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Commit 3cc1bdbc authored by Phil Burk's avatar Phil Burk
Browse files

MIDI docs BTLE: how to open BTLE MIDI devices 



Adds crucial information including required permissions,
MIDI UUID, and call to openBluetoothDevice().

Bug: 22606182
Change-Id: I47393bd0ecc2601906f6e50075d694c9cc17c993
Signed-off-by: default avatarPhil Burk <philburk@google.com>
parent b83b5fa6

media/java/android/media/midi/package.html

+50 −1
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ capabilities, etc.</li> 
  <li> Timestamps to avoid jitter.</li>

  <li> Support creation of <em>virtual MIDI devices</em> that can be connected to other devices.

  An example might be a synthesizer app that can be controlled by a composing app.</li>

  <li> Support direction connection or &ldquo;patching&rdquo; of devices for lower latency.</li>

  <li> Support direct connection or &ldquo;patching&rdquo; of devices for lower latency.</li>

</ul>



<h2 id=transports_supported>Transports Supported</h2>
@@ -338,5 +338,54 @@ public class MidiSynthDeviceService extends MidiDeviceService { 
    }

}

</pre>



<h1 id=using_midi_btle>Using MIDI Over Bluetooth LE</h1>



<p>MIDI devices can be connected to Android using Bluetooth LE.</p>



<p>Before using the device, the app must scan for available BTLE devices and then allow

the user to connect. An example program

will be provided so look for it on the Android developer website.</p>



<h2 id=btle_location_permissions>Request Location Permission for BTLE</h2>



<p>Applications that scan for Bluetooth devices must request permission in the

manifest file. This LOCATION permission is required because it may be possible to

guess the location of an Android device by seeing which BTLE devices are nearby.</p>



<pre class=prettyprint>

&lt;uses-permission android:name="android.permission.BLUETOOTH"/>

&lt;uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>

&lt;uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

</pre>



<p>Apps must also request location permission from the user at run-time.

See the documentation for <code>Activity.requestPermissions()</code> for details and an example.

</p>



<h2 id=btle_scan_devices>Scan for MIDI Devices</h2>



<p>The app will only want to see MIDI devices and not mice or other non-MIDI devices.

So construct a ScanFilter using the UUID for standard MIDI over BTLE.</p>



<pre class=prettyprint>

MIDI over BTLE UUID = "03B80E5A-EDE8-4B33-A751-6CE34EC4C700"

</pre>



<h2 id=btle_open_device>Open a MIDI Bluetooth Device</h2>



<p>See the documentation for <code>android.bluetooth.le.BluetoothLeScanner.startScan()</code>

method for details. When the user selects a MIDI/BTLE device then you can open it

using the MidiManager.</p>



<pre class=prettyprint>

m.openBluetoothDevice(bluetoothDevice, callback, handler);

</pre>



<p>Once the MIDI/BTLE device has been opened by one app then it will also become available to other

apps using the

<a href="#get_list_of_already_plugged_in_entities">MIDI device discovery calls described above</a>.

</p>



</body>

</html>