最新的Android Wear更新随附对ChannelApi的支持，可用于向可穿戴设备或手持设备发送文件或从可穿戴设备或手持设备发送文件。问题是我找不到如何使用此功能的单个示例。 Android示例不包含此功能。因此，如果有人知道如何使用sendFile / receiveFile并可以在此处给出一个简单的示例，将不胜感激。
查看此answer，了解如何使用Channel API在设备之间创建通道。
创建googleClient并检索要将文件发送到的设备的nodeId之后，基本上，您可以在可穿戴设备上使用以下代码：
//opening channel
ChannelApi.OpenChannelResult result = Wearable.ChannelApi.openChannel(googleClient, nodeId, "/mypath").await();
channel = result.getChannel();
//sending file
channel.sendFile(googleClient, Uri.fromFile(file));
然后，在手持设备上：
//receiving the file
@Override
public void onChannelOpened(Channel channel) {
if (channel.getPath().equals("/mypath")) {
file = new File("/sdcard/file.txt");
try {
file.createNewFile();
} catch (IOException e) {
//handle error
}
channel.receiveFile(mGoogleApiClient, Uri.fromFile(file), false);
}
}
//when file is ready
@Override
public void onInputClosed(Channel channel, int i, int i1) {
MainActivity.this.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(MainActivity.this, "File received!", Toast.LENGTH_SHORT).show();
}
});
}
如果需要有关此信息的更多信息，请访问reference site from Google
这只是对答案的补充：还要在androidmanifest中检查您的WearableListenerService。它的意图过滤器应包含com.google.android.gms.wearable.CHANNEL_EVENT操作。
我已经成功使用了一些这样的代码。传输可能相当慢。
手持式和可穿戴式应用程序在其gradle文件中都必须具有相同的applicationId。 可穿戴设备需要清单条目，例如：
<service
android:name="com.me.myWearableListenerService"
android:enabled="true"
android:exported="true">
<intent-filter>
<!-- listeners receive events that match the action and data filters -->
<action android:name="com.google.android.gms.wearable.CHANNEL_EVENT"/>
<data android:scheme="wear" android:host="*" android:pathPrefix="/MyAppPath" />
</intent-filter>
</service>
在手持设备发送文件时启动其WearableListenerService。
private static final String WEARABLE_FILE_COPY = "MyAppPath/FileCopy";
private void copyFileToWearable (final File file, final String nodeId, Context ctx) {
new Thread(new Runnable() {
@Override
public void run() {
final ChannelClient cc = Wearable.getChannelClient(ctx);
ChannelClient.ChannelCallback ccb = new ChannelClient.ChannelCallback() {
@Override
public void onChannelClosed(@NonNull ChannelClient.Channel channel, int i, int i1) {
super.onChannelClosed(channel, i, i1);
Log.d(TAG, "copyFileToWearable " + channel.getNodeId() + " onChannelClosed ");
cc.unregisterChannelCallback(this);
}
@Override
public void onOutputClosed(@NonNull ChannelClient.Channel channel, int i, int i1) {
super.onOutputClosed(channel, i, i1);
Log.d(TAG, "copyFileToWearable " + channel.getNodeId() + " onOutputClosed ");
cc.unregisterChannelCallback(this);
// this is transfer success callback ...
}
};
ChannelClient.Channel c;
Log.d(TAG, "copyFileToWearable transfer file " + file.getName() +
" size:" + file.length()/1000000 + "Mb");
try {
// send the filename to the wearable with the channel open
c = Tasks.await(cc.openChannel(nodeId, WEARABLE_FILE_COPY + "/" + file.getName()));
Log.d(TAG, "copyFileToWearable channel opened to " + nodeId);
Log.d(TAG, "copyFileToWearable register callback");
Tasks.await(cc.registerChannelCallback(c, ccb));
Log.d(TAG, "copyFileToWearable sending file " + file.getName());
Tasks.await(cc.sendFile(c, Uri.fromFile(file)));
// completion is indicated by onOutputClosed
} catch (Exception e) {
Log.w(TAG, "copyFileToWearable exception " + e.getMessage());
cc.unregisterChannelCallback(ccb);
// failure
}
}
}).start();
}
当c.getPath（）以WEARABLE_FILE_COPY开头时从WearableListenerService中的onChannelOpened调用
private void receiveFileFromHandheld(final ChannelClient.Channel c, File myStorageLocation, Context ctx) {
// filename sent by the handheld is at the end of the path
String[] bits = c.getPath().split("\\/");
// store in a suitable spot
final String receivedFileName = myStorageLocation.getAbsolutePath() + "/" + bits[bits.length-1];
new Thread(new Runnable() {
@Override
public void run() {
final ChannelClient cc = Wearable.getChannelClient(ctx);
ChannelClient.ChannelCallback ccb = new ChannelClient.ChannelCallback() {
boolean mClosed = false;
@Override
public void onChannelClosed(@NonNull ChannelClient.Channel channel, int i, int i1) {
super.onChannelClosed(channel, i, i1);
Log.d(TAG, "receiveFileFromHandheld " + channel.getNodeId() + " onChannelClosed ");
if (!mClosed){
// failure ...
}
}
@Override
public void onInputClosed(@NonNull ChannelClient.Channel channel, int i, int i1) {
super.onInputClosed(channel, i, i1);
Log.d(TAG, "receiveFileFromHandheld " + channel.getNodeId() + " onInputClosed ");
long fs = new File(receivedFileName).length();
Log.d(TAG, "receiveFileFromHandheld got " + receivedFileName +
" size:" + fs / 1000000 + "Mb");
cc.unregisterChannelCallback(this);
mClosed = true;
// success !
}
};
try {
Log.d(TAG, "receiveFileFromHandheld register callback");
Tasks.await(cc.registerChannelCallback(c, ccb));
Log.d(TAG, "receiveFileFromHandheld receiving file " + receivedFileName);
Tasks.await(cc.receiveFile(c, Uri.fromFile(new File(receivedFileName)), false));
// completion is indicated by onInputClosed
} catch (Exception e) {
Log.w(TAG, "receiveFileFromHandheld exception " + e.getMessage());
cc.unregisterChannelCallback(ccb);
// failure ...
}
}
}
).start();
}