Working physical keyboard mapping

app/src/main/java/cfpi_fpsi/eu/titanboard/TitanboardIME.java

@@ -1,28 +1,77 @@
 package cfpi_fpsi.eu.titanboard;
 
 import android.inputmethodservice.InputMethodService;
-import android.view.KeyCharacterMap;
+import android.util.Log;
 import android.view.KeyEvent;
 import android.view.View;
 import android.view.inputmethod.EditorInfo;
 import android.view.inputmethod.InputConnection;
 
+import org.xmlpull.v1.XmlPullParser;
+import org.xmlpull.v1.XmlPullParserException;
+
+import java.io.IOException;
+import java.util.HashMap;
+
 public class TitanboardIME extends InputMethodService {
+    private HashMap<Integer, int[]> keymap;
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+
+        keymap = new HashMap<>();
+        // We load the keymap from the XML file into a variable
+        XmlPullParser parser = getResources().getXml(getResources()
+                .getIdentifier("keymap_titan", "xml", getPackageName()));
+        int code = 0;
+        int value = 0;
+        int alt = 0;
+        try {
+            while (parser.getEventType() != XmlPullParser.END_DOCUMENT) {
+                switch (parser.getEventType()) {
+                    case XmlPullParser.START_TAG:
+                        if (parser.getName().equals("key")) {
+                            for (int i = 0; i < parser.getAttributeCount(); ++i) {
+                                switch (parser.getAttributeName(i)) {
+                                    case "code":
+                                        code = Integer.parseInt(parser.getAttributeValue(i));
+                                        Log.d("STATE", "KeyCode: " + code);
+                                        break;
+                                    case "value":
+                                        value = Integer.parseInt(String.valueOf(parser.getAttributeValue(i).codePointAt(0)));
+                                        break;
+                                    case "alt":
+                                        alt = Integer.parseInt(String.valueOf(parser.getAttributeValue(i).codePointAt(0)));
+                                        break;
+                                }
+                            }
+                        }
+                        break;
+                    case XmlPullParser.END_TAG:
+                        if (parser.getName().equals("key")) {
+                            Log.d("STATE", "Adding KeyCode " + code + " which corresponds to: " + value + " and " + alt);
+                            keymap.put(code, new int[] { value, alt });
+                        }
+                        break;
+                    default:
+                        break;
+                }
+
+                parser.next();
+            }
+        } catch (XmlPullParserException e) {
+            throw new RuntimeException(e);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
     @Override
     public View onCreateInputView() {
         return getLayoutInflater().inflate(R.layout.input, null);
     }
 
-    @Override
-    public View onCreateCandidatesView() {
-        return null;
-    }
-
-    @Override
-    public boolean onKeyUp(int keyCode, KeyEvent event) {
-        return super.onKeyUp(keyCode, event);
-    }
-
     @Override
     public boolean onKeyDown(int keyCode, KeyEvent event) {
         InputConnection conn = getCurrentInputConnection();
@@ -47,12 +96,25 @@ public class TitanboardIME extends InputMethodService {
             case KeyEvent.KEYCODE_DEL:
                 conn.deleteSurroundingText(1, 0);
                 return true;
-            default:
-                // We get the current key mapping.
-                KeyCharacterMap map = event.getKeyCharacterMap();
-                // And we send the character to the app.
-                conn.commitText(new String(Character.toChars(map.get(keyCode, event.getMetaState()))), 1);
+                // We suppress the alt keys so the system cannot use them.
+            case KeyEvent.KEYCODE_ALT_LEFT:
+            case KeyEvent.KEYCODE_ALT_RIGHT:
                 return true;
+            default:
+                // And we send the character to the app.
+                int[] key = keymap.get(keyCode);
+                if (key != null) {
+                    if (event.isAltPressed()) {
+                        conn.commitText(new String(Character.toChars(key[1])), 1);
+                    } else if (event.isShiftPressed()) {
+                        conn.commitText(new String(Character.toChars(key[0])).toUpperCase(), 1);
+                    } else {
+                        conn.commitText(new String(Character.toChars(key[0])), 1);
+                    }
+                    return true;
+                } else {
+                    return false;
+                }
         }
     }
 }

app/src/main/res/xml/keymap_titan.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<keymap>
+    <key code="29" value="a" alt="@"/>
+    <key code="30" value="b" alt="7"/>
+    <key code="31" value="c" alt=","/>
+    <key code="32" value="d" alt="&quot;"/>
+    <key code="33" value="e" alt="_"/>
+    <key code="34" value="f" alt="+"/>
+    <key code="35" value="g" alt="*"/>
+    <key code="36" value="h" alt="#"/>
+    <key code="37" value="i" alt="2"/>
+    <key code="38" value="j" alt="4"/>
+    <key code="39" value="k" alt="5"/>
+    <key code="40" value="l" alt="6"/>
+    <key code="41" value="m" alt="9"/>
+    <key code="42" value="n" alt="8"/>
+    <key code="43" value="o" alt="3"/>
+    <key code="44" value="p" alt="0"/>
+    <key code="45" value="q" alt=":"/>
+    <key code="46" value="r" alt="-"/>
+    <key code="47" value="s" alt="&apos;"/>
+    <key code="48" value="t" alt="("/>
+    <key code="49" value="u" alt="1"/>
+    <key code="50" value="v" alt="."/>
+    <key code="51" value="w" alt="/"/>
+    <key code="52" value="x" alt="?"/>
+    <key code="53" value="y" alt=")"/>
+    <key code="54" value="z" alt="!"/>
+</keymap>