bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/dialogs/FontPreferencePage.java - platform/eclipse.platform.ui - Git at Google

 package org.eclipse.ui.internal.dialogs;

 /*
  * Copyright (c) 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 java.text.Collator;
 import java.util.ArrayList;
 import java.util.Hashtable;
 import java.util.Iterator;
 import java.util.Set;

 import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.jface.preference.PreferenceConverter;
 import org.eclipse.jface.preference.PreferencePage;
 import org.eclipse.jface.resource.JFaceResources;
 import org.eclipse.jface.resource.StringConverter;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.DisposeEvent;
 import org.eclipse.swt.events.DisposeListener;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Font;
 import org.eclipse.swt.graphics.FontData;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.FontDialog;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.swt.widgets.Text;
 import org.eclipse.swt.widgets.List;
 import org.eclipse.ui.IWorkbench;
 import org.eclipse.ui.IWorkbenchPreferencePage;
 import org.eclipse.ui.help.WorkbenchHelp;
 import org.eclipse.ui.internal.IHelpContextIds;
 import org.eclipse.ui.internal.WorkbenchMessages;
 import org.eclipse.ui.internal.WorkbenchPlugin;
 import org.eclipse.ui.internal.fonts.FontDefinition;
 import org.eclipse.ui.internal.misc.Sorter;

 public class FontPreferencePage
 	extends PreferencePage
 	implements IWorkbenchPreferencePage {

 	private Hashtable labelsToDefinitions;
 	private Hashtable fontDataSettings;
 	private List fontList;
 	private Button changeFontButton;
 	private Button useSystemButton;
 	private Text descriptionText;
 	private Font appliedDialogFont;

 	private ArrayList dialogFontWidgets = new ArrayList();

 	//A token to identify a reset font
 	private String DEFAULT_TOKEN = "DEFAULT";

 	/**
 	 * The label that displays the selected font, or <code>null</code> if none.
 	 */
 	private Label valueControl;

 	/**
 	 * The previewer, or <code>null</code> if none.
 	 */
 	private DefaultPreviewer previewer;

 	private static class DefaultPreviewer {
 		private Text text;
 		private Font font;
 		public DefaultPreviewer(Composite parent) {
 			text = new Text(parent, SWT.READ_ONLY | SWT.BORDER | SWT.WRAP);
 			text.addDisposeListener(new DisposeListener() {
 				public void widgetDisposed(DisposeEvent e) {
 					if (font != null)
 						font.dispose();
 				}
 			});
 		}

 		public Control getControl() {
 			return text;
 		}

 		public void setFont(FontData[] fontData) {
 			if (font != null)
 				font.dispose();

 			FontData[] bestData =
 				JFaceResources.getFontRegistry().bestDataArray(
 					fontData,
 					text.getDisplay());

 			//If there are no specified values then return.
 			if (bestData == null)
 				return;

 			font = new Font(text.getDisplay(), bestData);
 			text.setFont(font);
 			//Also set the text here
 			text.setText(WorkbenchMessages.getString("FontsPreference.SampleText")); //$NON-NLS-1$
 		}
 		public int getPreferredHeight() {
 			return 120;
 		}
 	}

 	/**
 	 * Apply the dialog font to the control and store
 	 * it for later so that it can be used for a later
 	 * update.
 	 * @param control
 	 */
 	private void applyDialogFont(Control control) {
 		control.setFont(JFaceResources.getDialogFont());
 		dialogFontWidgets.add(control);
 	}

 	/**
 	 * Update for a change in the dialog font.
 	 * @param newFont
 	 */
 	private void updateForDialogFontChange(Font newFont) {
 		Iterator iterator = dialogFontWidgets.iterator();
 		while (iterator.hasNext()) {
 			((Control) iterator.next()).setFont(newFont);
 		}
 	}

 	/*
 	 * @see PreferencePage#createContents
 	 */
 	public Control createContents(Composite parent) {
 		WorkbenchHelp.setHelp(
 			getControl(),
 			IHelpContextIds.FONT_PREFERENCE_PAGE);

 		parent.addDisposeListener(new DisposeListener() {
 			public void widgetDisposed(DisposeEvent e) {
 				if (appliedDialogFont != null)
 					appliedDialogFont.dispose();
 			}
 		});

 		Font defaultFont = parent.getFont();

 		Composite mainColumn = new Composite(parent, SWT.NULL);
 		GridLayout layout = new GridLayout();
 		layout.numColumns = 2;
 		layout.marginWidth = 0;
 		layout.marginHeight = 0;
 		layout.makeColumnsEqualWidth = true;
 		mainColumn.setFont(defaultFont);
 		mainColumn.setLayout(layout);

 		createFontList(mainColumn);

