/*******************************************************************************
* 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.swt.widgets;
import org.eclipse.swt.internal.carbon.*;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
/**
* Instances of this class provide a surface for drawing
* arbitrary graphics.
* <dl>
* <dt><b>Styles:</b></dt>
* <dd>(none)</dd>
* <dt><b>Events:</b></dt>
* <dd>(none)</dd>
* </dl>
* <p>
* This class may be subclassed by custom control implementors
* who are building controls that are <em>not</em> constructed
* from aggregates of other controls. That is, they are either
* painted using SWT graphics calls or are handled by native
* methods.
* </p>
*
* @see Composite
* @see <a href="http://www.eclipse.org/swt/snippets/#canvas">Canvas snippets</a>
* @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a>
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
*/
public class Canvas extends Composite {
Caret caret;
IME ime;
Canvas () {
/* 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>
* </ul>
*
* @see SWT
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public Canvas (Composite parent, int style) {
super (parent, style);
}
/**
* Fills the interior of the rectangle specified by the arguments,
* with the receiver's background.
*
* @param gc the gc where the rectangle is to be filled
* @param x the x coordinate of the rectangle to be filled
* @param y the y coordinate of the rectangle to be filled
* @param width the width of the rectangle to be filled
* @param height the height of the rectangle to be filled
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the gc is null</li>
* <li>ERROR_INVALID_ARGUMENT - if the gc 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 3.2
*/
public void drawBackground (GC gc, int x, int y, int width, int height) {
super.drawBackground(gc, x, y, width, height, 0, 0);
}
void drawWidget (int control, int context, int damageRgn, int visibleRgn, int theEvent) {
super.drawWidget (control, context, damageRgn, visibleRgn, theEvent);
if (OS.VERSION >= 0x1040) {
if (control != handle) return;
if (caret == null) return;
if (caret.isShowing) {
OS.CGContextSaveGState (context);
CGRect rect = new CGRect ();
rect.x = caret.x;
rect.y = caret.y;
Image image = caret.image;
OS.CGContextSetBlendMode (context, OS.kCGBlendModeDifference);
if (image != null) {
rect.width = OS.CGImageGetWidth (image.handle);
rect.height = OS.CGImageGetHeight (image.handle);
OS.CGContextScaleCTM (context, 1, -1);
OS.CGContextTranslateCTM (context, 0, -(rect.height + 2 * rect.y));
OS.CGContextDrawImage (context, rect, image.handle);
} else {
rect.width = caret.width != 0 ? caret.width : Caret.DEFAULT_WIDTH;
rect.height = caret.height;
OS.CGContextSetShouldAntialias (context, false);
int colorspace = OS.CGColorSpaceCreateDeviceRGB ();
OS.CGContextSetFillColorSpace (context, colorspace);
OS.CGContextSetFillColor (context, new float[]{1, 1, 1, 1});
OS.CGColorSpaceRelease (colorspace);
OS.CGContextFillRect (context, rect);
}
OS.CGContextRestoreGState (context);
}
}
}
/**
* Returns the caret.
* <p>
* The caret for the control is automatically hidden
* and shown when the control is painted or resized,
* when focus is gained or lost and when an the control
* is scrolled. To avoid drawing on top of the caret,
* the programmer must hide and show the caret when
* drawing in the window any other time.
* </p>
*
* @return the caret for the receiver, may be 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 Caret getCaret () {
checkWidget();
return caret;
}
/**
* Returns the IME.
*
* @return the IME
*
* @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 IME getIME () {
checkWidget();
return ime;
}
int kEventControlDraw (int nextHandler, int theEvent, int userData) {
int [] theControl = new int [1];
OS.GetEventParameter (theEvent, OS.kEventParamDirectObject, OS.typeControlRef, null, 4, null, theControl);
boolean isFocus = OS.VERSION < 0x1040 && theControl [0] == handle && caret != null && caret.isFocusCaret ();
if (isFocus) caret.killFocus ();
int result = super.kEventControlDraw (nextHandler, theEvent, userData);
if (isFocus) caret.setFocus ();
return result;
}
int kEventControlSetFocusPart (int nextHandler, int theEvent, int userData) {
int result = super.kEventControlSetFocusPart (nextHandler, theEvent, userData);
if (result == OS.noErr) {
if (!isDisposed ()) {
Shell shell = getShell ();
short [] part = new short [1];
OS.GetEventParameter (theEvent, OS.kEventParamControlPart, OS.typeControlPartCode, null, 2, null, part);
if (part [0] != OS.kControlFocusNoPart) {
if (caret != null) caret.setFocus ();
OS.ActivateTSMDocument (shell.imHandle);
} else {
if (caret != null) caret.killFocus ();
OS.DeactivateTSMDocument (shell.imHandle);
}
}
}
return result;
}
int kEventTextInputOffsetToPos (int nextHandler, int theEvent, int userData) {
if (ime != null) {
int result = ime.kEventTextInputOffsetToPos (nextHandler, theEvent, userData);
if (result != OS.eventNotHandledErr) return result;
}
return super.kEventTextInputOffsetToPos (nextHandler, theEvent, userData);
}
int kEventTextInputPosToOffset (int nextHandler, int theEvent, int userData) {
if (ime != null) {
int result = ime.kEventTextInputPosToOffset (nextHandler, theEvent, userData);
if (result != OS.eventNotHandledErr) return result;
}
