/******************************************************************************* * 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.motif.*; import org.eclipse.swt.*; import org.eclipse.swt.graphics.*; /** * Instances of this class provide an i-beam that is typically used * as the insertion point for text. *
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Styles:
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Events:
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* IMPORTANT: This class is intended to be subclassed only * within the SWT implementation. *

* * @see Caret snippets * @see SWT Example: ControlExample, Canvas tab * @see Sample code and further information * @noextend This class is not intended to be subclassed by clients. */ public class Caret extends Widget { Canvas parent; int x, y, width, height; boolean isVisible, isShowing; int blinkRate; Image image; Font font; /** * Constructs a new instance of this class given its parent * and a style value describing its behavior and appearance. *

* The style value is either one of the style constants defined in * class SWT which is applicable to instances of this * class, or must be built by bitwise OR'ing together * (that is, using the int "|" operator) two or more * of those SWT style constants. The class description * lists the style constants that are applicable to the class. * Style bits are also inherited from superclasses. *

* * @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 * @exception SWTException * * @see SWT * @see Widget#checkSubclass * @see Widget#getStyle */ public Caret (Canvas parent, int style) { super (parent, style); this.parent = parent; createWidget (0); } boolean blinkCaret () { if (!isVisible) return true; if (!isShowing) return showCaret (); if (blinkRate == 0) return true; return hideCaret (); } void createWidget (int index) { super.createWidget (index); blinkRate = display.getCaretBlinkTime (); isVisible = true; if (parent.getCaret () == null) { parent.setCaret (this); } } boolean drawCaret () { if (parent == null) return false; if (parent.isDisposed ()) return false; int handle = parent.handle; int window = OS.XtWindow (handle); if (window == 0) return false; int xDisplay = OS.XtDisplay (handle); int gc = OS.XCreateGC (xDisplay, window, 0, null); int color; if (OS.IsSunOS) { int foreground = parent.getForegroundPixel (); Control control = parent.findBackgroundControl (); if (control == null) control = parent; int background = control.getBackgroundPixel (); color = foreground ^ background; } else { int screenNum = OS.XDefaultScreen (xDisplay); color = OS.XWhitePixel(xDisplay, screenNum); } OS.XSetForeground (xDisplay, gc, color); OS.XSetFunction (xDisplay, gc, OS.GXxor); if (image != null && !image.isDisposed() && image.mask == 0) { int [] unused = new int [1]; int [] width = new int [1]; int [] height = new int [1]; OS.XGetGeometry (xDisplay, image.pixmap, unused, unused, unused, width, height, unused, unused); OS.XCopyArea(xDisplay, image.pixmap, window, gc, 0, 0, width[0], height[0], x, y); } else { int nWidth = width, nHeight = height; if (nWidth <= 0) nWidth = 1; OS.XFillRectangle (xDisplay, window, gc, x, y, nWidth, nHeight); } OS.XFreeGC (xDisplay, gc); return true; } /** * Returns a rectangle describing the receiver's size and location * relative to its parent (or its display if its parent is null). * * @return the receiver's bounding rectangle * * @exception SWTException */ public Rectangle getBounds () { checkWidget(); if (image != null) { Rectangle rect = image.getBounds (); return new Rectangle (x, y, rect.width, rect.height); } return new Rectangle (x, y, width, height); } /** * Returns the font that the receiver will use to paint textual information. * * @return the receiver's font * * @exception SWTException */ public Font getFont () { checkWidget(); if (font != null) return font; return parent.getFont (); } /** * Returns the image that the receiver will use to paint the caret. * * @return the receiver's image * * @exception SWTException */ public Image getImage () { checkWidget(); return image; } /** * Returns a point describing the receiver's location relative * to its parent (or its display if its parent is null). * * @return the receiver's location * * @exception SWTException */ public Point getLocation () { checkWidget(); return new Point (x, y); } /** * Returns the receiver's parent, which must be a Canvas. * * @return the receiver's parent * * @exception SWTException */ public Canvas getParent () { checkWidget(); return parent; } /** * Returns a point describing the receiver's size. * * @return the receiver's size * * @exception SWTException */ public Point getSize () { checkWidget(); if (image != null) { Rectangle rect = image.getBounds (); return new Point (rect.width, rect.height); } return new Point (width, height); } /** * Returns true if the receiver is visible, and * false otherwise. *

* If one of the receiver's ancestors is not visible or some * other condition makes the receiver not visible, this method * may still indicate that it is considered visible even though * it may not actually be showing. *