 		Composite previewColumn = new Composite(mainColumn, SWT.NULL);
 		layout = new GridLayout();
 		layout.numColumns = 1;
 		layout.marginHeight = 0;
 		layout.marginWidth = 0;
 		previewColumn.setLayout(layout);
 		GridData data = new GridData(GridData.FILL_BOTH);
 		data.grabExcessHorizontalSpace = true;
 		previewColumn.setLayoutData(data);
 		previewColumn.setFont(defaultFont);

 		createPreviewControl(previewColumn);
 		createValueControl(previewColumn);

 		Composite buttonColumn = new Composite(previewColumn, SWT.NULL);
 		layout = new GridLayout();
 		layout.numColumns = 2;
 		layout.marginHeight = 0;
 		layout.marginWidth = 0;
 		buttonColumn.setLayout(layout);
 		data = new GridData(GridData.HORIZONTAL_ALIGN_END);
 		buttonColumn.setLayoutData(data);
 		buttonColumn.setFont(defaultFont);

 		createUseDefaultsControl(buttonColumn, WorkbenchMessages.getString("FontsPreference.useSystemFont")); //$NON-NLS-1$
 		createChangeControl(buttonColumn, JFaceResources.getString("openChange")); //$NON-NLS-1$

 		createDescriptionControl(parent);

 		return mainColumn;
 	}

 	/**
 	 * Create the preference page.
 	 */
 	public FontPreferencePage() {
 		setPreferenceStore(WorkbenchPlugin.getDefault().getPreferenceStore());
 	}

 	/**
 	 * Create the list of possible fonts.
 	 */
 	private void createFontList(Composite firstColumn) {

 		Composite parent = new Composite(firstColumn, SWT.NULL);
 		GridLayout layout = new GridLayout();
 		layout.marginWidth = 0;
 		layout.marginHeight = 0;
 		parent.setLayout(layout);
 		GridData data = new GridData(GridData.FILL_BOTH);
 		data.grabExcessHorizontalSpace = true;
 		parent.setLayoutData(data);

 		Label label = new Label(parent, SWT.LEFT);
 		label.setText(WorkbenchMessages.getString("FontsPreference.fonts")); //$NON-NLS-1$
 		applyDialogFont(label);

 		fontList = new List(parent, SWT.BORDER);
 		data =
 			new GridData(
 				GridData.VERTICAL_ALIGN_BEGINNING | GridData.FILL_BOTH);
 		data.grabExcessHorizontalSpace = true;
 		fontList.setLayoutData(data);
 		applyDialogFont(fontList);

 		fontList.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent event) {
 				FontDefinition selectedFontDefinition =
 					getSelectedFontDefinition();
 				if (selectedFontDefinition == null) {
 					changeFontButton.setEnabled(false);
 					useSystemButton.setEnabled(false);
 				} else {
 					changeFontButton.setEnabled(true);
 					useSystemButton.setEnabled(true);
 					updateForSelectedFontDefinition(selectedFontDefinition);
 				}
 			}
 		});

 		Set names = labelsToDefinitions.keySet();
 		int nameSize = names.size();
 		String[] unsortedItems = new String[nameSize];
 		names.toArray(unsortedItems);

 		Sorter sorter = new Sorter() {
 			private Collator collator = Collator.getInstance();

 			public boolean compare(Object o1, Object o2) {
 				String s1 = (String) o1;
 				String s2 = (String) o2;
 				return collator.compare(s1, s2) < 0;
 			}
 		};

 		Object[] sortedItems = sorter.sort(unsortedItems);
 		String[] listItems = new String[nameSize];
 		System.arraycopy(sortedItems, 0, listItems, 0, nameSize);

 		fontList.setItems(listItems);
 	}

 	/**
 	 * Return the id of the currently selected font. Return
 	 * null if multiple or none are selected.
 	 */

 	private FontDefinition getSelectedFontDefinition() {
 		String[] selection = fontList.getSelection();
 		if (selection.length == 1)
 			return (FontDefinition) labelsToDefinitions.get(selection[0]);
 		else
 			return null;
 	}

