Examples with TagLostException android.nfc.TagLostException used on opensource projects

Example 6 with TagLostException

use of android.nfc.TagLostException in project android_frameworks_base by crdroidandroid.

the class Ndef method getNdefMessage.

/**
     * Read the current {@link android.nfc.NdefMessage} on this tag.
     *
     * <p>This always reads the current NDEF Message stored on the tag.
     *
     * <p>Note that this method may return null if the tag was in the
     * INITIALIZED state as defined by NFC Forum, as in that state the
     * tag is formatted to support NDEF but does not contain a message yet.
     *
     * <p>This is an I/O operation and will block until complete. It must
     * not be called from the main application thread. A blocked call will be canceled with
     * {@link IOException} if {@link #close} is called from another thread.
     *
     * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission.
     *
     * @return the NDEF Message, can be null
     * @throws TagLostException if the tag leaves the field
     * @throws IOException if there is an I/O failure, or the operation is canceled
     * @throws FormatException if the NDEF Message on the tag is malformed
     */
public NdefMessage getNdefMessage() throws IOException, FormatException {
    checkConnected();
    try {
        INfcTag tagService = mTag.getTagService();
        if (tagService == null) {
            throw new IOException("Mock tags don't support this operation.");
        }
        int serviceHandle = mTag.getServiceHandle();
        if (tagService.isNdef(serviceHandle)) {
            NdefMessage msg = tagService.ndefRead(serviceHandle);
            if (msg == null && !tagService.isPresent(serviceHandle)) {
                throw new TagLostException();
            }
            return msg;
        } else if (!tagService.isPresent(serviceHandle)) {
            throw new TagLostException();
        } else {
            return null;
        }
    } catch (RemoteException e) {
        Log.e(TAG, "NFC service dead", e);
        return null;
    }
}