Add simple settings screen

The first setting is just the keyboard layout, but we'll add lots more
in time (velocity sensitivity). Plus, some synth state (program change
in particular) should persist, and this is a good mechanism.

There are some infelicities: the settings screen doesn't bind the synth
service, so sound pauses. Also, fullscreen is inconsistent and should be
rethought (maybe immersive on KitKat).

android/AndroidManifest.xml

@@ -75,6 +75,9 @@
         android:name="com.levien.synthesizer.android.ui.KarplusStrongActivity"
         android:label="@string/karplus_strong"
         android:screenOrientation="landscape" />
+    <activity
+        android:name="com.levien.synthesizer.android.ui.SettingsActivity"
+        android:label="@string/settings" />
     <service android:name=".android.service.SynthesizerService">
     </service>
   </application>

android/res/values/strings.xml

@@ -83,4 +83,16 @@
 
   <string name="settings">Settings</string>
 
+  <!-- Preferences -->
+  <string name="pref_keyboardType">Keyboard Type</string>
+  <string-array name="pref_keyboardType_entries">
+      <item>2 Level (Piano)</item>
+      <item>3 Level</item>
+  </string-array>
+  <string-array name="pref_keyboardType_values">
+      <item>2level</item>
+      <item>3level</item>
+  </string-array>
+  <string name="pref_keyboardType_default">2level</string>
+
 </resources>

android/res/xml/preferences.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+	<ListPreference
+		android:key="keyboard_type"
+		android:title="@string/pref_keyboardType"
+		android:entries="@array/pref_keyboardType_entries"
+		android:entryValues="@array/pref_keyboardType_values"
+		android:defaultValue="@string/pref_keyboardType_default" />
+</PreferenceScreen>

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

@@ -24,12 +24,16 @@ import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.content.SharedPreferences;
+import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
 import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbManager;
 import android.os.Build;
 import android.os.Bundle;
+import android.preference.PreferenceManager;
 import android.util.Log;
 import android.view.Menu;
+import android.view.MenuItem;
 import android.view.View;
 import android.view.WindowManager;
 import android.widget.AdapterView;
@@ -51,7 +55,7 @@ import com.levien.synthesizer.core.midi.MidiListener;
  * This version is hacked up to send MIDI to the C++ engine. This needs to
  * be refactored to make it cleaner.
  */
-public class PianoActivity2 extends SynthActivity {
+public class PianoActivity2 extends SynthActivity implements OnSharedPreferenceChangeListener {
   @Override
   public void onCreate(Bundle savedInstanceState) {
     Log.d("synth", "activity onCreate " + getIntent());
@@ -60,9 +64,7 @@ public class PianoActivity2 extends SynthActivity {
             WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
     setContentView(R.layout.piano2);
 
-    //piano_ = (PianoView)findViewById(R.id.piano);
     keyboard_ = (KeyboardView)findViewById(R.id.piano);
-    keyboard_.setKeyboardSpec(KeyboardSpec.make2Layer());
     ScrollStripView scrollStrip_ = (ScrollStripView)findViewById(R.id.scrollstrip);
     scrollStrip_.bindKeyboard(keyboard_);
     cutoffKnob_ = (KnobView)findViewById(R.id.cutoffKnob);
@@ -81,6 +83,16 @@ public class PianoActivity2 extends SynthActivity {
     return true;
   }
 
+  @Override
+  public boolean onOptionsItemSelected(MenuItem item) {
+    switch (item.getItemId()) {
+      case R.id.settings:
+        startActivity(new Intent(this, SettingsActivity.class));
+        return true;
+      default:
+        return super.onOptionsItemSelected(item);
+    }
+  }
   @Override
   protected void onDestroy() {
     Log.d("synth", "activity onDestroy");
@@ -90,16 +102,31 @@ public class PianoActivity2 extends SynthActivity {
     super.onDestroy();
   }
 