 	/**
 	 * Creates the change button for this field editor.=
 	 */
 	private void createChangeControl(
 		Composite parent,
 		String changeButtonLabel) {
 		changeFontButton = new Button(parent, SWT.PUSH);

 		changeFontButton.setText(changeButtonLabel); //$NON-NLS-1$
 		applyDialogFont(changeFontButton);
 		setButtonLayoutData(changeFontButton);

 		changeFontButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent event) {
 				FontDefinition definition = getSelectedFontDefinition();
 				if (definition != null) {
 					FontDialog fontDialog =
 						new FontDialog(changeFontButton.getShell());
 					FontData[] currentData = getFontDataSetting(definition);
 					fontDialog.setFontData(currentData[0]);
 					FontData font = fontDialog.open();
 					if (font != null) {
 						FontData[] fonts = new FontData[1];
 						fonts[0] = font;
 						fontDataSettings.put(definition.getId(), fonts);
 						updateForSelectedFontDefinition(definition);
 					}

 				}

 			}
 		});

 		changeFontButton.setEnabled(false);
 	}

 	/**
 	 * Creates the Use System Font button for the editor.
 	 */
 	private void createUseDefaultsControl(
 		Composite parent,
 		String useSystemLabel) {

 		useSystemButton = new Button(parent, SWT.PUSH | SWT.CENTER);
 		useSystemButton.setText(useSystemLabel); //$NON-NLS-1$
 		applyDialogFont(useSystemButton);
 		setButtonLayoutData(useSystemButton);

 		useSystemButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent event) {
 				FontDefinition definition = getSelectedFontDefinition();
 				if (definition != null) {
 					FontData[] defaultFontData =
 						JFaceResources.getDefaultFont().getFontData();
 					fontDataSettings.put(definition.getId(), defaultFontData);
 					updateForSelectedFontDefinition(definition);
 				}
 			}
 		});

 		useSystemButton.setEnabled(false);
 	}

 	/**
 	 * Creates the preview control for this field editor.
 	 */
 	private void createPreviewControl(Composite parent) {
 		Label label = new Label(parent, SWT.LEFT);
 		label.setText(WorkbenchMessages.getString("FontsPreference.preview")); //$NON-NLS-1$
 		applyDialogFont(label);

 		previewer = new DefaultPreviewer(parent);
 		Control control = previewer.getControl();
 		GridData gd = new GridData();
 		gd.horizontalAlignment = GridData.FILL;
 		gd.grabExcessHorizontalSpace = true;
 		gd.heightHint = previewer.getPreferredHeight();
 		control.setLayoutData(gd);
 	}

 	/**
 		 * Creates the widgets for the description.
 		 */
 	private void createDescriptionControl(Composite mainComposite) {

 		Composite textComposite = new Composite(mainComposite, SWT.NONE);
 		textComposite.setLayoutData(new GridData(GridData.FILL_BOTH));
 		GridLayout textLayout = new GridLayout();
 		textLayout.marginWidth = 0;
 		textLayout.marginHeight = 0;
 		textComposite.setLayout(textLayout);

 		Label descriptionLabel = new Label(textComposite, SWT.NONE);
 		descriptionLabel.setText(WorkbenchMessages.getString("FontsPreference.description")); //$NON-NLS-1$
 		applyDialogFont(descriptionLabel);

 		descriptionText =
 			new Text(
 				textComposite,
 				SWT.MULTI
 					| SWT.WRAP
 					| SWT.READ_ONLY
 					| SWT.BORDER
 					| SWT.H_SCROLL);
 		descriptionText.setLayoutData(new GridData(GridData.FILL_BOTH));
 		applyDialogFont(descriptionText);
 	}

 	/**
 	 * Creates the value control for this field editor. The value control
 	 * displays the currently selected font name.
 	 */
 	private void createValueControl(Composite parent) {
 		valueControl = new Label(parent, SWT.CENTER);

 		valueControl.addDisposeListener(new DisposeListener() {
 			public void widgetDisposed(DisposeEvent event) {
 				valueControl = null;
 			}
 		});

 		applyDialogFont(valueControl);

 		GridData gd =
 			new GridData(
 				GridData.FILL_HORIZONTAL | GridData.HORIZONTAL_ALIGN_CENTER);

 		gd.grabExcessHorizontalSpace = true;
 		valueControl.setLayoutData(gd);
 	}

 	/**
 	 * Updates the value label and the previewer to reflect the
 	 * newly selected font definition.
 	 * @param FontDefinition
 	 */
 	private void updateForSelectedFontDefinition(FontDefinition definition) {

 		FontData[] font = getFontDataSetting(definition);

 		valueControl.setText(StringConverter.asString(font[0]));
 		previewer.setFont(font);

 		String text = definition.getDescription();
 		if (text == null || text.length() == 0)
 			descriptionText.setText(WorkbenchMessages.getString("PreferencePage.noDescription")); //$NON-NLS-1$
 		else
 			descriptionText.setText(text);
 	}