* * @return the receiver's visibility state * * @exception SWTException */ public boolean getVisible () { checkWidget(); return isVisible; } boolean hideCaret () { if (!isShowing) return true; isShowing = false; return drawCaret (); } /** * Returns true if the receiver is visible and all * of the receiver's ancestors are visible and false * otherwise. * * @return the receiver's visibility state * * @exception SWTException * * @see #getVisible */ public boolean isVisible () { checkWidget(); return isVisible && parent.isVisible () && parent.hasFocus (); } boolean isFocusCaret () { return this == display.currentCaret; } void killFocus () { if (display.currentCaret != this) return; display.setCurrentCaret (null); if (isVisible) hideCaret (); } void releaseParent () { super.releaseParent (); if (this == parent.getCaret ()) parent.setCaret (null); } void releaseWidget () { super.releaseWidget (); if (display.currentCaret == this) { hideCaret (); display.setCurrentCaret (null); } parent = null; image = null; } /** * Sets the receiver's size and location to the rectangular * area specified by the arguments. The x and * y arguments are relative to the receiver's * parent (or its display if its parent is null). * * @param x the new x coordinate for the receiver * @param y the new y coordinate for the receiver * @param width the new width for the receiver * @param height the new height for the receiver * * @exception SWTException */ public void setBounds (int x, int y, int width, int height) { checkWidget(); if (this.x == x && this.y == y && this.width == width && this.height == height) return; boolean isFocus = isFocusCaret (); if (isFocus && isVisible) hideCaret (); this.x = x; this.y = y; this.width = width; this.height = height; if (isVisible) parent.updateIM (); if (isFocus && isVisible) showCaret (); } /** * Sets the receiver's size and location to the rectangular * area specified by the argument. The x and * y fields of the rectangle are relative to * the receiver's parent (or its display if its parent is null). * * @param rect the new bounds for the receiver * * @exception SWTException */ public void setBounds (Rectangle rect) { checkWidget(); if (rect == null) error (SWT.ERROR_NULL_ARGUMENT); setBounds (rect.x, rect.y, rect.width, rect.height); } void setFocus () { if (display.currentCaret == this) return; display.setCurrentCaret (this); if (isVisible) showCaret (); } /** * Sets the font that the receiver will use to paint textual information * to the font specified by the argument, or to the default font for that * kind of control if the argument is null. * * @param font the new font (or null) * * @exception IllegalArgumentException * @exception SWTException */ public void setFont (Font font) { checkWidget(); if (font != null && font.isDisposed ()) { error (SWT.ERROR_INVALID_ARGUMENT); } this.font = font; if (isVisible) parent.updateIM (); } /** * Sets the image that the receiver will use to paint the caret * to the image specified by the argument, or to the default * which is a filled rectangle if the argument is null * * @param image the new image (or null) * * @exception IllegalArgumentException * @exception SWTException */ public void setImage (Image image) { checkWidget(); if (image != null && image.isDisposed ()) { error (SWT.ERROR_INVALID_ARGUMENT); } boolean isFocus = isFocusCaret (); if (isFocus && isVisible) hideCaret (); this.image = image; if (isFocus && isVisible) showCaret (); } /** * Sets the receiver's location to the point specified by * the arguments which are relative to the receiver's * parent (or its display if its parent is null). * * @param x the new x coordinate for the receiver * @param y the new y coordinate for the receiver * * @exception SWTException */ public void setLocation (int x, int y) { checkWidget(); setBounds (x, y, width, height); } /** * Sets the receiver's location to the point specified by * the argument which is relative to the receiver's * parent (or its display if its parent is null). * * @param location the new location for the receiver * * @exception SWTException */ public void setLocation (Point location) { checkWidget(); if (location == null) error (SWT.ERROR_NULL_ARGUMENT); setLocation (location.x, location.y); } /** * Sets the receiver's size to the point specified by the arguments. * * @param width the new width for the receiver * @param height the new height for the receiver * * @exception SWTException */ public void setSize (int width, int height) { checkWidget(); setBounds (x, y, width, height); } /** * Sets the receiver's size to the point specified by the argument. * * @param size the new extent for the receiver * * @exception IllegalArgumentException * @exception SWTException */ public void setSize (Point size) { checkWidget(); if (size == null) error (SWT.ERROR_NULL_ARGUMENT); setSize (size.x, size.y); } /** * Marks the receiver as visible if the argument is true, * and marks it invisible otherwise. *

* If one of the receiver's ancestors is not visible or some * other condition makes the receiver not visible, marking * it visible may not actually cause it to be displayed. *

* * @param visible the new visibility state * * @exception SWTException */ public void setVisible (boolean visible) { checkWidget(); if (visible == isVisible) return; isVisible = visible; if (!isFocusCaret ()) return; if (isVisible) { showCaret (); } else { hideCaret (); } } boolean showCaret () { if (isShowing) return true; isShowing = true; return drawCaret (); } }