preferencedialog.java

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/*******************************************************************************
 * Copyright (c) 2000, 2006 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.jface.preference;

import java.io.IOException;
import java.util.Iterator;
import java.util.List;

import org.eclipse.core.runtime.ISafeRunnable;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.dialogs.DialogMessageArea;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.IMessageProvider;
import org.eclipse.jface.dialogs.IPageChangeProvider;
import org.eclipse.jface.dialogs.IPageChangedListener;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.dialogs.PageChangedEvent;
import org.eclipse.jface.dialogs.TrayDialog;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.resource.ImageRegistry;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.util.Assert;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.Policy;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.BusyIndicator;
import org.eclipse.swt.events.ControlAdapter;
import org.eclipse.swt.events.ControlEvent;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.events.HelpEvent;
import org.eclipse.swt.events.HelpListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.ShellAdapter;
import org.eclipse.swt.events.ShellEvent;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FormAttachment;
import org.eclipse.swt.layout.FormData;
import org.eclipse.swt.layout.FormLayout;
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.Event;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Layout;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Sash;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;

/**
 * A preference dialog is a hierarchical presentation of preference pages. Each
 * page is represented by a node in the tree shown on the left hand side of the
 * dialog; when a node is selected, the corresponding page is shown on the right
 * hand side.
 */
public class PreferenceDialog extends TrayDialog implements IPreferencePageContainer, IPageChangeProvider {
	/**
	 * Layout for the page container.
	 *  
	 */
	private class PageLayout extends Layout {
		public Point computeSize(Composite composite, int wHint, int hHint, boolean force) {
			if (wHint != SWT.DEFAULT && hHint != SWT.DEFAULT) {
				return new Point(wHint, hHint);
			}
			int x = minimumPageSize.x;
			int y = minimumPageSize.y;
			Control[] children = composite.getChildren();
			for (int i = 0; i < children.length; i++) {
				Point size = children[i].computeSize(SWT.DEFAULT, SWT.DEFAULT, force);
				x = Math.max(x, size.x);
				y = Math.max(y, size.y);
			}
			
			//As pages can implement thier own computeSize
			//take it into account
			if(currentPage != null){
				Point size = currentPage.computeSize();
				x = Math.max(x, size.x);
				y = Math.max(y, size.y);
			}
			
			if (wHint != SWT.DEFAULT) {
				x = wHint;
			}
			if (hHint != SWT.DEFAULT) {
				y = hHint;
			}
			return new Point(x, y);
		}

		public void layout(Composite composite, boolean force) {
			Rectangle rect = composite.getClientArea();
			Control[] children = composite.getChildren();
			for (int i = 0; i < children.length; i++) {
				children[i].setSize(rect.width, rect.height);
			}
		}
	}

	//The id of the last page that was selected
	private static String lastPreferenceId = null;

	//The last known tree width
	private static int lastTreeWidth = 150;

	/**
	 * Indentifier for the error image
	 */
	public static final String PREF_DLG_IMG_TITLE_ERROR = DLG_IMG_MESSAGE_ERROR;

	/**
	 * Title area fields
	 */
	public static final String PREF_DLG_TITLE_IMG = "preference_dialog_title_image"; //$NON-NLS-1$

	protected static final int FAILED = 2;
	static {
		ImageRegistry reg = JFaceResources.getImageRegistry();
		reg.put(PREF_DLG_TITLE_IMG, ImageDescriptor.createFromFile(PreferenceDialog.class,
				"images/pref_dialog_title.gif")); //$NON-NLS-1$
	}

	/**
	 * The current preference page, or <code>null</code> if there is none.
	 */
	private IPreferencePage currentPage;

	private DialogMessageArea messageArea;

	private Point lastShellSize;

	private IPreferenceNode lastSuccessfulNode;

	/**
	 * The minimum page size; 400 by 400 by default.
	 * 
	 * @see #setMinimumPageSize(Point)
	 */
	private Point minimumPageSize = new Point(400, 400);

	/**
	 * The OK button.
	 */
	private Button okButton;

	/**
	 * The Composite in which a page is shown.
	 */
	private Composite pageContainer;

	/**
	 * The preference manager.
	 */
	private PreferenceManager preferenceManager;

	/**
	 * Flag for the presence of the error message.
	 */
	private boolean showingError = false;

	/**
	 * Preference store, initially <code>null</code> meaning none.
	 * 
	 * @see #setPreferenceStore
	 */
	private IPreferenceStore preferenceStore;

	private Composite titleArea;

	/**
	 * The tree viewer.
	 */
	private TreeViewer treeViewer;
	
    private ListenerList pageChangedListeners = new ListenerList();