 	/**
 	 * Get the current font data setting for the definition.
 	 * @param definition
 	 * @return FontData[]
 	 */
 	private FontData[] getFontDataSetting(FontDefinition definition) {
 		String fontId = definition.getId();

 		Object setting = fontDataSettings.get(fontId);
 		if (DEFAULT_TOKEN.equals(setting))
 			return getDefaultFont(definition);
 		else
 			return (FontData[]) setting;

 	}

 	/**
 	 * Return the defualt FontData for the definition.
 	 * @param definition
 	 * @return FontData[]
 	 */
 	private FontData[] getDefaultFont(FontDefinition definition) {

 		String defaultsTo = definition.getDefaultsTo();
 		if (defaultsTo == null) {
 			return PreferenceConverter.getDefaultFontDataArray(
 				getPreferenceStore(),
 				definition.getId());
 		} else {
 			FontDefinition defaultDefinition = getDefinition(defaultsTo);
 			if (defaultDefinition == null)
 				return JFaceResources.getDefaultFont().getFontData();
 			else
 				return getFontDataSetting(defaultDefinition);
 		}
 	}

 	/*
 	 * @see IWorkbenchPreferencePage#init
 	 */
 	public void init(IWorkbench workbench) {

 		//Set up the mappings we currently have

 		labelsToDefinitions = new Hashtable();
 		//Set the user selected values to an empty table
 		fontDataSettings = new Hashtable();

 		FontDefinition[] definitions = getDefinitions();

 		for (int i = 0; i < definitions.length; i++) {
 			FontDefinition definition = definitions[i];
 			labelsToDefinitions.put(definition.getLabel(), definition);
 			Object settingValue;
 			if (getPreferenceStore().isDefault(definition.getId()))
 				settingValue = DEFAULT_TOKEN;
 			else
 				settingValue =
 					JFaceResources.getFont(definition.getId()).getFontData();
 			fontDataSettings.put(definition.getId(), settingValue);
 		}

 	}

 	/*
 	 * @see IWorkbenchPreferencePage#performDefaults
 	*/
 	protected void performDefaults() {

 		FontDefinition currentSelection = getSelectedFontDefinition();
 		FontDefinition[] definitions = getDefinitions();

 		for (int i = 0; i < definitions.length; i++) {
 			FontDefinition definition = definitions[i];

 			//Put an entry of null in to represent the reset
 			fontDataSettings.put(definition.getId(), DEFAULT_TOKEN);

 			if (definition.equals(currentSelection)) {
 				//Now we have the defaults ask the registry which to use of these
 				//values
 				updateForSelectedFontDefinition(definition);
 			}
 		}
 		super.performDefaults();
 	}

 	/*
 	 * @see IWorkbenchPreferencePage#performDefaults
 	*/
 	public boolean performOk() {

 		FontDefinition[] definitions = getDefinitions();
 		IPreferenceStore store = getPreferenceStore();
 		for (int i = 0; i < definitions.length; i++) {
 			FontDefinition definition = definitions[i];
 			String preferenceId = definition.getId();
 			String registryKey = definition.getId();

 			Object setValue = fontDataSettings.get(preferenceId);

 			if (DEFAULT_TOKEN.equals(setValue)) {
 				store.setToDefault(registryKey);
 			} else {
 				FontData[] newData = (FontData[]) setValue;
 				//Don't update the preference store if there has been no change
 				if (!newData
 					.equals(
 						PreferenceConverter.getFontData(store, registryKey))) {
 					PreferenceConverter.setValue(store, registryKey, newData);
 				}

 			}
 		}

 		return super.performOk();
 	}

 	/**
 	 * Get the font definitions we will be using.
 	 * @return FontDefinition[]
 	 */
 	private FontDefinition[] getDefinitions() {
 		return FontDefinition.getDefinitions();
 	}

 	/**
 	 * Get the FontDefinition with the specified registryKey.
 	 * @param registryKey
 	 * @return FontDefinition
 	 */
 	private FontDefinition getDefinition(String registryKey) {
 		FontDefinition[] definitions = getDefinitions();
 		for (int i = 0; i < definitions.length; i++) {
 			if (definitions[i].getId().equals(registryKey))
 				return definitions[i];
 		}
 		return null;
 	}

 	/**
 	 * Return whether the definition has a non default setting.
 	 * @param definition
 	 * @return boolean
 	 */
 	private boolean hasSetting(FontDefinition definition) {
 		return fontDataSettings.get(definition.getId()) instanceof FontData[];
 	}

