am df07000e: am d064ce7e: am edb7a442: Merge "docs: Wear DataItem listener improvements" into lmp-docs

* commit 'df07000e356dee84de9f4dcdd22a15e26e32f684':
  docs: Wear DataItem listener improvements
This commit is contained in:
Ricardo Cervera
2015-01-26 19:51:53 +00:00
committed by Android Git Automerger
2 changed files with 113 additions and 28 deletions

View File

@@ -46,7 +46,7 @@ directly. Instead, you:
</ol>
<p>
However, instead of working with raw bytes using <a href="{@docRoot}reference/com/google/android/gms/wearable/PutDataRequest.html#setData(byte[])">setData()</a>,
However, instead of working with raw bytes using <a href="{@docRoot}reference/com/google/android/gms/wearable/PutDataRequest.html#setData(byte[])"><code>setData()</code></a>,
we recommend you <a href="#SyncData">use a data map</a>, which exposes
a data item in an easy-to-use {@link android.os.Bundle}-like interface.
</p>
@@ -88,39 +88,121 @@ app, you should create a path scheme that matches the structure of the data.
</li>
</ol>
<p>The following example shows how to create a data map and put data on it:</p>
<p>The <code>increaseCounter()</code> method in the following example shows how to create a
data map and put data in it:</p>
<pre>
PutDataMapRequest dataMap = PutDataMapRequest.create("/count");
dataMap.getDataMap().putInt(COUNT_KEY, count++);
PutDataRequest request = dataMap.asPutDataRequest();
PendingResult&lt;DataApi.DataItemResult&gt; pendingResult = Wearable.DataApi
.putDataItem(mGoogleApiClient, request);
</pre>
public class MainActivity extends Activity implements
DataApi.DataListener,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener {
<h2 id="ListenEvents">Listen for Data Item Events</h2>
If one side of the data layer connection changes a data item, you probably want
to be notified of any changes on the other side of the connection.
You can do this by implementing a listener for data item events.
private static final String COUNT_KEY = "com.example.key.count";
<p>For example, here's what a typical callback looks like to carry out certain actions
when data changes:</p>
private GoogleApiClient mGoogleApiClient;
private int count = 0;
<pre>
&#64;Override
public void onDataChanged(DataEventBuffer dataEvents) {
for (DataEvent event : dataEvents) {
if (event.getType() == DataEvent.TYPE_DELETED) {
Log.d(TAG, "DataItem deleted: " + event.getDataItem().getUri());
} else if (event.getType() == DataEvent.TYPE_CHANGED) {
Log.d(TAG, "DataItem changed: " + event.getDataItem().getUri());
}
...
// Create a data map and put data in it
private void <strong>increaseCounter</strong>() {
PutDataMapRequest putDataMapReq = PutDataMapRequest.create("/count");
putDataMapReq.getDataMap().putInt(COUNT_KEY, count++);
PutDataRequest putDataReq = putDataMapReq.asPutDataRequest();
PendingResult&lt;DataApi.DataItemResult> pendingResult =
Wearable.DataApi.putDataItem(mGoogleApiClient, putDataReq);
}
...
}
</pre>
<p>
This is just a snippet that requires more implementation details. Learn about
how to implement a full listener service or activity in
<p>For more information about handling the
<a href="{@docRoot}reference/com/google/android/gms/common/api/PendingResult.html">
<code>PendingResult</code></a> object, see
<a href="{@docRoot}training/wearables/data-layer/events.html#Wait">Wait for the Status of Data
Layer Calls</a>.</p>
<h2 id="ListenEvents">Listen for Data Item Events</h2>
<p>If one side of the data layer connection changes a data item, you probably want
to be notified of any changes on the other side of the connection.
You can do this by implementing a listener for data item events.</p>
<p>The code snippet in the following example notifies your app when the value of the
counter defined in the previous example changes:</p>
<pre>
public class MainActivity extends Activity implements
DataApi.DataListener,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener {
private static final String COUNT_KEY = "com.example.key.count";
private GoogleApiClient mGoogleApiClient;
private int count = 0;
&#64;Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(Wearable.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.build();
}
&#64;Override
protected void onResume() {
super.onStart();
mGoogleApiClient.connect();
}
&#64;Override
public void onConnected(Bundle bundle) {
<strong>Wearable.DataApi.addListener</strong>(mGoogleApiClient, this);
}
&#64;Override
protected void onPause() {
super.onPause();
<strong>Wearable.DataApi.removeListener</strong>(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
&#64;Override
public void <strong>onDataChanged</strong>(DataEventBuffer dataEvents) {
for (DataEvent event : dataEvents) {
if (event.getType() == DataEvent.TYPE_CHANGED) {
// DataItem changed
DataItem item = event.getDataItem();
if (item.getUri().getPath().compareTo("/count") == 0) {
DataMap dataMap = DataMapItem.fromDataItem(item).getDataMap();
updateCount(dataMap.getInt(COUNT_KEY));
}
} else if (event.getType() == DataEvent.TYPE_DELETED) {
// DataItem deleted
}
}
}
// Our method to update the count
private void updateCount(int c) { ... }
...
}
</pre>
<p>This activity implements the
<a href="{@docRoot}reference/com/google/android/gms/wearable/DataApi.DataListener.html">
<code>DataItem.DataListener</code></a> interface. This activity adds itself as a listener
for data item events inside the <code>onConnected()</code> method and removes the listener
in the <code>onPause()</code> method.</p>
<p>You can also implement the listener as a service. For more information, see
<a href="{@docRoot}training/wearables/data-layer/events.html#Listen">Listen for Data Layer
Events</a>.
</p>
Events</a>.</p>

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@@ -267,6 +267,8 @@ or <a href="{@docRoot}reference/com/google/android/gms/wearable/NodeApi.html#rem
public class MainActivity extends Activity implements
DataApi.DataListener, ConnectionCallbacks, OnConnectionFailedListener {
private GoogleApiClient mGoogleApiClient;
&#64;Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
@@ -314,4 +316,5 @@ public class MainActivity extends Activity implements
}
}
}
}
</pre>