Trying to run MIDI on my Android app. I'm following the midisuite example to configure my app and it works fine with the exception of aftertouch. Whenever I try to trigger aftertouch, I run into a threading exception type
InteruptedException. How should I prevent this threading issue? My knowledge on multithreading isn't the best or else I would've figured this out already. All I can really tell right now is that the message is sending too fast and the thread hasn't woken up yet from its sleep call.
I followed the github repo with my code as follows:
MidiReceiver subclass:
@TargetApi(Build.VERSION_CODES.M)
public class MidiEngine extends MidiReceiver {
public AudioActivity activity;
private MidiEventScheduler eventScheduler;
private MidiFramer midiFramer;
private MidiReceiver midiReceiver = new MyReceiver();
private Thread mThread;
private boolean go;
private int mProgram;
public MidiEngine() {
this(new AudioActivity());
}
public MidiEngine(AudioActivity activity) {
this.activity = activity;
midiReceiver = new MyReceiver();
midiFramer = new MidiFramer(midiReceiver);
}
public AudioActivity getActivity() {
return this.activity;
}
/* This will be called when MIDI data arrives. */
@Override
public void onSend(byte[] data, int offset, int count, long timestamp)
throws IOException {
if (eventScheduler != null) {
if (!MidiConstants.isAllActiveSensing(data, offset, count)) {
eventScheduler.getReceiver().send(data, offset, count,
timestamp);
}
}
}
// Custom Listener to send to correct methods
private class MyReceiver extends MidiReceiver {
@Override
public void onSend(byte[] msg, int offset, int count, long timestamp) throws IOException {
byte command = (byte)(msg[0] & MidiConstants.STATUS_COMMAND_MASK);
int channel = (byte)(msg[0] & MidiConstants.STATUS_CHANNEL_MASK);
switch (command) {
case MidiConstants.STATUS_NOTE_ON:
activity.keyDown(i, msg[1], msg[2]);
break;
case MidiConstants.STATUS_NOTE_OFF:
activity.keyUp(channel, msg[1]);
break;
case MidiConstants.STATUS_POLYPHONIC_AFTERTOUCH:
activity.keyDown(channel, msg[1], msg[2]);
break;
case MidiConstants.STATUS_PITCH_BEND:
activity.pitchBendAction(channel, (msg[2] << 7) + msg[1]);
break;
case MidiConstants.STATUS_CONTROL_CHANGE:
activity.ccAction(channel, msg[1], msg[2]);
break;
case MidiConstants.STATUS_PROGRAM_CHANGE:
mProgram = msg[1];
break;
default:
break;
}
}
}
class MyRunnable implements Runnable {
@Override
public void run() {
do {
try {
activity.runOnUiThread(new Runnable() {
@Override
public void run() {
try {
processMidiEvents();
}
catch (Exception e) {
Log.e("Java", "SynthEngine background thread exception.", e);
}
}
});
Thread.sleep(100);
}
catch (InterruptedException e) {
Log.e("Java", "Threading exception", e);
}
}
while (go);
}
}
/**
* @throws IOException
*
*/
private void processMidiEvents() throws IOException {
long now = System.nanoTime();
MidiEventScheduler.MidiEvent event = (MidiEventScheduler.MidiEvent) eventScheduler.getNextEvent(now);
while (event != null) {
midiFramer.send(event.data, 0, event.count, event.getTimestamp());
eventScheduler.addEventToPool(event);
event = (MidiEventScheduler.MidiEvent) eventScheduler.getNextEvent(now);
}
}
public void start() {
stop();
go = true;
mThread = new Thread(new MyRunnable());
mThread.setPriority(6);
eventScheduler = new MidiEventScheduler();
mThread.start();
}
public void stop() {
go = false;
if (mThread != null) {
try {
mThread.interrupt();
mThread.join(500);
}
catch (Exception e) {
}
mThread = null;
eventScheduler = null;
}
}
}
Stack Trace Error (line 154 refers to the Thread.sleep part in my custom Runnable class):
Java: Threading exception
java.lang.InterruptedException
at java.lang.Thread.sleep(Native Method)
at java.lang.Thread.sleep(Thread.java:1031)
at java.lang.Thread.sleep(Thread.java:985)
at com.rfoo.midiapp.communication.MidiEngineInput$MyRunnable.run(MidiEngineInput.java:154)
at java.lang.Thread.run(Thread.java:818)
Thanks!
EDIT: Thread start
Midi Device Service subclass (thread will start whenever a device has connected or disconnected).
@TargetApi(Build.VERSION_CODES.M)
public class MidiSynthDeviceService extends MidiDeviceService {
private static final String TAG = "MidiSynthDeviceService";
private boolean midiStarted = false;
@Override
public void onCreate() {
super.onCreate();
}
@Override
public void onDestroy() {
AudioActivity.midiEngine.stop();
super.onDestroy();
}
@Override
// Declare the receivers associated with your input ports.
public MidiReceiver[] onGetInputPortReceivers() {
return new MidiReceiver[] { AudioActivity.midiEngine };
}
/**
* This will get called when clients connect or disconnect.
* You can use it to turn on your synth only when needed.
*/
@Override
public void onDeviceStatusChanged(MidiDeviceStatus status) {
if (status.isInputPortOpen(0) && !midiStarted) {
AudioActivity.midiEngine.start();
midiStarted = true;
} else if (!status.isInputPortOpen(0) && midiStarted){
AudioActivity.midiEngine.stop();
midiStarted = false;
}
}
}
Activity class:
public class AudioActivity extends AppCompatActivity {
private Thread thread;
public static MidiEngine midiEngine;
@Override
protected void onCreate(Bundle savedInstanceState) {
// Layout inits
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
// Setup MIDI:
if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_MIDI)) {
Toast.makeText(this, "MIDI not supported!", Toast.LENGTH_LONG).show();
}
else {
midiEngine = new MidiEngine(this);
setupMidi();
}
// Setup audio thread:
if (thread == null) {
thread = new Thread() {
public void run() {
setPriority(Thread.MAX_PRIORITY);
// Runs an Open SL audio thread (C++)
// This generates a waveform.
// AudioEngine is a wrapper class connecting C++ to Java
AudioEngine.runProcess();
}
}
}
}
public void setupMidi() {
if (activity == null) activity = (AudioActivity) getContext();
mMidiManager = (MidiManager) activity.getSystemService(AudioActivity.MIDI_SERVICE);
if (mMidiManager == null) {
Toast.makeText(activity, "MidiManager is null!", Toast.LENGTH_LONG).show();
return;
}
// Get Device Info
MidiDeviceInfo deviceInfo = MidiTools.findDevice(mMidiManager, "RFOO", "AudioApp");
// MIDI Input
portIndex = 0;
inputPortSelector = new MidiOutputPortConnectionSelector(mMidiManager, activity, R.id
.inputListView, deviceInfo, portIndex);
inputPortSelector.setConnectedListener(new MyPortsConnectedListener());
midi_ch_input = 0;
midi_ch_output = 0;
}
// Bunch of UI code here....
}