 	/**
 	 * @see org.eclipse.jface.preference.PreferencePage#performApply()
 	 */
 	protected void performApply() {
 		super.performApply();

 		//Apply the default font to the dialog.
 		Font oldFont = appliedDialogFont;

 		FontData[] newData =
 			getFontDataSetting(getDefinition(JFaceResources.DIALOG_FONT));

 		appliedDialogFont = new Font(getControl().getDisplay(), newData);

 		updateForDialogFontChange(appliedDialogFont);
 		getApplyButton().setFont(appliedDialogFont);
 		getDefaultsButton().setFont(appliedDialogFont);

 		if (oldFont != null)
 			oldFont.dispose();

 	}

 }
	package org.eclipse.ui.internal.dialogs;

	/*
	* Copyright (c) 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 java.text.Collator;
	import java.util.ArrayList;
	import java.util.Hashtable;
	import java.util.Iterator;
	import java.util.Set;

	import org.eclipse.jface.preference.IPreferenceStore;
	import org.eclipse.jface.preference.PreferenceConverter;
	import org.eclipse.jface.preference.PreferencePage;
	import org.eclipse.jface.resource.JFaceResources;
	import org.eclipse.jface.resource.StringConverter;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.DisposeEvent;
	import org.eclipse.swt.events.DisposeListener;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Font;
	import org.eclipse.swt.graphics.FontData;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.FontDialog;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.swt.widgets.Text;
	import org.eclipse.swt.widgets.List;
	import org.eclipse.ui.IWorkbench;
	import org.eclipse.ui.IWorkbenchPreferencePage;
	import org.eclipse.ui.help.WorkbenchHelp;
	import org.eclipse.ui.internal.IHelpContextIds;
	import org.eclipse.ui.internal.WorkbenchMessages;
	import org.eclipse.ui.internal.WorkbenchPlugin;
	import org.eclipse.ui.internal.fonts.FontDefinition;
	import org.eclipse.ui.internal.misc.Sorter;

	public class FontPreferencePage
	extends PreferencePage
	implements IWorkbenchPreferencePage {

	private Hashtable labelsToDefinitions;
	private Hashtable fontDataSettings;
	private List fontList;
	private Button changeFontButton;
	private Button useSystemButton;
	private Text descriptionText;
	private Font appliedDialogFont;

	private ArrayList dialogFontWidgets = new ArrayList();

	//A token to identify a reset font
	private String DEFAULT_TOKEN = "DEFAULT";

	/**
	* The label that displays the selected font, or <code>null</code> if none.
	*/
	private Label valueControl;

	/**
	* The previewer, or <code>null</code> if none.
	*/
	private DefaultPreviewer previewer;

	private static class DefaultPreviewer {
	private Text text;
	private Font font;
	public DefaultPreviewer(Composite parent) {
	text = new Text(parent, SWT.READ_ONLY \| SWT.BORDER \| SWT.WRAP);
	text.addDisposeListener(new DisposeListener() {
	public void widgetDisposed(DisposeEvent e) {
	if (font != null)
	font.dispose();
	}
	});
	}

	public Control getControl() {
	return text;
	}

	public void setFont(FontData[] fontData) {
	if (font != null)
	font.dispose();

	FontData[] bestData =
	JFaceResources.getFontRegistry().bestDataArray(
	fontData,
	text.getDisplay());

	//If there are no specified values then return.
	if (bestData == null)
	return;

	font = new Font(text.getDisplay(), bestData);
	text.setFont(font);
	//Also set the text here
	text.setText(WorkbenchMessages.getString("FontsPreference.SampleText")); //$NON-NLS-1$
	}
	public int getPreferredHeight() {
	return 120;
	}
	}

	/**
	* Apply the dialog font to the control and store
	* it for later so that it can be used for a later
	* update.
	* @param control
	*/
	private void applyDialogFont(Control control) {
	control.setFont(JFaceResources.getDialogFont());
	dialogFontWidgets.add(control);
	}

	/**
	* Update for a change in the dialog font.
	* @param newFont
	*/
	private void updateForDialogFontChange(Font newFont) {
	Iterator iterator = dialogFontWidgets.iterator();
	while (iterator.hasNext()) {
	((Control) iterator.next()).setFont(newFont);
	}
	}

	/*
	* @see PreferencePage#createContents
	*/
	public Control createContents(Composite parent) {
	WorkbenchHelp.setHelp(
	getControl(),
	IHelpContextIds.FONT_PREFERENCE_PAGE);

	parent.addDisposeListener(new DisposeListener() {
	public void widgetDisposed(DisposeEvent e) {
	if (appliedDialogFont != null)
	appliedDialogFont.dispose();
	}
	});

