package org.eclipse.swt.widgets; | |
/* | |
* Copyright (c) 2000, 2002 IBM Corp. All rights reserved. | |
* This file is made available under the terms of the Common Public License v1.0 | |
* which accompanies this distribution, and is available at | |
* http://www.eclipse.org/legal/cpl-v10.html | |
*/ | |
import org.eclipse.swt.*; | |
import org.eclipse.swt.graphics.*; | |
/** | |
* This class is the abstract superclass of all non-windowed | |
* user interface objects that occur within specific controls. | |
* For example, a tree will contain tree items. | |
* <dl> | |
* <dt><b>Styles:</b></dt> | |
* <dd>(none)</dd> | |
* <dt><b>Events:</b></dt> | |
* <dd>(none)</dd> | |
* </dl> | |
*/ | |
public abstract class Item extends Widget { | |
String text; | |
Image image; | |
/** | |
* Constructs a new instance of this class given its parent | |
* and a style value describing its behavior and appearance. | |
* The item is added to the end of the items maintained by its parent. | |
* <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 item 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 #getStyle | |
*/ | |
public Item (Widget parent, int style) { | |
super (parent, style); | |
text = ""; | |
} | |
/** | |
* Constructs a new instance of this class given its parent | |
* and a style value describing its behavior and appearance, | |
* and the index at which to place it in the items maintained | |
* by its parent. | |
* <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 item to construct | |
* @param index the index at which to store the receiver in its parent | |
* | |
* @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 #getStyle | |
*/ | |
public Item (Widget parent, int style, int index) { | |
this (parent, style); | |
} | |
protected void checkSubclass () { | |
/* Do Nothing - Subclassing is allowed */ | |
} | |
/** | |
* Returns the receiver's image if it has one, or null | |
* if it does not. | |
* | |
* @return the receiver's image | |
* | |
* @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 Image getImage () { | |
checkWidget (); | |
return image; | |
} | |
String getNameText () { | |
return getText (); | |
} | |
/** | |
* Returns the receiver's text, which will be an empty | |
* string if it has never been set. | |
* | |
* @return the receiver's text | |
* | |
* @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 String getText () { | |
checkWidget(); | |
return text; | |
} | |
void releaseWidget () { | |
super.releaseWidget (); | |
text = null; | |
image = null; | |
} | |
/** | |
* Sets the receiver's image to the argument, which may be | |
* null indicating that no image should be displayed. | |
* | |
* @param image the image to display on the receiver (may be null) | |
* | |
* @exception IllegalArgumentException <ul> | |
* <li>ERROR_INVALID_ARGUMENT - if the image 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 setImage (Image image) { | |
checkWidget (); | |
if (image != null && image.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT); | |
this.image = image; | |
} | |
/** | |
* Sets the receiver's text. | |
* | |
* @param string the new text | |
* | |
* @exception IllegalArgumentException <ul> | |
* <li>ERROR_NULL_ARGUMENT - if the text is null</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 setText (String string) { | |
checkWidget (); | |
text = string; | |
} | |
} |