    /**
     *  Composite with a FormLayout to contain the title area
     */
    Composite formTitleComposite;

	/**
	 * Creates a new preference dialog under the control of the given preference
	 * manager.
	 * 
	 * @param parentShell
	 *            the parent shell
	 * @param manager
	 *            the preference manager
	 */
	public PreferenceDialog(Shell parentShell, PreferenceManager manager) {
		super(parentShell);
		setShellStyle(getShellStyle() | SWT.RESIZE | SWT.MAX);
		preferenceManager = manager;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.dialogs.Dialog#buttonPressed(int)
	 */
	protected void buttonPressed(int buttonId) {
		switch (buttonId) {
		case IDialogConstants.OK_ID: {
			okPressed();
			return;
		}
		case IDialogConstants.CANCEL_ID: {
			cancelPressed();
			return;
		}
		case IDialogConstants.HELP_ID: {
			helpPressed();
			return;
		}
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.dialogs.Dialog#cancelPressed()
	 */
	protected void cancelPressed() {
		// Inform all pages that we are cancelling
		Iterator nodes = preferenceManager.getElements(PreferenceManager.PRE_ORDER).iterator();
		while (nodes.hasNext()) {
			final IPreferenceNode node = (IPreferenceNode) nodes.next();
			if (getPage(node) != null) {
				SafeRunnable.run(new SafeRunnable() {
					public void run() {
						if (!getPage(node).performCancel()) {
							return;
						}
					}
				});
			}
		}
		setReturnCode(CANCEL);
		close();
	}

	/**
	 * Clear the last selected node. This is so that we not chache the last
	 * selection in case of an error.
	 */
	void clearSelectedNode() {
		setSelectedNodePreference(null);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.window.Window#close()
	 */
	public boolean close() {
		List nodes = preferenceManager.getElements(PreferenceManager.PRE_ORDER);
		for (int i = 0; i < nodes.size(); i++) {
			IPreferenceNode node = (IPreferenceNode) nodes.get(i);
			node.disposeResources();
		}
		return super.close();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.window.Window#configureShell(org.eclipse.swt.widgets.Shell)
	 */
	protected void configureShell(Shell newShell) {
		super.configureShell(newShell);
		newShell.setText(JFaceResources.getString("PreferenceDialog.title")); //$NON-NLS-1$
		newShell.addShellListener(new ShellAdapter() {
			public void shellActivated(ShellEvent e) {
				if (lastShellSize == null) {
					lastShellSize = getShell().getSize();
				}
			}

		});

	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.window.Window#constrainShellSize()
	 */
	protected void constrainShellSize() {
		super.constrainShellSize();
		// record opening shell size
		if (lastShellSize == null) {
			lastShellSize = getShell().getSize();
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.dialogs.Dialog#createButtonsForButtonBar(org.eclipse.swt.widgets.Composite)
	 */
	protected void createButtonsForButtonBar(Composite parent) {
		// create OK and Cancel buttons by default
		okButton = createButton(parent, IDialogConstants.OK_ID, IDialogConstants.OK_LABEL, true);
		getShell().setDefaultButton(okButton);
		createButton(parent, IDialogConstants.CANCEL_ID, IDialogConstants.CANCEL_LABEL, false);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.window.Window#createContents(org.eclipse.swt.widgets.Composite)
	 */
	protected Control createContents(final Composite parent) {
		final Control[] control = new Control[1];
		BusyIndicator.showWhile(getShell().getDisplay(), new Runnable() {
			public void run() {
				control[0] = PreferenceDialog.super.createContents(parent);
				// Add the first page
				selectSavedItem();
			}
		});

		return control[0];
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.dialogs.Dialog#createDialogArea(org.eclipse.swt.widgets.Composite)
	 */
	protected Control createDialogArea(Composite parent) {
		final Composite composite = (Composite) super.createDialogArea(parent);
		GridLayout parentLayout = ((GridLayout) composite.getLayout());
		parentLayout.numColumns = 4;
		parentLayout.marginHeight = 0;
		parentLayout.marginWidth = 0;
		parentLayout.verticalSpacing = 0;
		parentLayout.horizontalSpacing = 0;
		
		composite.setBackground(parent.getDisplay().getSystemColor(SWT.COLOR_LIST_BACKGROUND));
		
		Control treeControl = createTreeAreaContents(composite);
		createSash(composite,treeControl);
		
		Label versep = new Label(composite, SWT.SEPARATOR | SWT.VERTICAL);
		GridData verGd = new GridData(GridData.FILL_VERTICAL | GridData.GRAB_VERTICAL);
	
		versep.setLayoutData(verGd);
		versep.setLayoutData(new GridData(SWT.LEFT, SWT.FILL, false, true));
		