	Font defaultFont = parent.getFont();

	Composite mainColumn = new Composite(parent, SWT.NULL);
	GridLayout layout = new GridLayout();
	layout.numColumns = 2;
	layout.marginWidth = 0;
	layout.marginHeight = 0;
	layout.makeColumnsEqualWidth = true;
	mainColumn.setFont(defaultFont);
	mainColumn.setLayout(layout);

	createFontList(mainColumn);

	Composite previewColumn = new Composite(mainColumn, SWT.NULL);
	layout = new GridLayout();
	layout.numColumns = 1;
	layout.marginHeight = 0;
	layout.marginWidth = 0;
	previewColumn.setLayout(layout);
	GridData data = new GridData(GridData.FILL_BOTH);
	data.grabExcessHorizontalSpace = true;
	previewColumn.setLayoutData(data);
	previewColumn.setFont(defaultFont);

	createPreviewControl(previewColumn);
	createValueControl(previewColumn);

	Composite buttonColumn = new Composite(previewColumn, SWT.NULL);
	layout = new GridLayout();
	layout.numColumns = 2;
	layout.marginHeight = 0;
	layout.marginWidth = 0;
	buttonColumn.setLayout(layout);
	data = new GridData(GridData.HORIZONTAL_ALIGN_END);
	buttonColumn.setLayoutData(data);
	buttonColumn.setFont(defaultFont);

	createUseDefaultsControl(buttonColumn, WorkbenchMessages.getString("FontsPreference.useSystemFont")); //$NON-NLS-1$
	createChangeControl(buttonColumn, JFaceResources.getString("openChange")); //$NON-NLS-1$

	createDescriptionControl(parent);

	return mainColumn;
	}

	/**
	* Create the preference page.
	*/
	public FontPreferencePage() {
	setPreferenceStore(WorkbenchPlugin.getDefault().getPreferenceStore());
	}

	/**
	* Create the list of possible fonts.
	*/
	private void createFontList(Composite firstColumn) {

	Composite parent = new Composite(firstColumn, SWT.NULL);
	GridLayout layout = new GridLayout();
	layout.marginWidth = 0;
	layout.marginHeight = 0;
	parent.setLayout(layout);
	GridData data = new GridData(GridData.FILL_BOTH);
	data.grabExcessHorizontalSpace = true;
	parent.setLayoutData(data);

	Label label = new Label(parent, SWT.LEFT);
	label.setText(WorkbenchMessages.getString("FontsPreference.fonts")); //$NON-NLS-1$
	applyDialogFont(label);

	fontList = new List(parent, SWT.BORDER);
	data =
	new GridData(
	GridData.VERTICAL_ALIGN_BEGINNING \| GridData.FILL_BOTH);
	data.grabExcessHorizontalSpace = true;
	fontList.setLayoutData(data);
	applyDialogFont(fontList);

	fontList.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent event) {
	FontDefinition selectedFontDefinition =
	getSelectedFontDefinition();
	if (selectedFontDefinition == null) {
	changeFontButton.setEnabled(false);
	useSystemButton.setEnabled(false);
	} else {
	changeFontButton.setEnabled(true);
	useSystemButton.setEnabled(true);
	updateForSelectedFontDefinition(selectedFontDefinition);
	}
	}
	});

	Set names = labelsToDefinitions.keySet();
	int nameSize = names.size();
	String[] unsortedItems = new String[nameSize];
	names.toArray(unsortedItems);

	Sorter sorter = new Sorter() {
	private Collator collator = Collator.getInstance();

	public boolean compare(Object o1, Object o2) {
	String s1 = (String) o1;
	String s2 = (String) o2;
	return collator.compare(s1, s2) < 0;
	}
	};

	Object[] sortedItems = sorter.sort(unsortedItems);
	String[] listItems = new String[nameSize];
	System.arraycopy(sortedItems, 0, listItems, 0, nameSize);

	fontList.setItems(listItems);
	}

	/**
	* Return the id of the currently selected font. Return
	* null if multiple or none are selected.
	*/

	private FontDefinition getSelectedFontDefinition() {
	String[] selection = fontList.getSelection();
	if (selection.length == 1)
	return (FontDefinition) labelsToDefinitions.get(selection[0]);
	else
	return null;
	}

