org.eclipse.help.ui/src/org/eclipse/help/internal/ui/ContextHelpDialog.java

package org.eclipse.help.internal.ui;
/*
 * (c) Copyright IBM Corp. 2000, 2002.
 * All Rights Reserved.
 */
import org.eclipse.help.*;
import org.eclipse.help.internal.ui.util.WorkbenchResources;
import org.eclipse.help.internal.util.Logger;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;
import org.eclipse.ui.help.WorkbenchHelp;
/**
 * ContextHelpDialog
 */
public class ContextHelpDialog {
	private Color backgroundColour = null;
	private IContext context;
	private Color foregroundColour = null;
	private Color linkColour = null;
	private static HyperlinkHandler linkManager = new HyperlinkHandler();
	private Shell shell;
	/**
	 * Constructor:
	 * @param context an array of String or an array of IContext
	 * @param x the x mouse location in the current display
	 * @param y the y mouse location in the current display
	 */
	ContextHelpDialog(IContext context, int x, int y) {
		this.context = context;
		Display display = Display.getCurrent();
		backgroundColour = display.getSystemColor(SWT.COLOR_INFO_BACKGROUND);
		foregroundColour = display.getSystemColor(SWT.COLOR_INFO_FOREGROUND);
		linkColour = display.getSystemColor(SWT.COLOR_BLUE);
		shell = new Shell(display.getActiveShell(), SWT.NONE);
		if (Logger.DEBUG)
			Logger.logDebugMessage(
				"ContextHelpDialog",
				" Constructor: Shell is:" + shell.toString());
		WorkbenchHelp.setHelp(shell, IHelpUIConstants.F1_SHELL);
		shell.addListener(SWT.Deactivate, new Listener() {
			public void handleEvent(Event e) {
				if (Logger.DEBUG)
					Logger.logDebugMessage(
						"ContextHelpDialog",
						"handleEvent: SWT.Deactivate called. ");
				close();
			};
		});
		shell.addControlListener(new ControlAdapter() {
			public void controlMoved(ControlEvent e) {
				if (Logger.DEBUG)
					Logger.logDebugMessage("ContextHelpDialog", "controlMoved: called. ");
				Rectangle clientArea = shell.getClientArea();
				shell.redraw(
					clientArea.x,
					clientArea.y,
					clientArea.width,
					clientArea.height,
					true);
				shell.update();
			}
		});
		if (Logger.DEBUG)
			Logger.logDebugMessage(
				"ContextHelpDialog",
				"Constructor: Focus owner is: "
					+ Display.getCurrent().getFocusControl().toString());
		linkManager.setHyperlinkUnderlineMode(HyperlinkHandler.UNDERLINE_ROLLOVER);
		createContents(shell);
		shell.pack();
		// Correct x and y of the shell if it not contained within the screen
		int width = shell.getBounds().width;
		int height = shell.getBounds().height;
		// check lower boundaries
		x = x >= 0 ? x : 0;
		y = y >= 0 ? y : 0;
		// check upper boundaries
		int margin = 0;
		if (System.getProperty("os.name").startsWith("Win"))
			margin = 28; // for the Windows task bar in the ussual place;
		Rectangle screen = display.getBounds();
		x = x + width <= screen.width ? x : screen.width - width;
		y = y + height <= screen.height - margin ? y : screen.height - margin - height;
		shell.setLocation(x, y);
	}
	public synchronized void close() {
		try {
			if (Logger.DEBUG)
				Logger.logDebugMessage("ContextHelpDialog", "close: called. ");
			if (shell != null) {
				shell.close();
				if (!shell.isDisposed())
					shell.dispose();
				shell = null;
			}
		} catch (Throwable ex) {
		}
	}
	protected Control createContents(Composite contents) {
		contents.setBackground(backgroundColour);
		GridLayout layout = new GridLayout();
		layout.marginHeight = 5;
		layout.marginWidth = 5;
		contents.setLayout(layout);
		contents.setLayoutData(new GridData(GridData.FILL_BOTH));
		// create the dialog area and button bar
		createInfoArea(contents);
		createLinksArea(contents);
		return contents;
	}
	private Control createInfoArea(Composite parent) {
		// Create the text field.    
