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TextRecord class for the NFC Reader tutorial
/*
* Copyright (C) 2010 The Android Open Source Project
* Modified by Sylvain Saurel for a tutorial
*
* 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.
*/
package com.ssaurel.nfcreader.record;
import android.app.Activity;
import android.nfc.NdefRecord;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import com.google.common.base.Preconditions;
import com.ssaurel.nfcreader.R;
import com.ssaurel.nfcreader.model.History;
import java.io.UnsupportedEncodingException;
import java.util.Arrays;
/**
* An NFC Text Record
*/
public class TextRecord implements ParsedNdefRecord {
/** ISO/IANA language code */
private final String mLanguageCode;
private final String mText;
public TextRecord(String languageCode, String text) {
mLanguageCode = Preconditions.checkNotNull(languageCode);
mText = Preconditions.checkNotNull(text);
}
public String str() {
return mText;
}
public String getText() {
return mText;
}
/**
* Returns the ISO/IANA language code associated with this text element.
*/
public String getLanguageCode() {
return mLanguageCode;
}
// TODO: deal with text fields which span multiple NdefRecords
public static TextRecord parse(NdefRecord record) {
Preconditions.checkArgument(record.getTnf() == NdefRecord.TNF_WELL_KNOWN);
Preconditions.checkArgument(Arrays.equals(record.getType(), NdefRecord.RTD_TEXT));
try {
byte[] payload = record.getPayload();
/*
* payload[0] contains the "Status Byte Encodings" field, per the
* NFC Forum "Text Record Type Definition" section 3.2.1.
*
* bit7 is the Text Encoding Field.
*
* if (Bit_7 == 0): The text is encoded in UTF-8 if (Bit_7 == 1):
* The text is encoded in UTF16
*
* Bit_6 is reserved for future use and must be set to zero.
*
* Bits 5 to 0 are the length of the IANA language code.
*/
String textEncoding = ((payload[0] & 0200) == 0) ? "UTF-8" : "UTF-16";
int languageCodeLength = payload[0] & 0077;
String languageCode = new String(payload, 1, languageCodeLength, "US-ASCII");
String text =
new String(payload, languageCodeLength + 1,
payload.length - languageCodeLength - 1, textEncoding);
return new TextRecord(languageCode, text);
} catch (UnsupportedEncodingException e) {
// should never happen unless we get a malformed tag.
throw new IllegalArgumentException(e);
}
}
public static boolean isText(NdefRecord record) {
try {
parse(record);
return true;
} catch (IllegalArgumentException e) {
return false;
}
}
}
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