	/**
	* Creates the change button for this field editor.=
	*/
	private void createChangeControl(
	Composite parent,
	String changeButtonLabel) {
	changeFontButton = new Button(parent, SWT.PUSH);

	changeFontButton.setText(changeButtonLabel); //$NON-NLS-1$
	applyDialogFont(changeFontButton);
	setButtonLayoutData(changeFontButton);

	changeFontButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent event) {
	FontDefinition definition = getSelectedFontDefinition();
	if (definition != null) {
	FontDialog fontDialog =
	new FontDialog(changeFontButton.getShell());
	FontData[] currentData = getFontDataSetting(definition);
	fontDialog.setFontData(currentData[0]);
	FontData font = fontDialog.open();
	if (font != null) {
	FontData[] fonts = new FontData[1];
	fonts[0] = font;
	fontDataSettings.put(definition.getId(), fonts);
	updateForSelectedFontDefinition(definition);
	}

	}

	}
	});

	changeFontButton.setEnabled(false);
	}

	/**
	* Creates the Use System Font button for the editor.
	*/
	private void createUseDefaultsControl(
	Composite parent,
	String useSystemLabel) {

	useSystemButton = new Button(parent, SWT.PUSH \| SWT.CENTER);
	useSystemButton.setText(useSystemLabel); //$NON-NLS-1$
	applyDialogFont(useSystemButton);
	setButtonLayoutData(useSystemButton);

	useSystemButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent event) {
	FontDefinition definition = getSelectedFontDefinition();
	if (definition != null) {
	FontData[] defaultFontData =
	JFaceResources.getDefaultFont().getFontData();
	fontDataSettings.put(definition.getId(), defaultFontData);
	updateForSelectedFontDefinition(definition);
	}
	}
	});

	useSystemButton.setEnabled(false);
	}

	/**
	* Creates the preview control for this field editor.
	*/
	private void createPreviewControl(Composite parent) {
	Label label = new Label(parent, SWT.LEFT);
	label.setText(WorkbenchMessages.getString("FontsPreference.preview")); //$NON-NLS-1$
	applyDialogFont(label);

	previewer = new DefaultPreviewer(parent);
	Control control = previewer.getControl();
	GridData gd = new GridData();
	gd.horizontalAlignment = GridData.FILL;
	gd.grabExcessHorizontalSpace = true;
	gd.heightHint = previewer.getPreferredHeight();
	control.setLayoutData(gd);
	}

	/**
	* Creates the widgets for the description.
	*/
	private void createDescriptionControl(Composite mainComposite) {

	Composite textComposite = new Composite(mainComposite, SWT.NONE);
	textComposite.setLayoutData(new GridData(GridData.FILL_BOTH));
	GridLayout textLayout = new GridLayout();
	textLayout.marginWidth = 0;
	textLayout.marginHeight = 0;
	textComposite.setLayout(textLayout);

	Label descriptionLabel = new Label(textComposite, SWT.NONE);
	descriptionLabel.setText(WorkbenchMessages.getString("FontsPreference.description")); //$NON-NLS-1$
	applyDialogFont(descriptionLabel);

	descriptionText =
	new Text(
	textComposite,
	SWT.MULTI
	\| SWT.WRAP
	\| SWT.READ_ONLY
	\| SWT.BORDER
	\| SWT.H_SCROLL);
	descriptionText.setLayoutData(new GridData(GridData.FILL_BOTH));
	applyDialogFont(descriptionText);
	}

	/**
	* Creates the value control for this field editor. The value control
	* displays the currently selected font name.
	*/
	private void createValueControl(Composite parent) {
	valueControl = new Label(parent, SWT.CENTER);

	valueControl.addDisposeListener(new DisposeListener() {
	public void widgetDisposed(DisposeEvent event) {
	valueControl = null;
	}
	});

	applyDialogFont(valueControl);

	GridData gd =
	new GridData(
	GridData.FILL_HORIZONTAL \| GridData.HORIZONTAL_ALIGN_CENTER);

	gd.grabExcessHorizontalSpace = true;
	valueControl.setLayoutData(gd);
	}

	/**
	* Updates the value label and the previewer to reflect the
	* newly selected font definition.
	* @param FontDefinition
	*/
	private void updateForSelectedFontDefinition(FontDefinition definition) {

	FontData[] font = getFontDataSetting(definition);

	valueControl.setText(StringConverter.asString(font[0]));
	previewer.setFont(font);

	String text = definition.getDescription();
	if (text == null \|\| text.length() == 0)
	descriptionText.setText(WorkbenchMessages.getString("PreferencePage.noDescription")); //$NON-NLS-1$
	else
	descriptionText.setText(text);
	}

	/**
	* Get the current font data setting for the definition.
	* @param definition
	* @return FontData[]
	*/
	private FontData[] getFontDataSetting(FontDefinition definition) {
	String fontId = definition.getId();

