Merge "Make the Builder fully immutable at last"
diff --git a/java/res/values-fa/donottranslate-more-keys.xml b/java/res/values-fa/donottranslate-more-keys.xml
new file mode 100644
index 0000000..3e13c79
--- /dev/null
+++ b/java/res/values-fa/donottranslate-more-keys.xml
@@ -0,0 +1,160 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+**
+** Copyright 2012, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+**     http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+-->
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+    <!-- U+061F: "؟" ARABIC QUESTION MARK
+         U+060C: "،" ARABIC COMMA
+         U+061B: "؛" ARABIC SEMICOLON -->
+    <!-- U+0650: "ِ" ARABIC KASRA
+         U+064E: "َ" ARABIC FATHA
+         U+064D: "ٍ" ARABIC KASRATAN
+         U+064B: "ً" ARABIC FATHATAN
+         U+0656: "ٖ" ARABIC SUBSCRIPT ALEF
+         U+0670: "ٰ" ARABIC LETTER SUPERSCRIPT ALEF
+         U+0655: "ٕ" ARABIC HAMZA BELOW
+         U+0654: "ٔ" ARABIC HAMZA ABOVE -->
+    <!-- U+064F: "ُ" ARABIC DAMMA
+         U+064C: "ٌ" ARABIC DAMMATAN
+         U+0651: "ّ" ARABIC SHADDA
+         U+0652: "ْ" ARABIC SUKUN
+         U+0653: "ٓ" ARABIC MADDAH ABOVE
+         U+0640: "ـ" ARABIC TATWEEL -->
+    <!-- In order to make Tatweel easily distinguishable from other punctuations, we use consecutive Tatweels only for its displayed label. -->
+    <string name="more_keys_for_punctuation">"!fixedColumnOrder!8,\",\',-,:,!,&#x061F;,&#x060C;,&#x061B;,&#x0650;,&#x064E;,&#x064D;,&#x064B;,&#x0656;,&#x0670;,&#x0655;,&#x0654;,&#x064F;,&#x064C;,&#x0651;,&#x0652;,&#x0653;,&#x0640;&#x0640;&#x0640;|&#x0640;,/"</string>
+    <string name="keyhintlabel_for_punctuation">&#x064B;</string>
+    <!-- U+0661: "١" ARABIC-INDIC DIGIT ONE -->
+    <string name="keylabel_for_symbols_1">&#x0661;</string>
+    <!-- U+0662: "٢" ARABIC-INDIC DIGIT TWO -->
+    <string name="keylabel_for_symbols_2">&#x0662;</string>
+    <!-- U+0663: "٣" ARABIC-INDIC DIGIT THREE -->
+    <string name="keylabel_for_symbols_3">&#x0663;</string>
+    <!-- U+0664: "٤" ARABIC-INDIC DIGIT FOUR -->
+    <string name="keylabel_for_symbols_4">&#x0664;</string>
+    <!-- U+0665: "٥" ARABIC-INDIC DIGIT FIVE -->
+    <string name="keylabel_for_symbols_5">&#x0665;</string>
+    <!-- U+0666: "٦" ARABIC-INDIC DIGIT SIX -->
+    <string name="keylabel_for_symbols_6">&#x0666;</string>
+    <!-- U+0667: "٧" ARABIC-INDIC DIGIT SEVEN -->
+    <string name="keylabel_for_symbols_7">&#x0667;</string>
+    <!-- U+0668: "٨" ARABIC-INDIC DIGIT EIGHT -->
+    <string name="keylabel_for_symbols_8">&#x0668;</string>
+    <!-- U+0669: "٩" ARABIC-INDIC DIGIT NINE -->
+    <string name="keylabel_for_symbols_9">&#x0669;</string>
+    <!-- U+0660: "٠" ARABIC-INDIC DIGIT ZERO -->
+    <string name="keylabel_for_symbols_0">&#x0660;</string>
+    <string name="additional_more_keys_for_symbols_1">1</string>
+    <string name="additional_more_keys_for_symbols_2">2</string>
+    <string name="additional_more_keys_for_symbols_3">3</string>
+    <string name="additional_more_keys_for_symbols_4">4</string>
+    <string name="additional_more_keys_for_symbols_5">5</string>
+    <string name="additional_more_keys_for_symbols_6">6</string>
+    <string name="additional_more_keys_for_symbols_7">7</string>
+    <string name="additional_more_keys_for_symbols_8">8</string>
+    <string name="additional_more_keys_for_symbols_9">9</string>
+    <!-- U+066B: "٫" ARABIC DECIMAL SEPARATOR
+         U+066C: "٬" ARABIC THOUSANDS SEPARATOR -->
+    <string name="additional_more_keys_for_symbols_0">0,&#x066B;,&#x066C;</string>
+    <!-- U+060C: "،" ARABIC COMMA -->
+    <string name="keylabel_for_comma">&#x060C;</string>
