Midi plumbing refactoring

The reverse channel from the SynthesizerService to the views has been
refactored a bit so it's just a standard MidiListener interface rather
than a whole bunch of listeners for individual messages.

android/src/com/levien/synthesizer/android/service/SynthesizerService.java

@@ -41,7 +41,7 @@ import android.util.Log;
 import com.levien.synthesizer.R;
 import com.levien.synthesizer.android.AndroidGlue;
 import com.levien.synthesizer.android.usb.UsbMidiDevice;
-import com.levien.synthesizer.core.midi.MessageForwarder;
+import com.levien.synthesizer.core.midi.MessageTee;
 import com.levien.synthesizer.core.midi.MidiListener;
 import com.levien.synthesizer.core.model.composite.MultiChannelSynthesizer;
 
@@ -100,31 +100,7 @@ public class SynthesizerService extends Service {
         Log.e(getClass().getName(), "loading patches failed");
       }
     }
-    midiListener_ = new MessageForwarder(androidGlue_) {
-      @Override
-      public void onController(int channel, int control, int value) {
-        super.onController(channel, control, value);
-        if (onCcListener_!= null) {
-          onCcListener_.onCcChange(channel, control, value);
-        }
-      }
-
-      @Override
-      public void onNoteOn(int channel, int note, int velocity) {
-        super.onNoteOn(channel, note, velocity);
-        if (onNoteOnListener_ != null) {
-          onNoteOnListener_.onNote(channel, note, velocity);
-        }
-      }
-
-      @Override
-      public void onNoteOff(int channel, int note, int velocity) {
-        super.onNoteOff(channel, note, velocity);
-        if (onNoteOffListener_ != null) {
-          onNoteOffListener_.onNote(channel, note, velocity);
-        }
-      }
-    };
+    midiListener_ = new MessageTee(androidGlue_);
     androidGlue_.setPlayState(true);
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1) {
       IntentFilter filter = new IntentFilter(UsbManager.ACTION_USB_DEVICE_DETACHED);
@@ -288,25 +264,11 @@ public class SynthesizerService extends Service {
     }
   };
 
-  // There's a pretty good case to be made this should just tee a MidiListener instead
-  public interface OnCcListener {
-    abstract void onCcChange(int channel, int cc, int value);
-  }
-
-  public interface OnNoteListener {
-    abstract void onNote(int channel, int note, int velocity);
-  }
-
-  public void setOnCcListener(OnCcListener onCcListener) {
-    onCcListener_ = onCcListener;
-  }
-
-  public void setOnNoteListeners(OnNoteListener onNoteOn, OnNoteListener onNoteOff) {
-    onNoteOnListener_ = onNoteOn;
-    onNoteOffListener_ = onNoteOff;
+  public void setMidiListener(MidiListener target) {
+    midiListener_.setSecondTarget(target);
   }
 
-  private MidiListener midiListener_;
+  private MessageTee midiListener_;
 
   // Binder to use for Activities in this process.
   private final IBinder binder_ = new LocalBinder();
@@ -322,8 +284,4 @@ public class SynthesizerService extends Service {
   private UsbInterface usbMidiInterface_;
   private UsbDevice usbDeviceNeedsPermission_;
 
-  // Plumbing for MIDI events
-  private OnCcListener onCcListener_;
-  private OnNoteListener onNoteOnListener_;
-  private OnNoteListener onNoteOffListener_;
 }

android/src/com/levien/synthesizer/android/ui/PianoActivity2.java

@@ -16,7 +16,6 @@
 
 package com.levien.synthesizer.android.ui;
 
-import java.util.HashMap;
 import java.util.List;
 
 import android.annotation.TargetApi;
@@ -29,8 +28,6 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.ServiceConnection;
 import android.hardware.usb.UsbDevice;
-import android.hardware.usb.UsbDeviceConnection;
-import android.hardware.usb.UsbInterface;
 import android.hardware.usb.UsbManager;
 import android.os.Build;
 import android.os.Bundle;
@@ -45,10 +42,11 @@ import android.widget.Spinner;
 
 import com.levien.synthesizer.R;
 import com.levien.synthesizer.android.service.SynthesizerService;
-import com.levien.synthesizer.android.usb.UsbMidiDevice;
 import com.levien.synthesizer.android.widgets.knob.KnobListener;
 import com.levien.synthesizer.android.widgets.knob.KnobView;
 import com.levien.synthesizer.android.widgets.piano.PianoView;
+import com.levien.synthesizer.core.midi.MidiAdapter;
+import com.levien.synthesizer.core.midi.MidiListener;
 