return super.kEventTextInputPosToOffset (nextHandler, theEvent, userData);
}
int kEventTextInputUnicodeForKeyEvent (int nextHandler, int theEvent, int userData) {
int result = super.kEventTextInputUnicodeForKeyEvent(nextHandler, theEvent, userData);
if (result != OS.noErr) {
if (caret != null) {
if (OS.CGCursorIsVisible ()) OS.CGDisplayHideCursor (OS.CGMainDisplayID ());
}
}
return result;
}
int kEventTextInputUpdateActiveInputArea (int nextHandler, int theEvent, int userData) {
if (ime != null) {
int result = ime.kEventTextInputUpdateActiveInputArea (nextHandler, theEvent, userData);
if (result != OS.eventNotHandledErr) return result;
}
return super.kEventTextInputUpdateActiveInputArea (nextHandler, theEvent, userData);
}
int kEventTextInputGetSelectedText (int nextHandler, int theEvent, int userData) {
if (ime != null) {
int result = ime.kEventTextInputGetSelectedText (nextHandler, theEvent, userData);
if (result != OS.eventNotHandledErr) return result;
}
return super.kEventTextInputGetSelectedText (nextHandler, theEvent, userData);
}
void redrawWidget (int control, boolean children) {
boolean isFocus = OS.VERSION < 0x1040 && caret != null && caret.isFocusCaret ();
if (isFocus) caret.killFocus ();
super.redrawWidget (control, children);
if (isFocus) caret.setFocus ();
}
void redrawWidget (int control, int x, int y, int width, int height, boolean all) {
boolean isFocus = OS.VERSION < 0x1040 && caret != null && caret.isFocusCaret ();
if (isFocus) caret.killFocus ();
super.redrawWidget (control, x, y, width, height, all);
if (isFocus) caret.setFocus ();
}
void releaseChildren (boolean destroy) {
if (caret != null) {
caret.release (false);
caret = null;
}
if (ime != null) {
ime.release (false);
ime = null;
}
super.releaseChildren (destroy);
}
void reskinChildren (int flags) {
if (caret != null) caret.reskin (flags);
if (ime != null) ime.reskin (flags);
super.reskinChildren (flags);
}
/**
* Scrolls a rectangular area of the receiver by first copying
* the source area to the destination and then causing the area
* of the source which is not covered by the destination to
* be repainted. Children that intersect the rectangle are
* optionally moved during the operation. In addition, all outstanding
* paint events are flushed before the source area is copied to
* ensure that the contents of the canvas are drawn correctly.
*
* @param destX the x coordinate of the destination
* @param destY the y coordinate of the destination
* @param x the x coordinate of the source
* @param y the y coordinate of the source
* @param width the width of the area
* @param height the height of the area
* @param all <code>true</code>if children should be scrolled, and <code>false</code> otherwise
*
* @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 scroll (int destX, int destY, int x, int y, int width, int height, boolean all) {
checkWidget();
if (width <= 0 || height <= 0) return;
int deltaX = destX - x, deltaY = destY - y;
if (deltaX == 0 && deltaY == 0) return;
if (!isDrawing ()) return;
if (!OS.IsControlVisible (handle)) return;
boolean isFocus = caret != null && caret.isFocusCaret ();
if (isFocus) caret.killFocus ();
Rectangle clientRect = getClientArea ();
Rectangle sourceRect = new Rectangle (x, y, width, height);
if (sourceRect.intersects (clientRect)) {
update (all);
}
Control control = findBackgroundControl ();
if (control != null && control.backgroundImage != null) {
redrawWidget (handle, x, y, width, height, false);
redrawWidget (handle, destX, destY, width, height, false);
} else {
GC gc = new GC (this);
gc.copyArea (x, y, width, height, destX, destY);
gc.dispose ();
}
if (all) {
Control [] children = _getChildren ();
for (int i=0; i<children.length; i++) {
Control child = children [i];
Rectangle rect = child.getBounds ();
if (Math.min(x + width, rect.x + rect.width) >= Math.max (x, rect.x) &&
Math.min(y + height, rect.y + rect.height) >= Math.max (y, rect.y)) {
child.setLocation (rect.x + deltaX, rect.y + deltaY);
}
}
}
if (isFocus) caret.setFocus ();
}
/**
* Sets the receiver's caret.
* <p>
* The caret for the control is automatically hidden
* and shown when the control is painted or resized,
* when focus is gained or lost and when an the control
* is scrolled. To avoid drawing on top of the caret,
* the programmer must hide and show the caret when
* drawing in the window any other time.
* </p>
* @param caret the new caret for the receiver, may be null
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_INVALID_ARGUMENT - if the caret 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>
*/
public void setCaret (Caret caret) {
checkWidget();
Caret newCaret = caret;
Caret oldCaret = this.caret;
this.caret = newCaret;
if (hasFocus ()) {
if (oldCaret != null) oldCaret.killFocus ();
if (newCaret != null) {
if (newCaret.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
newCaret.setFocus ();
}
}
}
public void setFont (Font font) {
checkWidget ();
if (caret != null) caret.setFont (font);
super.setFont (font);
}
/**
* Sets the receiver's IME.
*
* @param ime the new IME for the receiver, may be null
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_INVALID_ARGUMENT - if the IME 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 setIME (IME ime) {
checkWidget ();
if (ime != null && ime.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
this.ime = ime;
}
}