		String styledText = context.getText();
		if (styledText == null) // no description found in context objects.
			styledText = WorkbenchResources.getString("WW002");
		StyledText text =
			new StyledText(parent, SWT.MULTI | SWT.READ_ONLY | SWT.NO_FOCUS /* | SWT.WRAP*/
		);
		text.getCaret().setVisible(false);
		text.setBackground(backgroundColour);
		text.setForeground(foregroundColour);
		StyledLineWrapper content = new StyledLineWrapper(styledText);
		text.setContent(content);
		text.setStyleRanges(content.getStyles());
		return text;
	}
	private Control createLink(Composite parent, IHelpResource topic) {
		Label image = new Label(parent, SWT.NONE);
		image.setImage(ElementLabelProvider.getDefault().getImage(topic));
		image.setBackground(backgroundColour);
		GridData data = new GridData();
		data.horizontalAlignment = data.HORIZONTAL_ALIGN_BEGINNING;
		data.verticalAlignment = data.VERTICAL_ALIGN_BEGINNING;
		//data.horizontalIndent = 4;
		image.setLayoutData(data);
		Label link = new Label(parent, SWT.NONE);
		link.setText(topic.getLabel());
		link.setBackground(backgroundColour);
		link.setForeground(linkColour);
		data = new GridData();
		data.horizontalAlignment = data.HORIZONTAL_ALIGN_BEGINNING;
		data.verticalAlignment = data.VERTICAL_ALIGN_BEGINNING;
		link.setLayoutData(data);
		linkManager.registerHyperlink(link, new LinkListener(topic));
		return link;
	}
	private Control createLinksArea(Composite parent) {
		IHelpResource[] relatedTopics = context.getRelatedTopics();
		if (relatedTopics == null)
			return null;
		// Create control
		Composite composite = new Composite(parent, SWT.NONE);
		composite.setBackground(backgroundColour);
		GridLayout layout = new GridLayout();
		layout.marginHeight = 2;
		layout.marginWidth = 0;
		layout.verticalSpacing = 3;
		layout.horizontalSpacing = 2;
		layout.numColumns = 2;
		composite.setLayout(layout);
		GridData data =
			new GridData(
				GridData.FILL_BOTH
					| GridData.HORIZONTAL_ALIGN_BEGINNING
					| GridData.VERTICAL_ALIGN_CENTER);
		composite.setLayoutData(data);
		// Create separator.    
		Label label = new Label(composite, SWT.SEPARATOR | SWT.HORIZONTAL);
		label.setBackground(backgroundColour);
		label.setForeground(foregroundColour);
		data =
			new GridData(
				GridData.HORIZONTAL_ALIGN_BEGINNING
					| GridData.VERTICAL_ALIGN_BEGINNING
					| GridData.FILL_HORIZONTAL);
		data.horizontalSpan = 2;
		label.setLayoutData(data);
		// Create related links
		for (int i = 0; i < relatedTopics.length; i++) {
			createLink(composite, relatedTopics[i]);
		}
		return composite;
	}
	/**
	 * Called when related link has been chosen
	 * Opens help viewer with list of all related topics
	 */
	private void launchLinks(IHelpResource selectedTopic) {
		close();
		if (Logger.DEBUG)
			Logger.logDebugMessage("ContextHelpDialog", "launchLinks: closes shell");
		// launch help view
		DefaultHelp.getInstance().displayHelp(context, selectedTopic);
	}
	public synchronized void open() {
		try {
			shell.open();
			if (Logger.DEBUG)
				Logger.logDebugMessage(
					"ContextHelpDialog",
					"open: Focus owner after open is: "
						+ Display.getCurrent().getFocusControl().toString());
		} catch (Throwable e) {
		}
	}
	class LinkListener extends HyperlinkAdapter {
		IHelpResource topic;
		public LinkListener(IHelpResource topic) {
			this.topic = topic;
		}
		public void linkActivated(Control c) {
			launchLinks(topic);
		}
	}
}