 /**
  * Activity for simply playing the piano.
@@ -70,44 +68,6 @@ public class PianoActivity2 extends Activity {
     overdriveKnob_ = (KnobView)findViewById(R.id.overdriveKnob);
     presetSpinner_ = (Spinner)findViewById(R.id.presetSpinner);
 
-    presetSpinner_.setOnItemSelectedListener(new OnItemSelectedListener() {
-      public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
-        if (synthesizerService_ != null) {
-          synthesizerService_.getMidiListener().onProgramChange(0, position);
-        }
-      }
-      public void onNothingSelected(AdapterView<?> parent) {
-      }
-    });
-
-    cutoffKnob_.setKnobListener(new KnobListener() {
-      public void onKnobChanged(double newValue) {
-        // Maybe actually bind these at synthesizer service connection time?
-        if (synthesizerService_ != null) {
-          int value = (int)Math.round(newValue * 127);
-          synthesizerService_.getMidiListener().onController(0, 1, value);
-        }
-      }
-    });
-    resonanceKnob_.setKnobListener(new KnobListener() {
-      public void onKnobChanged(double newValue) {
-        if (synthesizerService_ != null) {
-          int value = (int)Math.round(newValue * 127);
-          synthesizerService_.getMidiListener().onController(0, 2, value);
-        }
-      }
-    });
-    overdriveKnob_.setKnobListener(new KnobListener() {
-      public void onKnobChanged(double newValue) {
-        if (synthesizerService_ != null) {
-          int value = (int)Math.round(newValue * 127);
-          synthesizerService_.getMidiListener().onController(0, 3, value);
-        }
-      }
-    });
-
-    //piano_.bindTo(synthesizerService_.getMidiListener());
-
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1) {
       setupUsbMidi(getIntent());
     }
@@ -212,71 +172,108 @@ public class PianoActivity2 extends Activity {
     public void onServiceConnected(ComponentName className, IBinder service) {
       SynthesizerService.LocalBinder binder = (SynthesizerService.LocalBinder)service;
       synthesizerService_ = binder.getService();
-      piano_.bindTo(synthesizerService_.getMidiListener());
+      onSynthConnected();
+    }
+    public void onServiceDisconnected(ComponentName className) {
+      onSynthDisconnected();
+      synthesizerService_ = null;
+    }
+  };
 
-      // Populate patch names (note: we could update an existing list rather than
-      // creating a new adapter, but it probably wouldn't save all that much).
-      List<String> patchNames = synthesizerService_.getPatchNames();
-      ArrayAdapter<String> adapter = new ArrayAdapter<String>(
-              PianoActivity2.this, android.R.layout.simple_spinner_item, patchNames);
-      adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
-      presetSpinner_.setAdapter(adapter);
+  @TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
+  private void onSynthConnected() {
+    final MidiListener synthMidi = synthesizerService_.getMidiListener();
+    piano_.bindTo(synthMidi);
 
-      // Handle any pending USB device events
-      if (usbDevicePending_ != null) {
-        synthesizerService_.connectUsbMidi(usbDevicePending_);
-        usbDevicePending_ = null;
-      } else {
-        UsbDevice device = synthesizerService_.usbDeviceNeedsPermission();
-        if (device != null) {
-          synchronized (usbReceiver_) {
-            if (!permissionRequestPending_) {
-              permissionRequestPending_ = true;
-              UsbManager usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
-              usbManager.requestPermission(device, permissionIntent_);
-            }
+    cutoffKnob_.setKnobListener(new KnobListener() {
+      public void onKnobChanged(double newValue) {
+        int value = (int)Math.round(newValue * 127);
+        synthMidi.onController(0, 1, value);
+      }
+    });
+    resonanceKnob_.setKnobListener(new KnobListener() {
+      public void onKnobChanged(double newValue) {
+        int value = (int)Math.round(newValue * 127);
+        synthMidi.onController(0, 2, value);
+      }
+    });
+    overdriveKnob_.setKnobListener(new KnobListener() {
+      public void onKnobChanged(double newValue) {
+        int value = (int)Math.round(newValue * 127);
+        synthMidi.onController(0, 3, value);
+      }
+    });
+
+    // Connect controller changes to knob views
+    synthesizerService_.setMidiListener(new MidiAdapter() {
+      public void onNoteOn(final int channel, final int note, final int velocity) {
+        runOnUiThread(new Runnable() {
+          public void run() {
+            piano_.setNoteOn(note, true);
           }
-        }
+        });
       }
 