+    <string name="more_keys_for_comma">"\\,"</string>
+    <string name="keylabel_for_symbols_question">&#x061F;</string>
+    <string name="keylabel_for_symbols_semicolon">&#x061B;</string>
+    <!-- U+066A: "٪" ARABIC PERCENT SIGN -->
+    <string name="keylabel_for_symbols_percent">&#x066A;</string>
+    <string name="more_keys_for_symbols_question">\?</string>
+    <string name="more_keys_for_symbols_semicolon">;</string>
+    <!-- U+2030: "‰" PER MILLE SIGN -->
+    <string name="more_keys_for_symbols_percent">%,&#x2030;</string>
+    <!-- U+060C: "،" ARABIC COMMA
+         U+061B: "؛" ARABIC SEMICOLON
+         U+061F: "؟" ARABIC QUESTION MARK -->
+    <string name="keylabel_for_apostrophe">&#x060C;</string>
+    <string name="keylabel_for_dash">"."</string>
+    <string name="keyhintlabel_for_apostrophe">&#x061F;</string>
+    <string name="keyhintlabel_for_dash">&#x064B;</string>
+    <string name="more_keys_for_apostrophe">"&#x061F;,&#x061B;,!,:,-,/,\',\""</string>
+    <!-- U+0651: "ّ" ARABIC SHADDA
+         U+0652: "ْ" ARABIC SUKUN
+         U+064C: "ٌ" ARABIC DAMMATAN
+         U+0653: "ٓ" ARABIC MADDAH ABOVE
+         U+064F: "ُ" ARABIC DAMMA -->
+    <!-- U+0650: "ِ" ARABIC KASRA
+         U+064E: "َ" ARABIC FATHA
+         U+064B: "ً" ARABIC FATHATAN
+         U+0640: "ـ" ARABIC TATWEEL
+         U+064D: "ٍ" ARABIC KASRATAN -->
+    <!-- U+0670: "ٰ" ARABIC LETTER SUPERSCRIPT ALEF
+         U+0656: "ٖ" ARABIC SUBSCRIPT ALEF
+         U+0654: "ٔ" ARABIC HAMZA ABOVE
+         U+0655: "ٕ" ARABIC HAMZA BELOW -->
+    <!-- In order to make Tatweel easily distinguishable from other punctuations, we use consecutive Tatweels only for its displayed label. -->
+    <string name="more_keys_for_dash">"&#x0651;,&#x0652;,&#x064C;,&#x0653;,&#x064F;,&#x0650;,&#x064E;,&#x064B;,&#x0640;&#x0640;&#x0640;|&#x0640;,&#x064D;,&#x0654;,&#x0656;,&#x0655;,&#x0670;"</string>
+    <!-- U+266A: "♪" EIGHTH NOTE -->
+    <string name="more_keys_for_bullet">&#x266A;</string>
+    <!-- U+2605: "★" BLACK STAR
+         U+066D: "٭" ARABIC FIVE POINTED STAR -->
+    <string name="more_keys_for_star">&#x2605;,&#x066D;</string>
+    <!-- The all letters need to be mirrored are found at
+         http://www.unicode.org/Public/6.1.0/ucd/BidiMirroring.txt -->
+    <!-- U+0029: ")" RIGHT PARENTHESIS -->
+    <integer name="keycode_for_left_parenthesis">0x0029</integer>
+    <!-- U+0028: "(" LEFT PARENTHESIS -->
+    <integer name="keycode_for_right_parenthesis">0x0028</integer>
+    <!-- U+FD3E: "﴾" ORNATE LEFT PARENTHESIS
+         U+FD3F: "﴿" ORNATE RIGHT PARENTHESIS -->
+    <!-- TODO: DroidSansArabic lacks the glyph of U+FD3E ORNATE LEFT PARENTHESIS -->
+    <!-- TODO: DroidSansArabic lacks the glyph of U+FD3F ORNATE RIGHT PARENTHESIS -->
+    <string name="more_keys_for_left_parenthesis">!fixedColumnOrder!4,&#xFD3E;|&#xFD3F;,&lt;|&gt;,{|},[|]</string>
+    <string name="more_keys_for_right_parenthesis">!fixedColumnOrder!4,&#xFD3F;|&#xFD3E;,&gt;|&lt;,}|{,]|[</string>
+    <!-- U+003E: ">" GREATER-THAN SIGN -->
+    <integer name="keycode_for_less_than">0x003E</integer>
+    <!-- U+003C: "<" LESS-THAN SIGN -->
+    <integer name="keycode_for_greater_than">0x003C</integer>
+    <!-- U+2264: "≤" LESS-THAN OR EQUAL TO
+         U+2265: "≥" GREATER-THAN EQUAL TO
+         U+00AB: "«" LEFT-POINTING DOUBLE ANGLE QUOTATION MARK
+         U+00BB: "»" RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK
+         U+2039: "‹" SINGLE LEFT-POINTING ANGLE QUOTATION MARK
+         U+203A: "›" SINGLE RIGHT-POINTING ANGLE QUOTATION MARK
+         The following characters don't need BIDI mirroring.