		Composite pageAreaComposite = new Composite(composite, SWT.NONE);
		pageAreaComposite.setLayoutData(new GridData(GridData.FILL_BOTH));
		GridLayout layout = new GridLayout(1, true);
		layout.marginHeight = 0;
		layout.marginWidth = 0;
		layout.verticalSpacing = 0;
		pageAreaComposite.setLayout(layout);
		
		formTitleComposite = new Composite(pageAreaComposite, SWT.NONE);
		FormLayout titleLayout = new FormLayout();
		titleLayout.marginWidth = 0;
		titleLayout.marginHeight = 0;
		formTitleComposite.setLayout(titleLayout);
		
		GridData titleGridData = new GridData(GridData.FILL_HORIZONTAL);
		titleGridData.horizontalIndent = IDialogConstants.HORIZONTAL_MARGIN;
		formTitleComposite.setLayoutData(titleGridData);
		
		// Build the title area and separator line
		Composite titleComposite = new Composite(formTitleComposite, SWT.NONE);
		layout = new GridLayout();
		layout.marginBottom = 5;
		layout.marginHeight = 0;
		layout.marginWidth = 0;
		layout.horizontalSpacing = 0;
		titleComposite.setLayout(layout);
		
		FormData titleFormData = new FormData();
	   	titleFormData.top = new FormAttachment(0,0);
    	titleFormData.left = new FormAttachment(0,0);
    	titleFormData.right = new FormAttachment(100,0);
    	titleFormData.bottom = new FormAttachment(100,0);
		
		titleComposite.setLayoutData(titleFormData);
		createTitleArea(titleComposite);
		
		Label separator = new Label(pageAreaComposite, SWT.HORIZONTAL | SWT.SEPARATOR);

		separator.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.GRAB_HORIZONTAL));
		
		
		// Build the Page container
		pageContainer = createPageContainer(pageAreaComposite);
		GridData pageContainerData = new GridData(GridData.FILL_BOTH);
		pageContainerData.horizontalIndent = IDialogConstants.HORIZONTAL_MARGIN;
		pageContainer.setLayoutData(pageContainerData);
		// Build the separator line
		Label bottomSeparator = new Label(parent, SWT.HORIZONTAL | SWT.SEPARATOR);
		bottomSeparator.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.GRAB_HORIZONTAL));
		return composite;
	}

	/**
	 * Create the sash with right control on the right. Note 
	 * that this method assumes GridData for the layout data
	 * of the rightControl.
	 * @param composite
	 * @param rightControl
	 * @return Sash
	 * 
	 * @since 3.1
	 */
	protected Sash createSash(final Composite composite, final Control rightControl) {
		final Sash sash = new Sash(composite, SWT.VERTICAL);
		sash.setLayoutData(new GridData(GridData.FILL_VERTICAL));
		sash.setBackground(composite.getDisplay().getSystemColor(SWT.COLOR_LIST_BACKGROUND));
		// the following listener resizes the tree control based on sash deltas.
		// If necessary, it will also grow/shrink the dialog.
		sash.addListener(SWT.Selection, new Listener() {
			/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.swt.widgets.Listener#handleEvent(org.eclipse.swt.widgets.Event)
			 */
			public void handleEvent(Event event) {
				if (event.detail == SWT.DRAG) {
					return;
				}
				int shift = event.x - sash.getBounds().x;
				GridData data = (GridData) rightControl.getLayoutData();
				int newWidthHint = data.widthHint + shift;
				if (newWidthHint < 20) {
					return;
				}
				Point computedSize = getShell().computeSize(SWT.DEFAULT, SWT.DEFAULT);
				Point currentSize = getShell().getSize();
				// if the dialog wasn't of a custom size we know we can shrink
				// it if necessary based on sash movement.
				boolean customSize = !computedSize.equals(currentSize);
				data.widthHint = newWidthHint;
				setLastTreeWidth(newWidthHint);
				composite.layout(true);
				// recompute based on new widget size
				computedSize = getShell().computeSize(SWT.DEFAULT, SWT.DEFAULT);
				// if the dialog was of a custom size then increase it only if
				// necessary.
				if (customSize) {
					computedSize.x = Math.max(computedSize.x, currentSize.x);
				}
				computedSize.y = Math.max(computedSize.y, currentSize.y);
				if (computedSize.equals(currentSize)) {
					return;
				}
				setShellSize(computedSize.x, computedSize.y);
				lastShellSize = getShell().getSize();
			}
		});
		return sash;
	}