+  @Override
+  protected void onResume() {
+    super.onResume();
+    SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
+    prefs.registerOnSharedPreferenceChangeListener(this);
+    onSharedPreferenceChanged(prefs, "keyboard_type");
+  }
+
   @Override
   protected void onPause() {
-    Log.d("synth", "activity onPause");
     super.onPause();
+    SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
+    prefs.unregisterOnSharedPreferenceChangeListener(this);
+
   }
 
-  @Override
-  protected void onResume() {
-    Log.d("synth", "activity onResume " + getIntent());
-    super.onResume();
+  public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
+    if (key.equals("keyboard_type")) {
+      String keyboardType = prefs.getString(key, "2level");
+      if (keyboardType.equals("2level")) {
+        keyboard_.setKeyboardSpec(KeyboardSpec.make2Layer());
+      } else if (keyboardType.equals("3level")) {
+        keyboard_.setKeyboardSpec(KeyboardSpec.make3Layer());
+      }
+    }
   }
 
   @Override
@@ -222,11 +249,16 @@ public class PianoActivity2 extends SynthActivity {
 
     // 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);
+    if (presetSpinner_.getAdapter() == null) {
+      // Only set it once, which is a workaround that allows the preset
+      // selection to persist for onCreate lifetime. Of course, it should
+      // be persisted for real, instead.
+      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) {

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

@@ -0,0 +1,15 @@
+package com.levien.synthesizer.android.ui;
+
+import android.os.Bundle;
+import android.preference.PreferenceActivity;
+
+import com.levien.synthesizer.R;
+
+public class SettingsActivity extends PreferenceActivity {
+  @Override
+  public void onCreate(Bundle savedInstanceState) {
+    super.onCreate(savedInstanceState);
+    addPreferencesFromResource(R.xml.preferences);
+  }
+}
+

android/src/com/levien/synthesizer/android/widgets/keyboard/ScrollStripView.java

@@ -83,8 +83,7 @@ public class ScrollStripView extends View {
 
   @Override
   public boolean onTouchEvent(MotionEvent event) {
-    int action = event.getAction();
-    int actionCode = action & MotionEvent.ACTION_MASK;
+    int actionCode = event.getActionMasked();
     boolean redraw = false;
     if (actionCode == MotionEvent.ACTION_DOWN) {
       int pointerId = event.getPointerId(0);
@@ -92,8 +91,7 @@ public class ScrollStripView extends View {
         redraw = onTouchDown(pointerId, event.getX());
       }
     } else if (actionCode == MotionEvent.ACTION_POINTER_DOWN) {
-      int pointerIndex = (action & MotionEvent.ACTION_POINTER_INDEX_MASK)
-              >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;
+      int pointerIndex = event.getActionIndex();
       int pointerId = event.getPointerId(pointerIndex);
       if (pointerId < 2 && pointerId >= 0) {
         redraw = onTouchDown(pointerId, event.getX(pointerIndex));
@@ -104,8 +102,7 @@ public class ScrollStripView extends View {
         onTouchUp(pointerId);
       }
     } else if (actionCode == MotionEvent.ACTION_POINTER_UP) {
-      int pointerIndex = (action & MotionEvent.ACTION_POINTER_INDEX_MASK)
-              >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;
+      int pointerIndex = event.getActionIndex();
       int pointerId = event.getPointerId(pointerIndex);
       if (pointerId < 2 && pointerId >= 0) {
         onTouchUp(pointerId);
@@ -126,8 +123,9 @@ public class ScrollStripView extends View {
       } else if (touchDown_[0] && touchDown_[1]) {
         zoom_ = scaleAtTouch_ * (touchx_[1] - touchx_[0]);
         // TODO: min and max zoom values maybe should depend on screen size
+        // Also, zoom range should be on the larger side for 3 level layout
         zoom_ = Math.max(1.0f, zoom_);
-        zoom_ = Math.min(4.0f, zoom_);
+        zoom_ = Math.min(5.0f, zoom_);
         offset_ = touchx_[0] + zoom_ / zoomAtTouch_ * deltaAtTouch_;
         redraw = true;
       }