-      // Connect controller changes to knob views
-      synthesizerService_.setOnCcListener(new SynthesizerService.OnCcListener() {
-        public void onCcChange(final int channel, final int cc, final int value) {
-          runOnUiThread(new Runnable() {
-            public void run() {
-              if (cc == 1) {
-                cutoffKnob_.setValue(value * (1.0 / 127));
-              } else if (cc == 2) {
-                resonanceKnob_.setValue(value * (1.0 / 127));
-              } else if (cc == 3) {
-                overdriveKnob_.setValue(value * (1.0 / 127));
-              }
-            }
-          });
-        }
-      });
-      synthesizerService_.setOnNoteListeners(new SynthesizerService.OnNoteListener() {
-        public void onNote(final int channel, final int note, final int velocity) {
-          runOnUiThread(new Runnable() {
-            public void run() {
-              piano_.setNoteOn(note, true);
-            }
-          });
-        }
-      }, new SynthesizerService.OnNoteListener() {
-        public void onNote(final int channel, final int note, final int velocity) {
-          runOnUiThread(new Runnable() {
-            public void run() {
-              piano_.setNoteOn(note, false);
+      public void onNoteOff(final int channel, final int note, final int velocity) {
+        runOnUiThread(new Runnable() {
+          public void run() {
+            piano_.setNoteOn(note, false);
+          }
+        });
+      }
+
+      public void onController(final int channel, final int cc, final int value) {
+        runOnUiThread(new Runnable() {
+          public void run() {
+            if (cc == 1) {
+              cutoffKnob_.setValue(value * (1.0 / 127));
+            } else if (cc == 2) {
+              resonanceKnob_.setValue(value * (1.0 / 127));
+            } else if (cc == 3) {
+              overdriveKnob_.setValue(value * (1.0 / 127));
             }
-          });
+          }
+        });
+      }
+    });
+
+    // Populate patch names (note: we could update an existing list rather than
+    // creating a new adapter, but it probably wouldn't save all that much).
+    List<String> patchNames = synthesizerService_.getPatchNames();
+    ArrayAdapter<String> adapter = new ArrayAdapter<String>(
+            PianoActivity2.this, android.R.layout.simple_spinner_item, patchNames);
+    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
+    presetSpinner_.setAdapter(adapter);
+
+    presetSpinner_.setOnItemSelectedListener(new OnItemSelectedListener() {
+      public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
+        synthesizerService_.getMidiListener().onProgramChange(0, position);
+      }
+      public void onNothingSelected(AdapterView<?> parent) {
+      }
+    });
+
+    // Handle any pending USB device events
+    if (usbDevicePending_ != null) {
+      synthesizerService_.connectUsbMidi(usbDevicePending_);
+      usbDevicePending_ = null;
+    } else {
+      UsbDevice device = synthesizerService_.usbDeviceNeedsPermission();
+      if (device != null) {
+        synchronized (usbReceiver_) {
+          if (!permissionRequestPending_) {
+            permissionRequestPending_ = true;
+            UsbManager usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
+            usbManager.requestPermission(device, permissionIntent_);
+          }
         }
-      });
-    }
-    public void onServiceDisconnected(ComponentName className) {
-      synthesizerService_ = null;
+      }
     }
-  };
+  }
+
+  private void onSynthDisconnected() {
+    synthesizerService_.setMidiListener(null);
+  }
 
   private SynthesizerService synthesizerService_;
 

core/src/com/levien/synthesizer/core/midi/MessageTee.java

@@ -17,102 +17,172 @@
 package com.levien.synthesizer.core.midi;
 
 /**
- * Class for forwarding messages to another MidiListener. Great for subclassing.
+ * Duplicate each MIDI message to two listeners
  */
-public class MessageForwarder implements MidiListener {
-  public MessageForwarder(MidiListener target) {
+public class MessageTee implements MidiListener {
+  public MessageTee(MidiListener target) {
     target_ = target;
   }
 
+  public void setSecondTarget(MidiListener target) {
+    target2_ = target;
+  }
+
   // Control events.
   public void onNoteOff(int channel, int note, int velocity) {
     target_.onNoteOff(channel, note, velocity);
+    if (target2_ != null) {
+      target2_.onNoteOff(channel, note, velocity);
+    }
   }
 
   public void onNoteOn(int channel, int note, int velocity) {
     target_.onNoteOn(channel, note, velocity);
+    if (target2_ != null) {
+      target2_.onNoteOn(channel, note, velocity);
+    }
   }
 
   public void onNoteAftertouch(int channel, int note, int aftertouch) {
     target_.onNoteAftertouch(channel, note, aftertouch);
+    if (target2_ != null) {
+      target2_.onNoteAftertouch(channel, note, aftertouch);
+    }
   }
 
   public void onController(int channel, int control, int value) {
     target_.onController(channel, control, value);
+    if (target2_ != null) {
+      target2_.onController(channel, control, value);
+    }
   }
 
   public void onProgramChange(int channel, int program) {
     target_.onProgramChange(channel, program);
+    if (target2_ != null) {
+      target2_.onProgramChange(channel, program);
+    }
   }
 
   public void onChannelAftertouch(int channel, int aftertouch) {
     target_.onChannelAftertouch(channel, aftertouch);
+    if (target2_ != null) {
+      target2_.onChannelAftertouch(channel, aftertouch);
+    }
   }
 
   public void onPitchBend(int channel, int value) {
     target_.onPitchBend(channel, value);
+    if (target2_ != null) {
+      target2_.onPitchBend(channel, value);
+    }
   }
 
