NFCEmulatorFieldDetector.java

/*
 * NFCEmulatorFieldDetector.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.nfcemulatordemo;

import net.rim.device.api.io.nfc.NFCFieldListener;

/**
 * A class that receives notifications of the presence (or lack thereof) of an
 * NFC field. This listener will only be fired when an emulation is running.
 */
public class NFCEmulatorFieldDetector implements NFCFieldListener {
    private final NFCEmulatorScreen _screen;

    /**
     * Creates a new NFCEmulatorFieldDetector object
     * 
     * @param screen
     *            NFCEmulatorScreen object on which tag information will be
     *            displayed
     * @throws NullPointerException
     *             if screen == null
     */
    public NFCEmulatorFieldDetector(final NFCEmulatorScreen screen) {
        if (screen == null) {
            throw new IllegalArgumentException("screen == null");
        }

        _screen = screen;
    }

    /**
     * @see net.rim.device.api.io.nfc.NFCFieldListener#onFieldChanged(int)
     */
    public void onFieldChanged(final int fieldEvent) {
        // Determine whether an NFC field is present
        switch (fieldEvent) {
        case NFCFieldListener.FIELD_PRESENT:
            _screen.setFieldPresentStatus("Yes");
            break;
        case NFCFieldListener.FIELD_NOT_PRESENT:
            _screen.setFieldPresentStatus("No");
            break;
        }
    }
}