HelpView.java

/*******************************************************************************
 * Copyright (c) 2011-2012 Nokia Corporation
 * 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:
 * Comarch team - initial API and implementation
 *******************************************************************************/
package org.ned.client.view;

import com.sun.lwuit.events.ActionEvent;
import com.sun.lwuit.events.ActionListener;
import com.sun.lwuit.html.HTMLComponent;
import com.sun.lwuit.layouts.BorderLayout;
import java.io.IOException;
import java.io.InputStream;
import java.util.Hashtable;
import javax.microedition.io.file.FileConnection;
import org.ned.client.NedResources;
import org.ned.client.command.BackHelpCommand;
import org.ned.client.lwuitExtended.NedRequestHandler;

public class HelpView extends NedFormBase implements ActionListener {

    private HTMLComponent comp = null;
    private Class caller = null;
    private Object params = null;
    private final static Hashtable classNames = new Hashtable();

    static {
        classNames.put( CategoryScreen.class, "CategoryScreen" );
        classNames.put( CatalogScreen.class, "CatalogScreen" );
        classNames.put( DownloadQueueScreen.class, "DownloadQueueScreen" );
        classNames.put( DownloadOptionScreen.class, "DownloadOptionScreen" );
        classNames.put( StatisticsOptionScreen.class, "StatisticsOptionScreen" );
        classNames.put( StatisticsScreen.class, "StatisticsScreen" );
        classNames.put( WelcomeScreen.class, "WelcomeScreen" );
        classNames.put( LoginScreen.class, "LoginScreen" );
        classNames.put( MediaItemsScreen.class, "MediaItemsScreen" );
        classNames.put( SettingsScreen.class, "SettingsScreen" );
        classNames.put( HistoryScreen.class, "HistoryScreen" );
        classNames.put( LibraryManagerScreen.class, "LibraryManagerScreen" );
        classNames.put( MainScreen.class, "MainScreen" );
        classNames.put( LanguagesScreen.class, "LanguagesScreen" );
        classNames.put( ShowTipsConfigView.class, "ShowTipsConfigView" );
        classNames.put( SortingMediaItemMethodView.class, "SortingMediaItemMethodView" );
    }

    public HelpView( Object aParam ) {

        if ( aParam instanceof Class ) {
            caller = (Class)aParam;
        } else {
            Object[] params = (Object[])aParam;
            caller = (Class)params[0];
        }
        params = aParam;

        String viewName = getViewNameByClass( caller );
        String text = getHelpText( viewName );

        setLayout( new BorderLayout() );
        setNedTitle( "Help for " + viewName );
        setScrollable( false );

        comp = new HTMLComponent( new NedRequestHandler() );
        comp.setShowImages( true );
        comp.setScrollableX( false );
        comp.setScrollableY( true );
        comp.setBodyText( text );

        addComponent( BorderLayout.CENTER, comp );
        addCommand( BackHelpCommand.getInstance().getCommand() );
        addCommandListener( this );
    }

    public void actionPerformed( ActionEvent evt ) {
        Object src = evt.getSource();
        if ( src == BackHelpCommand.getInstance().getCommand() ) {
            comp.cancel();
            BackHelpCommand.getInstance().execute( params );
        }
    }

    private String getHelpText( String caller ) {
        FileConnection fc = null;
        InputStream is = null;
        StringBuffer sb = null;

        String fileName = "/org/ned/client/help/".concat( caller );
        Class clazz = Runtime.getRuntime().getClass();

        try {
            is = clazz.getResourceAsStream( fileName );
            sb = new StringBuffer();
            int chars = 0;
            while ( (chars = is.read()) != -1 ) {
                sb.append( (char)chars );
            }
        } catch ( IOException ex ) {
            ex.printStackTrace();  // TODO?
        } catch ( OutOfMemoryError ex ) {
            GeneralAlert.show( NedResources.MEMORY_OUT, GeneralAlert.WARNING );
        } finally {
            try {
                is.close();
            } catch ( Exception ex ) {
            }
            try {
                fc.close();
            } catch ( Exception ex ) {
            }
        }
        return sb.toString();
    }

    private String getViewNameByClass( Class caller ) {
        return (String)classNames.get( caller );
    }
}