| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * 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.example.android.beamlargefiles; |
| |
| import android.app.Activity; |
| import android.net.Uri; |
| import android.nfc.NfcAdapter; |
| import android.nfc.NfcEvent; |
| import android.os.Bundle; |
| import android.support.v4.app.Fragment; |
| import android.util.Log; |
| |
| /** |
| * This class demonstrates how to use Beam to send files too large to transfer reliably via NFC. |
| * |
| * <p>While any type of data can be placed into a normal NDEF messages, NFC is not considered |
| * "high-speed" communication channel. Large images can easily take > 30 seconds to transfer. |
| * Because NFC requires devices to be in extremely close proximity, this is not ideal. |
| * |
| * <p>Instead, Android 4.2+ devices can use NFC to perform an initial handshake, before handing |
| * off to a faster communication channel, such as Bluetooth, for file transfer. |
| * |
| * <p>The tradeoff is that this application will not be invoked on the receiving device. Instead, |
| * the transfer will be handled by the OS. The user will be shown a notification when the transfer |
| * is complete. Selecting the notification will open the file in the default viewer for its MIME- |
| * type. (If it's important that your application be used to open the file, you'll need to register |
| * an intent-filter to watch for the appropriate MIME-type.) |
| */ |
| public class BeamLargeFilesFragment extends Fragment implements NfcAdapter.CreateBeamUrisCallback { |
| |
| private static final String TAG = "BeamLargeFilesFragment"; |
| /** Filename that is to be sent for this activity. Relative to /assets. */ |
| private static final String FILENAME = "stargazer_droid.jpg"; |
| /** Content provider URI. */ |
| private static final String CONTENT_BASE_URI = |
| "content://com.example.android.beamlargefiles.files/"; |
| |
| /** |
| * Standard lifecycle event. Registers a callback for large-file transfer, by calling |
| * NfcAdapter.setBeamPushUrisCallback(). |
| * |
| * Note: Like sending NDEF messages over standard Android Beam, there is also a non-callback |
| * API available. See: NfcAdapter.setBeamPushUris(). |
| * |
| * @param savedInstanceState Saved instance state. |
| */ |
| @Override |
| public void onCreate(Bundle savedInstanceState) { |
| super.onCreate(savedInstanceState); |
| setHasOptionsMenu(true); |
| Activity a = getActivity(); |
| |
| // Setup Beam to transfer a large file. Note the call to setBeamPushUrisCallback(). |
| // BEGIN_INCLUDE(setBeamPushUrisCallback) |
| NfcAdapter nfc = NfcAdapter.getDefaultAdapter(a); |
| if (nfc != null) { |
| Log.w(TAG, "NFC available. Setting Beam Push URI callback"); |
| nfc.setBeamPushUrisCallback(this, a); |
| } else { |
| Log.w(TAG, "NFC is not available"); |
| } |
| // END_INCLUDE(setBeamPushUrisCallback) |
| } |
| |
| /** |
| * Callback for Beam events (large file version). The return value here should be an array of |
| * content:// or file:// URIs to send. |
| * |
| * Note that the system must have read access to whatever URIs are provided here. |
| * |
| * @param nfcEvent NFC event which triggered callback |
| * @return URIs to be sent to remote device |
| */ |
| // BEGIN_INCLUDE(createBeamUris) |
| @Override |
| public Uri[] createBeamUris(NfcEvent nfcEvent) { |
| Log.i(TAG, "Beam event in progress; createBeamUris() called."); |
| // Images are served using a content:// URI. See AssetProvider for implementation. |
| Uri photoUri = Uri.parse(CONTENT_BASE_URI + FILENAME); |
| Log.i(TAG, "Sending URI: " + photoUri); |
| return new Uri[] {photoUri}; |
| } |
| // END_INCLUDE(createBeamUris) |
| } |