+         U+2018: "‘" LEFT SINGLE QUOTATION MARK
+         U+2019: "’" RIGHT SINGLE QUOTATION MARK
+         U+201A: "‚" SINGLE LOW-9 QUOTATION MARK
+         U+201B: "‛" SINGLE HIGH-REVERSED-9 QUOTATION MARK
+         U+201C: "“" LEFT DOUBLE QUOTATION MARK
+         U+201D: "”" RIGHT DOUBLE QUOTATION MARK
+         U+201E: "„" DOUBLE LOW-9 QUOTATION MARK
+         U+201F: "‟" DOUBLE HIGH-REVERSED-9 QUOTATION MARK -->
+    <string name="more_keys_for_less_than">!fixedColumnOrder!3,&#x2039;|&#x203A;,&#x2264;|&#x2265;,&#x00AB;|&#x00BB;</string>
+    <string name="more_keys_for_greater_than">!fixedColumnOrder!3,&#x203A;|&#x2039;,&#x2265;|&#x2264;,&#x00BB;|&#x00AB;</string>
+    <!-- U+005D: "]" RIGHT SQUARE BRACKET -->
+    <integer name="keycode_for_left_square_bracket">0x005D</integer>
+    <!-- U+005B: "[" LEFT SQUARE BRACKET -->
+    <integer name="keycode_for_right_square_bracket">0x005B</integer>
+    <!-- U+007D: "}" RIGHT CURLY BRACKET -->
+    <integer name="keycode_for_left_curly_bracket">0x007D</integer>
+    <!-- U+007B: "{" LEFT CURLY BRACKET -->
+    <integer name="keycode_for_right_curly_bracket">0x007B</integer>
+    <!-- TODO: Neither DroidSans nor Roboto have the glyph for U+201F DOUBLE HIGH-REVERSED-9 QUOTATION MARK -->
+    <!-- <string name="more_keys_for_double_quote">&#x201C;,&#x201D;,&#x201E;,&#x201F;,&#x00AB;|&#x00BB;,&#x00BB;|&#x00AB;</string> -->
+    <string name="more_keys_for_double_quote">!fixedColumnOrder!4,&#x201C;,&#x201D;,&#x00AB;|&#x00BB;,&#x00BB;|&#x00AB;</string>
+    <!-- TODO: Neither DroidSans nor Roboto have the glyph for U+201F DOUBLE HIGH-REVERSED-9 QUOTATION MARK -->
+    <!-- <string name="more_keys_for_tablet_double_quote">!fixedColumnOrder!6,&#x201C;,&#x201D;,&#x201E;,&#x201F;,&#x00AB;|&#x00BB;,&#x00BB|&#x00AB;;,&#x2018;,&#x2019;,&#x201A;,&#x201B;</string> -->
+    <string name="more_keys_for_tablet_double_quote">!fixedColumnOrder!4,&#x201C;,&#x201D;,&#x00AB;|&#x00BB;,&#x00BB;|&#x00AB;,&#x2018;,&#x2019;,&#x201A;,&#x201B;</string>
+</resources>
diff --git a/java/res/values-fa/donottranslate.xml b/java/res/values-fa/donottranslate.xml
new file mode 100644
index 0000000..57de253
--- /dev/null
+++ b/java/res/values-fa/donottranslate.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+**
+** Copyright 2012, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+**     http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+-->
+<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+    <!-- The all letters need to be mirrored are found at
+         http://www.unicode.org/Public/6.1.0/ucd/BidiMirroring.txt -->
+    <!-- Symbols that are suggested between words -->
+    <string name="suggested_punctuations">!,?,\\,,:,;,\",(|),)|(,\',-,/,@,_</string>
+</resources>
diff --git a/java/res/values-in/strings.xml b/java/res/values-in/strings.xml
index 1f03a05..f10d613 100644
--- a/java/res/values-in/strings.xml
+++ b/java/res/values-in/strings.xml
@@ -45,7 +45,7 @@
     <skip />
     <string name="key_preview_popup_dismiss_delay" msgid="6213164897443068248">"Tundaan singkir munculan kunci"</string>
     <string name="key_preview_popup_dismiss_no_delay" msgid="2096123151571458064">"Tanpa penundaan"</string>
-    <string name="key_preview_popup_dismiss_default_delay" msgid="2166964333903906734">"Bawaan"</string>
+    <string name="key_preview_popup_dismiss_default_delay" msgid="2166964333903906734">"Default"</string>
