = children[i].getBounds();
manualMove[i] = blit.height <= 0 || bounds.x > blit.x + blit.width
|| bounds.y > blit.y + blit.height || bounds.x + bounds.width < blit.x
|| bounds.y + bounds.height < blit.y;
}
scroll(dest.x, dest.y, blit.x, blit.y, blit.width, blit.height, true);
for (int i = 0; i < children.length; i++) {
if (children[i].isDisposed ())
continue;
org.eclipse.swt.graphics.Rectangle bounds = children[i].getBounds();
if (manualMove[i])
children[i].setBounds(bounds.x, bounds.y + dy, bounds.width, bounds.height);
}
getViewport().setIgnoreScroll(true);
getViewport().setVerticalLocation(vOffset);
getViewport().setIgnoreScroll(false);
redraw(expose.x, expose.y, expose.width, expose.height, true);
}
/**
* Sets the given border on the LightweightSystem's root figure.
*
* @param border The new border
*/
public void setBorder(Border border) {
getLightweightSystem().getRootFigure().setBorder(border);
}
/**
* Sets the contents of the {@link Viewport}.
*
* @param figure the new contents
*/
public void setContents(IFigure figure) {
getViewport().setContents(figure);
}
/**
* @see org.eclipse.swt.widgets.Control#setFont(org.eclipse.swt.graphics.Font)
*/
public void setFont(Font font) {
this.font = font;
super.setFont(font);
}
/**
* Sets the horizontal scrollbar visibility. Possible values are {@link #AUTOMATIC},
* {@link #ALWAYS}, and {@link #NEVER}.
*
* @param v the new visibility
*/
public void setHorizontalScrollBarVisibility(int v) {
hBarVisibility = v;
}
/**
* Sets both the horizontal and vertical scrollbar visibility to the given value.
* Possible values are {@link #AUTOMATIC}, {@link #ALWAYS}, and {@link #NEVER}.
* @param both the new visibility
*/
public void setScrollBarVisibility(int both) {
setHorizontalScrollBarVisibility(both);
setVerticalScrollBarVisibility(both);
}
/**
* Sets the vertical scrollbar visibility. Possible values are {@link #AUTOMATIC},
* {@link #ALWAYS}, and {@link #NEVER}.
*
* @param v the new visibility
*/
public void setVerticalScrollBarVisibility(int v) {
vBarVisibility = v;
}
/**
* Sets the Viewport. The given Viewport must use "fake" scrolling. That is, it must be
* constructed using <code>new Viewport(true)</code>.
*
* @param vp the new viewport
*/
public void setViewport(Viewport vp) {
if (viewport != null)
unhookViewport();
viewport = vp;
lws.setContents(viewport);
hookViewport();
}
private int verifyScrollBarOffset(RangeModel model, int value) {
value = Math.max(model.getMinimum(), value);
return Math.min(model.getMaximum() - model.getExtent(), value);
}
}