dialog.java

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	 * 
	 * @param parentShell
	 *            object that returns the current parent shell
	 * 
	 * @since 3.1
	 */
	protected Dialog(IShellProvider parentShell) {
		super(parentShell);
		setShellStyle(SWT.DIALOG_TRIM | SWT.APPLICATION_MODAL
				| getDefaultOrientation());
		setBlockOnOpen(true);
	}

	/**
	 * Notifies that this dialog's button with the given id has been pressed.
	 * <p>
	 * The <code>Dialog</code> implementation of this framework method calls
	 * <code>okPressed</code> if the ok button is the pressed, and
	 * <code>cancelPressed</code> if the cancel button is the pressed. All
	 * other button presses are ignored. Subclasses may override to handle other
	 * buttons, but should call <code>super.buttonPressed</code> if the
	 * default handling of the ok and cancel buttons is desired.
	 * </p>
	 * 
	 * @param buttonId
	 *            the id of the button that was pressed (see
	 *            <code>IDialogConstants.*_ID</code> constants)
	 */
	protected void buttonPressed(int buttonId) {
		if (IDialogConstants.OK_ID == buttonId) {
			okPressed();
		} else if (IDialogConstants.CANCEL_ID == buttonId) {
			cancelPressed();
		}
	}

	/**
	 * Notifies that the cancel button of this dialog has been pressed.
	 * <p>
	 * The <code>Dialog</code> implementation of this framework method sets
	 * this dialog's return code to <code>Window.CANCEL</code> and closes the
	 * dialog. Subclasses may override if desired.
	 * </p>
	 */
	protected void cancelPressed() {
		setReturnCode(CANCEL);
		close();
	}

	/**
	 * Returns the number of pixels corresponding to the height of the given
	 * number of characters.
	 * <p>
	 * This method may only be called after <code>initializeDialogUnits</code>
	 * has been called.
	 * </p>
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 * 
	 * @param chars
	 *            the number of characters
	 * @return the number of pixels
	 */
	protected int convertHeightInCharsToPixels(int chars) {
		// test for failure to initialize for backward compatibility
		if (fontMetrics == null) {
			return 0;
		}
		return convertHeightInCharsToPixels(fontMetrics, chars);
	}

	/**
	 * Returns the number of pixels corresponding to the given number of
	 * horizontal dialog units.
	 * <p>
	 * This method may only be called after <code>initializeDialogUnits</code>
	 * has been called.
	 * </p>
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 * 
	 * @param dlus
	 *            the number of horizontal dialog units
	 * @return the number of pixels
	 */
	protected int convertHorizontalDLUsToPixels(int dlus) {
		// test for failure to initialize for backward compatibility
		if (fontMetrics == null) {
			return 0;
		}
		return convertHorizontalDLUsToPixels(fontMetrics, dlus);
	}

	/**
	 * Returns the number of pixels corresponding to the given number of
	 * vertical dialog units.
	 * <p>
	 * This method may only be called after <code>initializeDialogUnits</code>
	 * has been called.
	 * </p>
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 * 
	 * @param dlus
	 *            the number of vertical dialog units
	 * @return the number of pixels
	 */
	protected int convertVerticalDLUsToPixels(int dlus) {
		// test for failure to initialize for backward compatibility
		if (fontMetrics == null) {
			return 0;
		}
		return convertVerticalDLUsToPixels(fontMetrics, dlus);
	}

	/**
	 * Returns the number of pixels corresponding to the width of the given
	 * number of characters.
	 * <p>
	 * This method may only be called after <code>initializeDialogUnits</code>
	 * has been called.
	 * </p>
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 * 
	 * @param chars
	 *            the number of characters
	 * @return the number of pixels
	 */
	protected int convertWidthInCharsToPixels(int chars) {
		// test for failure to initialize for backward compatibility
		if (fontMetrics == null) {
			return 0;
		}
		return convertWidthInCharsToPixels(fontMetrics, chars);
	}

	/**
	 * Creates a new button with the given id.
	 * <p>
	 * The <code>Dialog</code> implementation of this framework method creates
	 * a standard push button, registers it for selection events including
	 * button presses, and registers default buttons with its shell. The button
	 * id is stored as the button's client data. If the button id is
	 * <code>IDialogConstants.CANCEL_ID</code>, the new button will be
	 * accessible from <code>getCancelButton()</code>. If the button id is
	 * <code>IDialogConstants.OK_ID</code>, the new button will be accesible
	 * from <code>getOKButton()</code>. Note that the parent's layout is
	 * assumed to be a <code>GridLayout</code> and the number of columns in
	 * this layout is incremented. Subclasses may override.
	 * </p>
	 * 
	 * @param parent
	 *            the parent composite
	 * @param id
	 *            the id of the button (see <code>IDialogConstants.*_ID</code>
	 *            constants for standard dialog button ids)
	 * @param label
	 *            the label from the button
	 * @param defaultButton
	 *            <code>true</code> if the button is to be the default button,
	 *            and <code>false</code> otherwise
	 * 
	 * @return the new button
	 * 
	 * @see #getCancelButton
	 * @see #getOKButton()
	 */
	protected Button createButton(Composite parent, int id, String label,
			boolean defaultButton) {
		// increment the number of columns in the button bar
		((GridLayout) parent.getLayout()).numColumns++;
		Button button = new Button(parent, SWT.PUSH);
		button.setText(label);
		button.setFont(JFaceResources.getDialogFont());
		button.setData(new Integer(id));
		button.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent event) {
				buttonPressed(((Integer) event.widget.getData()).intValue());
			}
		});
		if (defaultButton) {
			Shell shell = parent.getShell();
			if (shell != null) {
				shell.setDefaultButton(button);
			}
		}
		buttons.put(new Integer(id), button);
		setButtonLayoutData(button);
		return button;
	}