     <string name="use_contacts_dict" msgid="4435317977804180815">"Sarankan nama Kenalan"</string>
     <string name="use_contacts_dict_summary" msgid="6599983334507879959">"Menggunakan nama dari Kenalan untuk saran dan koreksi"</string>
     <string name="enable_span_insert" msgid="7204653105667167620">"Aktifkan koreksi ulang"</string>
diff --git a/java/res/xml-fa/keyboard_set.xml b/java/res/xml-fa/keyboard_set.xml
new file mode 100644
index 0000000..9bd1050
--- /dev/null
+++ b/java/res/xml-fa/keyboard_set.xml
@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+**
+** Copyright 2012, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+**     http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+*/
+-->
+
+<KeyboardSet
+    xmlns:latin="http://schemas.android.com/apk/res/com.android.inputmethod.latin"
+    latin:keyboardLocale="fa" >
+    <Element
+        latin:elementName="alphabet"
+        latin:elementKeyboard="@xml/kbd_arabic" />
+    <Element
+        latin:elementName="symbols"
+        latin:elementKeyboard="@xml/kbd_symbols" />
+    <Element
+        latin:elementName="symbolsShifted"
+        latin:elementKeyboard="@xml/kbd_symbols_shift" />
+    <Element
+        latin:elementName="phone"
+        latin:elementKeyboard="@xml/kbd_phone" />
+    <Element
+        latin:elementName="phoneSymbols"
+        latin:elementKeyboard="@xml/kbd_phone_symbols" />
+    <Element
+        latin:elementName="number"
+        latin:elementKeyboard="@xml/kbd_number" />
+</KeyboardSet>
diff --git a/java/res/xml-sw600dp/key_styles_common.xml b/java/res/xml-sw600dp/key_styles_common.xml
index 2fa8b38..b206f0e 100644
--- a/java/res/xml-sw600dp/key_styles_common.xml
+++ b/java/res/xml-sw600dp/key_styles_common.xml
@@ -79,9 +79,12 @@
         latin:code="@integer/key_space"
         latin:keyActionFlags="noKeyPreview" />
     <key-style
-        latin:styleName="nonSpecialBackgroundSpaceKeyStyle"
-        latin:code="@integer/key_space"
-        latin:keyActionFlags="noKeyPreview" />
+        latin:styleName="zwnjKeyStyle"
+        latin:keyLabel="&#x200C;"
+        latin:moreKeys="&#x200D;"
+        latin:keyLabelFlags="hasPopupHint"
+        latin:altCode="@integer/key_space"
+        latin:keyActionFlags="altCodeWhileTyping" />
     <key-style
         latin:styleName="smileyKeyStyle"
         latin:keyLabel=":-)"
diff --git a/java/res/xml-sw600dp/row_qwerty4.xml b/java/res/xml-sw600dp/row_qwerty4.xml
index 3c2f06d..eec35b0 100644
--- a/java/res/xml-sw600dp/row_qwerty4.xml
+++ b/java/res/xml-sw600dp/row_qwerty4.xml
@@ -50,10 +50,24 @@
                     latin:keyStyle="hasShiftedLetterHintStyle" />
             </default>
         </switch>
-        <Key
-            latin:keyStyle="spaceKeyStyle"
-            latin:keyXPos="30.750%p"
-            latin:keyWidth="39.750%p" />
+        <switch>
+            <case
+                latin:languageCode="fa"
+            >
+                <Key
+                    latin:keyStyle="spaceKeyStyle"
+                    latin:keyXPos="30.750%p"
+                    latin:keyWidth="30.850%p" />
+                <Key
+                    latin:keyStyle="zwnjKeyStyle" />
+            </case>
+            <default>
+                <Key
+                    latin:keyStyle="spaceKeyStyle"
+                    latin:keyXPos="30.750%p"
+                    latin:keyWidth="39.750%p" />
+            </default>
+        </switch>
         <switch>
             <case