   // Other events.
   public void onTimingClock() {
     target_.onTimingClock();
+    if (target2_ != null) {
+      target2_.onTimingClock();
+    }
   }
 
   public void onActiveSensing() {
     target_.onActiveSensing();
+    if (target2_ != null) {
+      target2_.onActiveSensing();
+    }
   }
 
   // Meta events.
   public void onSequenceNumber(int sequenceNumber) {
     target_.onSequenceNumber(sequenceNumber);
+    if (target2_ != null) {
+      target2_.onSequenceNumber(sequenceNumber);
+    }
   }
 
   public void onText(byte[] text) {
     target_.onText(text);
+    if (target2_ != null) {
+      target2_.onText(text);
+    }
   }
 
   public void onCopyrightNotice(byte[] text) {
     target_.onCopyrightNotice(text);
+    if (target2_ != null) {
+      target2_.onCopyrightNotice(text);
+    }
   }
 
   public void onSequenceName(byte[] text) {
     target_.onSequenceName(text);
+    if (target2_ != null) {
+      target2_.onSequenceName(text);
+    }
   }
 
   public void onInstrumentName(byte[] text) {
     target_.onInstrumentName(text);
+    if (target2_ != null) {
+      target2_.onInstrumentName(text);
+    }
   }
 
   public void onLyrics(byte[] text) {
     target_.onLyrics(text);
+    if (target2_ != null) {
+      target2_.onLyrics(text);
+    }
   }
 
   public void onMarker(byte[] text) {
     target_.onMarker(text);
+    if (target2_ != null) {
+      target2_.onMarker(text);
+    }
   }
 
   public void onCuePoint(byte[] text) {
     target_.onCuePoint(text);
+    if (target2_ != null) {
+      target2_.onCuePoint(text);
+    }
   }
 
   public void onChannelPrefix(int channel) {
     target_.onChannelPrefix(channel);
+    if (target2_ != null) {
+      target2_.onChannelPrefix(channel);
+    }
   }
 
   public void onPort(byte[] data) {
     target_.onPort(data);
+    if (target2_ != null) {
+      target2_.onPort(data);
+    }
   }
 
   public void onEndOfTrack() {
     target_.onEndOfTrack();
+    if (target2_ != null) {
+      target2_.onEndOfTrack();
+    }
   }
 
   public void onSetTempo(int microsecondsPerQuarterNote) {
     target_.onSetTempo(microsecondsPerQuarterNote);
+    if (target2_ != null) {
+      target2_.onSetTempo(microsecondsPerQuarterNote);
+    }
   }
 
   public void onSmpteOffset(byte[] data) {
     target_.onSmpteOffset(data);
+    if (target2_ != null) {
+      target2_.onSmpteOffset(data);
+    }
   }
 
   public void onTimeSignature(int numerator,
@@ -121,20 +191,34 @@ public class MessageForwarder implements MidiListener {
                        int thirtySecondNotesPerQuarterNote) {
     target_.onTimeSignature(numerator, denominator, metronomePulse,
             thirtySecondNotesPerQuarterNote);
+    if (target2_ != null) {
+      target2_.onTimeSignature(numerator, denominator, metronomePulse,
+              thirtySecondNotesPerQuarterNote);
+    }
   }
 
   public void onKeySignature(int key, boolean isMinor) {
     target_.onKeySignature(key, isMinor);
+    if (target2_ != null) {
+      target2_.onKeySignature(key, isMinor);
+    }
   }
 
   public void onSequencerSpecificEvent(byte[] data) {
     target_.onSequencerSpecificEvent(data);
+    if (target2_ != null) {
+      target2_.onSequencerSpecificEvent(data);
+    }
   }
 
   // SysEx events.
   public void onSysEx(byte[] data) {
     target_.onSysEx(data);
+    if (target2_ != null) {
+      target2_.onSysEx(data);
+    }
   }
 
-  private MidiListener target_;
+  private final MidiListener target_;
+  private MidiListener target2_;
 }