	/**
	 * Creates and returns the contents of this dialog's button bar.
	 * <p>
	 * The <code>Dialog</code> implementation of this framework method lays
	 * out a button bar and calls the <code>createButtonsForButtonBar</code>
	 * framework method to populate it. Subclasses may override.
	 * </p>
	 * <p>
	 * The returned control's layout data must be an instance of
	 * <code>GridData</code>.
	 * </p>
	 * 
	 * @param parent
	 *            the parent composite to contain the button bar
	 * @return the button bar control
	 */
	protected Control createButtonBar(Composite parent) {
		Composite composite = new Composite(parent, SWT.NONE);
		// create a layout with spacing and margins appropriate for the font
		// size.
		GridLayout layout = new GridLayout();
		layout.numColumns = 0; // this is incremented by createButton
		layout.makeColumnsEqualWidth = true;
		layout.marginWidth = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_MARGIN);
		layout.marginHeight = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_MARGIN);
		layout.horizontalSpacing = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING);
		layout.verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);
		composite.setLayout(layout);
		GridData data = new GridData(GridData.HORIZONTAL_ALIGN_END
				| GridData.VERTICAL_ALIGN_CENTER);
		composite.setLayoutData(data);
		composite.setFont(parent.getFont());
		
		// Add the buttons to the button bar.
		createButtonsForButtonBar(composite);
		return composite;
	}

	/**
	 * Adds buttons to this dialog's button bar.
	 * <p>
	 * The <code>Dialog</code> implementation of this framework method adds
	 * standard ok and cancel buttons using the <code>createButton</code>
	 * framework method. These standard buttons will be accessible from
	 * <code>getCancelButton</code>, and <code>getOKButton</code>.
	 * Subclasses may override.
	 * </p>
	 * 
	 * @param parent
	 *            the button bar composite
	 */
	protected void createButtonsForButtonBar(Composite parent) {
		// create OK and Cancel buttons by default
		createButton(parent, IDialogConstants.OK_ID, IDialogConstants.OK_LABEL,
				true);
		createButton(parent, IDialogConstants.CANCEL_ID,
				IDialogConstants.CANCEL_LABEL, false);
	}

	/*
	 * @see Window.initializeBounds()
	 */
	protected void initializeBounds() {
		String platform = SWT.getPlatform();
		if ("carbon".equals(platform)) { //$NON-NLS-1$
			// On Mac OS X the default button must be the right-most button
			Shell shell = getShell();
			if (shell != null) {
				Button defaultButton = shell.getDefaultButton();
				if (defaultButton != null
						&& isContained(buttonBar, defaultButton)) {
					defaultButton.moveBelow(null);
				}
			}
		}
		
		// Store the computed size for the dialog.  Must be done here before
		// any dialog settings are applied.  We don't do this in the create methods
		// because the dialog font is applied after creation and before the bounds
		// are initialized.
		computedSize = getShell().computeSize(SWT.DEFAULT, SWT.DEFAULT, true);	
		
		super.initializeBounds();
	}

	/**
	 * Returns true if the given Control is a direct or indirect child of
	 * container.
	 * 
	 * @param container
	 *            the potential parent
	 * @param control
	 * @return boolean <code>true</code> if control is a child of container
	 */
	private boolean isContained(Control container, Control control) {
		Composite parent;
		while ((parent = control.getParent()) != null) {
			if (parent == container) {
				return true;
			}
			control = parent;
		}
		return false;
	}