	Object setting = fontDataSettings.get(fontId);
	if (DEFAULT_TOKEN.equals(setting))
	return getDefaultFont(definition);
	else
	return (FontData[]) setting;

	}

	/**
	* Return the defualt FontData for the definition.
	* @param definition
	* @return FontData[]
	*/
	private FontData[] getDefaultFont(FontDefinition definition) {

	String defaultsTo = definition.getDefaultsTo();
	if (defaultsTo == null) {
	return PreferenceConverter.getDefaultFontDataArray(
	getPreferenceStore(),
	definition.getId());
	} else {
	FontDefinition defaultDefinition = getDefinition(defaultsTo);
	if (defaultDefinition == null)
	return JFaceResources.getDefaultFont().getFontData();
	else
	return getFontDataSetting(defaultDefinition);
	}
	}

	/*
	* @see IWorkbenchPreferencePage#init
	*/
	public void init(IWorkbench workbench) {

	//Set up the mappings we currently have

	labelsToDefinitions = new Hashtable();
	//Set the user selected values to an empty table
	fontDataSettings = new Hashtable();

	FontDefinition[] definitions = getDefinitions();

	for (int i = 0; i < definitions.length; i++) {
	FontDefinition definition = definitions[i];
	labelsToDefinitions.put(definition.getLabel(), definition);
	Object settingValue;
	if (getPreferenceStore().isDefault(definition.getId()))
	settingValue = DEFAULT_TOKEN;
	else
	settingValue =
	JFaceResources.getFont(definition.getId()).getFontData();
	fontDataSettings.put(definition.getId(), settingValue);
	}

	}

	/*
	* @see IWorkbenchPreferencePage#performDefaults
	*/
	protected void performDefaults() {

	FontDefinition currentSelection = getSelectedFontDefinition();
	FontDefinition[] definitions = getDefinitions();

	for (int i = 0; i < definitions.length; i++) {
	FontDefinition definition = definitions[i];

	//Put an entry of null in to represent the reset
	fontDataSettings.put(definition.getId(), DEFAULT_TOKEN);

	if (definition.equals(currentSelection)) {
	//Now we have the defaults ask the registry which to use of these
	//values
	updateForSelectedFontDefinition(definition);
	}
	}
	super.performDefaults();
	}

	/*
	* @see IWorkbenchPreferencePage#performDefaults
	*/
	public boolean performOk() {

	FontDefinition[] definitions = getDefinitions();
	IPreferenceStore store = getPreferenceStore();
	for (int i = 0; i < definitions.length; i++) {
	FontDefinition definition = definitions[i];
	String preferenceId = definition.getId();
	String registryKey = definition.getId();

	Object setValue = fontDataSettings.get(preferenceId);

	if (DEFAULT_TOKEN.equals(setValue)) {
	store.setToDefault(registryKey);
	} else {
	FontData[] newData = (FontData[]) setValue;
	//Don't update the preference store if there has been no change
	if (!newData
	.equals(
	PreferenceConverter.getFontData(store, registryKey))) {
	PreferenceConverter.setValue(store, registryKey, newData);
	}

	}
	}

	return super.performOk();
	}

	/**
	* Get the font definitions we will be using.
	* @return FontDefinition[]
	*/
	private FontDefinition[] getDefinitions() {
	return FontDefinition.getDefinitions();
	}

	/**
	* Get the FontDefinition with the specified registryKey.
	* @param registryKey
	* @return FontDefinition
	*/
	private FontDefinition getDefinition(String registryKey) {
	FontDefinition[] definitions = getDefinitions();
	for (int i = 0; i < definitions.length; i++) {
	if (definitions[i].getId().equals(registryKey))
	return definitions[i];
	}
	return null;
	}

	/**
	* Return whether the definition has a non default setting.
	* @param definition
	* @return boolean
	*/
	private boolean hasSetting(FontDefinition definition) {
	return fontDataSettings.get(definition.getId()) instanceof FontData[];
	}

	/**
	* @see org.eclipse.jface.preference.PreferencePage#performApply()
	*/
	protected void performApply() {
	super.performApply();

	//Apply the default font to the dialog.
	Font oldFont = appliedDialogFont;

	FontData[] newData =
	getFontDataSetting(getDefinition(JFaceResources.DIALOG_FONT));

	appliedDialogFont = new Font(getControl().getDisplay(), newData);

	updateForDialogFontChange(appliedDialogFont);
	getApplyButton().setFont(appliedDialogFont);
	getDefaultsButton().setFont(appliedDialogFont);

	if (oldFont != null)
	oldFont.dispose();

	}

	}