AttachmentDemoScreen.java

/*
 * AttachmentDemoScreen.java
 *
 * Copyright � 1998-2011 Research In Motion Limited
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Note: For the sake of simplicity, this sample application may not leverage
 * resource bundles and resource strings.  However, it is STRONGLY recommended
 * that application developers make use of the localization features available
 * within the BlackBerry development platform to ensure a seamless application
 * experience across a variety of languages and geographies.  For more information
 * on localizing your application, please refer to the BlackBerry Java Development
 * Environment Development Guide associated with this release.
 */

package com.rim.samples.device.attachmentdemo;

import java.io.IOException;

import javax.microedition.io.Connector;
import javax.microedition.io.file.FileConnection;

import net.rim.device.api.command.Command;
import net.rim.device.api.command.CommandHandler;
import net.rim.device.api.command.ReadOnlyCommandMetadata;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.MenuItem;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.Dialog;
import net.rim.device.api.ui.component.LabelField;
import net.rim.device.api.ui.container.MainScreen;
import net.rim.device.api.util.StringProvider;

/**
 * The main screen class for the Attachment Demo sample application
 */
public final class AttachmentDemoScreen extends MainScreen {
    private final LabelField _statusField;
    private final AttachmentAction _action;
    private final UiApplication _app;

    /**
     * Creates a new AttachmentDemoScreen object
     * 
     * @param app
     *            Reference to the UiApplication instance
     */
    public AttachmentDemoScreen(final UiApplication app) {
        _app = app;
        _action = new AttachmentAction(this);

        // Initialize UI
        setTitle("Attachment Demo");
        _statusField =
                new LabelField(
                        "Open the menu to download or upload attachments",
                        Field.NON_FOCUSABLE);
        add(_statusField);
        final MenuItem downloadItem =
                new MenuItem(new StringProvider("Download Attachments"),
                        0x230010, 0);
        downloadItem.setCommand(new Command(new CommandHandler() {
            /**
             * @see net.rim.device.api.command.CommandHandler#execute(ReadOnlyCommandMetadata,
             *      Object)
             */
            public void execute(final ReadOnlyCommandMetadata metadata,
                    final Object context) {
                _statusField.setText("");
                if (_action.getMessages()) {
                    try {
                        _action.download(Dialog.ask(Dialog.D_YES_NO,
                                "Download only png and msword attachments?") == Dialog.NO);
                    } catch (final IOException ex) {
                        AttachmentDemo
                                .errorDialog("DownloadManager.download() threw "
                                        + ex.toString());
                    }
                } else {
                    displayStatus("Mailbox is empty.");
                }
            }
        }));
        final MenuItem uploadItem =
                new MenuItem(new StringProvider("Send Attachment"), 0x230020, 1);
        uploadItem.setCommand(new Command(new CommandHandler() {
            /**
             * @see net.rim.device.api.command.CommandHandler#execute(ReadOnlyCommandMetadata,
             *      Object)
             */
            public void execute(final ReadOnlyCommandMetadata metadata,
                    final Object context) {
                _statusField
                        .setText("Open the menu to download or upload attachments");

                // Check if SD card is inserted
                try {
                    final FileConnection fc =
                            (FileConnection) Connector.open("file:///SDCard/");
                    fc.close();
                    _app.pushScreen(new FileExplorerScreen(_app));
                } catch (final IOException e) {
                    Dialog.inform("Please insert an SD card to upload items.");
                }
            }
        }));
        addMenuItem(downloadItem);
        addMenuItem(uploadItem);
    }

    /**
     * Method to update this screen's status field
     * 
     * @param msg
     *            The text to display
     */
    public void displayStatus(final String msg) {
        _app.invokeLater(new Runnable() {
            public void run() {
                _statusField.setText(_statusField.getText() + '\n' + msg);
            }
        });
    }
}