/*******************************************************************************
* Copyright (c) 2000, 2011 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.*;
/**
* This class is the abstract superclass of the classes
* that represent the built in platform dialogs.
* A <code>Dialog</code> typically contains other widgets
* that are not accessible. A <code>Dialog</code> is not
* a <code>Widget</code>.
* <p>
* This class can also be used as the abstract superclass
* for user-designed dialogs. Such dialogs usually consist
* of a Shell with child widgets. The basic template for a
* user-defined dialog typically looks something like this:
* <pre><code>
* public class MyDialog extends Dialog {
* Object result;
*
* public MyDialog (Shell parent, int style) {
* super (parent, style);
* }
* public MyDialog (Shell parent) {
* this (parent, 0); // your default style bits go here (not the Shell's style bits)
* }
* public Object open () {
* Shell parent = getParent();
* Shell shell = new Shell(parent, SWT.DIALOG_TRIM | SWT.APPLICATION_MODAL);
* shell.setText(getText());
* // Your code goes here (widget creation, set result, etc).
* shell.open();
* Display display = parent.getDisplay();
* while (!shell.isDisposed()) {
* if (!display.readAndDispatch()) display.sleep();
* }
* return result;
* }
* }
* </pre></code>
* <p>
* Note: The <em>modality</em> styles supported by this class
* are treated as <em>HINT</em>s, because not all are supported
* by every subclass on every platform. If a modality style is
* not supported, it is "upgraded" to a more restrictive modality
* style that is supported. For example, if <code>PRIMARY_MODAL</code>
* is not supported by a particular dialog, it would be upgraded to
* <code>APPLICATION_MODAL</code>. In addition, as is the case
* for shells, the window manager for the desktop on which the
* instance is visible has ultimate control over the appearance
* and behavior of the instance, including its modality.
* <dl>
* <dt><b>Styles:</b></dt>
* <dd>APPLICATION_MODAL, PRIMARY_MODAL, SYSTEM_MODAL, SHEET</dd>
* <dt><b>Events:</b></dt>
* <dd>(none)</dd>
* </dl>
* <p>
* Note: Only one of the styles APPLICATION_MODAL, PRIMARY_MODAL,
* and SYSTEM_MODAL may be specified.
* </p>
*
* @see Shell
* @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 abstract class Dialog {
int style;
Shell parent;
String title;
/**
* Constructs a new instance of this class given only its
* parent.
*
* @param parent a shell which will be the parent of the new instance
*
* @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>
*/
public Dialog (Shell parent) {
this (parent, SWT.PRIMARY_MODAL);
}
/**
* 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.
*
* @param parent a shell which will be the parent of the new instance
* @param style the style of dialog 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#PRIMARY_MODAL
* @see SWT#APPLICATION_MODAL
* @see SWT#SYSTEM_MODAL
*/
public Dialog (Shell parent, int style) {
checkParent (parent);
this.parent = parent;
this.style = style;
title = "";
}
/**
* Checks that this class can be subclassed.
* <p>
* IMPORTANT: See the comment in <code>Widget.checkSubclass()</code>.
* </p>
*
* @exception SWTException <ul>
* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
* </ul>
*
* @see Widget#checkSubclass
*/
protected void checkSubclass () {
if (!Display.isValidClass (getClass ())) {
error (SWT.ERROR_INVALID_SUBCLASS);
}
}
/**
* Throws an exception if the specified widget can not be
* used as a parent for the receiver.
*
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
* <li>ERROR_INVALID_ARGUMENT - if the parent is disposed</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
* </ul>
*/
void checkParent (Shell parent) {
if (parent == null) error (SWT.ERROR_NULL_ARGUMENT);
parent.checkWidget ();
}
static int checkStyle (Shell parent, int style) {
int mask = SWT.PRIMARY_MODAL | SWT.APPLICATION_MODAL | SWT.SYSTEM_MODAL;
if ((style & SWT.SHEET) != 0) {
style &= ~SWT.SHEET;
if ((style & mask) == 0) {
style |= parent == null ? SWT.APPLICATION_MODAL : SWT.PRIMARY_MODAL;
}
}
if ((style & mask) == 0) {
style |= SWT.APPLICATION_MODAL;
}
style &= ~SWT.MIRRORED;
if ((style & (SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT)) == 0) {
if (parent != null) {
if ((parent.style & SWT.LEFT_TO_RIGHT) != 0) style |= SWT.LEFT_TO_RIGHT;
if ((parent.style & SWT.RIGHT_TO_LEFT) != 0) style |= SWT.RIGHT_TO_LEFT;
}
}
return Widget.checkBits (style, SWT.LEFT_TO_RIGHT, SWT.RIGHT_TO_LEFT, 0, 0, 0, 0);
}
/**
* Does whatever dialog specific cleanup is required, and then
* uses the code in <code>SWTError.error</code> to handle the error.
*
* @param code the descriptive error code
*
* @see SWT#error(int)
*/
void error (int code) {
SWT.error(code);
}
/**
* Returns the receiver's parent, which must be a <code>Shell</code>
* or null.
*
* @return the receiver's parent
*
* @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 Shell getParent () {
return parent;
}
/**
* Returns the receiver's style information.
* <p>
* Note that, the value which is returned by this method <em>may
* not match</em> the value which was provided to the constructor
* when the receiver was created.
* </p>
*
* @return the style bits
*
* @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 int getStyle () {
return style;
}
/**
* Returns the receiver's text, which is the string that the
* window manager will typically display as the receiver's
* <em>title</em>. If the text has not previously been set,
* returns an empty string.
*
* @return the 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 () {
return title;
}
/**
* Sets the receiver's text, which is the string that the
* window manager will typically display as the receiver's
* <em>title</em>, to the argument, which must not be null.
*
* @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) {
if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
title = string;
}
}