	/**
	 * The <code>Dialog</code> implementation of this <code>Window</code>
	 * method creates and lays out the top level composite for the dialog, and
	 * determines the appropriate horizontal and vertical dialog units based on
	 * the font size. It then calls the <code>createDialogArea</code> and
	 * <code>createButtonBar</code> methods to create the dialog area and
	 * button bar, respectively. Overriding <code>createDialogArea</code> and
	 * <code>createButtonBar</code> are recommended rather than overriding
	 * this method.
	 */
	protected Control createContents(Composite parent) {
		// create the top level composite for the dialog
		Composite composite = new Composite(parent, 0);
		GridLayout layout = new GridLayout();
		layout.marginHeight = 0;
		layout.marginWidth = 0;
		layout.verticalSpacing = 0;
		composite.setLayout(layout);
		composite.setLayoutData(new GridData(GridData.FILL_BOTH));
		applyDialogFont(composite);
		// initialize the dialog units
		initializeDialogUnits(composite);
		// create the dialog area and button bar
		dialogArea = createDialogArea(composite);
		buttonBar = createButtonBar(composite);
				
		return composite;
	}

	/**
	 * Creates and returns the contents of the upper part of this dialog (above
	 * the button bar).
	 * <p>
	 * The <code>Dialog</code> implementation of this framework method creates
	 * and returns a new <code>Composite</code> with standard margins and
	 * spacing.
	 * </p>
	 * <p>
	 * The returned control's layout data must be an instance of
	 * <code>GridData</code>. This method must not modify the parent's
	 * layout.
	 * </p>
	 * <p>
	 * Subclasses must override this method but may call <code>super</code> as
	 * in the following example:
	 * </p>
	 * 
	 * <pre>
	 * Composite composite = (Composite) super.createDialogArea(parent);
	 * //add controls to composite as necessary
	 * return composite;
	 * </pre>
	 * 
	 * @param parent
	 *            the parent composite to contain the dialog area
	 * @return the dialog area control
	 */
	protected Control createDialogArea(Composite parent) {
		// create a composite with standard margins and spacing
		Composite composite = new Composite(parent, SWT.NONE);
		GridLayout layout = new GridLayout();
		layout.marginHeight = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_MARGIN);
		layout.marginWidth = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_MARGIN);
		layout.verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);
		layout.horizontalSpacing = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING);
		composite.setLayout(layout);
		composite.setLayoutData(new GridData(GridData.FILL_BOTH));
		applyDialogFont(composite);
		return composite;
	}

	/**
	 * Returns the button created by the method <code>createButton</code> for
	 * the specified ID as defined on <code>IDialogConstants</code>. If
	 * <code>createButton</code> was never called with this ID, or if
	 * <code>createButton</code> is overridden, this method will return
	 * <code>null</code>.
	 * 
	 * @param id
	 *            the id of the button to look for
	 * 
	 * @return the button for the ID or <code>null</code>
	 * 
	 * @see #createButton(Composite, int, String, boolean)
	 * @since 2.0
	 */
	protected Button getButton(int id) {
		return (Button) buttons.get(new Integer(id));
	}

	/**
	 * Returns the button bar control.
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 * 
	 * @return the button bar, or <code>null</code> if the button bar has not
	 *         been created yet
	 */
	protected Control getButtonBar() {
		return buttonBar;
	}

	/**
	 * Returns the button created when <code>createButton</code> is called
	 * with an ID of <code>IDialogConstants.CANCEL_ID</code>. If
	 * <code>createButton</code> was never called with this parameter, or if
	 * <code>createButton</code> is overridden, <code>getCancelButton</code>
	 * will return <code>null</code>.
	 * 
	 * @return the cancel button or <code>null</code>
	 * 
	 * @see #createButton(Composite, int, String, boolean)
	 * @since 2.0
	 * @deprecated Use <code>getButton(IDialogConstants.CANCEL_ID)</code>
	 *             instead. This method will be removed soon.
	 */
	protected Button getCancelButton() {
		return getButton(IDialogConstants.CANCEL_ID);
	}

	/**
	 * Returns the dialog area control.
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 * 
	 * @return the dialog area, or <code>null</code> if the dialog area has
	 *         not been created yet
	 */
	protected Control getDialogArea() {
		return dialogArea;
	}

	/**
	 * Returns the standard dialog image with the given key. Note that these
	 * images are managed by the dialog framework, and must not be disposed by
	 * another party.
	 * 
	 * @param key
	 *            one of the <code>Dialog.DLG_IMG_* </code> constants
	 * @return the standard dialog image
	 */
	public static Image getImage(String key) {
		return JFaceResources.getImageRegistry().get(key);
	}

	/**
	 * Returns the button created when <code>createButton</code> is called
	 * with an ID of <code>IDialogConstants.OK_ID</code>. If
	 * <code>createButton</code> was never called with this parameter, or if
	 * <code>createButton</code> is overridden, <code>getOKButton</code>
	 * will return <code>null</code>.
	 * 
	 * @return the OK button or <code>null</code>
	 * 
	 * @see #createButton(Composite, int, String, boolean)
	 * @since 2.0
	 * @deprecated Use <code>getButton(IDialogConstants.OK_ID)</code> instead.
	 *             This method will be removed soon.
	 */
	protected Button getOKButton() {
		return getButton(IDialogConstants.OK_ID);
	}

	/**
	 * Initializes the computation of horizontal and vertical dialog units based
	 * on the size of current font.
	 * <p>
	 * This method must be called before any of the dialog unit based conversion
	 * methods are called.
	 * </p>
	 * 
	 * @param control
	 *            a control from which to obtain the current font
	 */