                 latin:languageCode="iw"
diff --git a/java/res/xml-sw600dp/rows_number_normal.xml b/java/res/xml-sw600dp/rows_number_normal.xml
index 3704c52..be5776b 100644
--- a/java/res/xml-sw600dp/rows_number_normal.xml
+++ b/java/res/xml-sw600dp/rows_number_normal.xml
@@ -143,7 +143,7 @@
             latin:keyStyle="numTabKeyStyle"
             latin:keyWidth="11.00%p" />
         <Key
-            latin:keyStyle="nonSpecialBackgroundSpaceKeyStyle"
+            latin:keyStyle="spaceKeyStyle"
             latin:keyWidth="27.75%p"
             latin:keyXPos="12.75%p" />
         <Key
diff --git a/java/res/xml-sw600dp/rows_phone.xml b/java/res/xml-sw600dp/rows_phone.xml
index 4c896e9..e892693 100644
--- a/java/res/xml-sw600dp/rows_phone.xml
+++ b/java/res/xml-sw600dp/rows_phone.xml
@@ -112,7 +112,7 @@
             latin:keyStyle="numTabKeyStyle"
             latin:keyWidth="11.00%p" />
         <Key
-            latin:keyStyle="nonSpecialBackgroundSpaceKeyStyle"
+            latin:keyStyle="spaceKeyStyle"
             latin:keyWidth="27.75%p"
             latin:keyXPos="12.75%p" />
         <Key
diff --git a/java/res/xml-sw768dp/key_styles_common.xml b/java/res/xml-sw768dp/key_styles_common.xml
index 5c35f1c..069fc63 100644
--- a/java/res/xml-sw768dp/key_styles_common.xml
+++ b/java/res/xml-sw768dp/key_styles_common.xml
@@ -78,9 +78,12 @@
         latin:code="@integer/key_space"
         latin:keyActionFlags="noKeyPreview" />
     <key-style
-        latin:styleName="nonSpecialBackgroundSpaceKeyStyle"
-        latin:code="@integer/key_space"
-        latin:keyActionFlags="noKeyPreview" />
+        latin:styleName="zwnjKeyStyle"
+        latin:keyLabel="&#x200C;"
+        latin:moreKeys="&#x200D;"
+        latin:keyLabelFlags="hasPopupHint"
+        latin:altCode="@integer/key_space"
+        latin:keyActionFlags="altCodeWhileTyping" />
     <key-style
         latin:styleName="smileyKeyStyle"
         latin:keyLabel=":-)"
diff --git a/java/res/xml-sw768dp/row_qwerty4.xml b/java/res/xml-sw768dp/row_qwerty4.xml
index 24c081e..0aa04f8 100644
--- a/java/res/xml-sw768dp/row_qwerty4.xml
+++ b/java/res/xml-sw768dp/row_qwerty4.xml
@@ -76,10 +76,30 @@
                 </switch>
             </default>
         </switch>
-        <Key
-            latin:keyStyle="spaceKeyStyle"
-            latin:keyXPos="31.250%p"
-            latin:keyWidth="37.500%p" />
+        <switch>
+            <case
+                latin:languageCode="fa"
+            >
+                <Key
+                    latin:keyStyle="spaceKeyStyle"
+                    latin:keyXPos="31.250%p"
+                    latin:keyWidth="29.453%p" />
+                <!-- U+200C: "" ZERO WIDTH NON-JOINER
+                     U+200D: "" ZERO WIDTH JOINER -->
+                <Key
+                    latin:keyLabel="&#x200C;"
+                    latin:moreKeys="&#x200D;"
+                    latin:keyLabelFlags="hasPopupHint"
+                    latin:altCode="@integer/key_space"
+                    latin:keyActionFlags="altCodeWhileTyping" />
+            </case>
+            <default>
+                <Key
+                    latin:keyStyle="spaceKeyStyle"
+                    latin:keyXPos="31.250%p"
+                    latin:keyWidth="37.500%p" />
+            </default>
+        </switch>
         <switch>
             <case
                 latin:languageCode="iw"
diff --git a/java/res/xml-sw768dp/rows_number_normal.xml b/java/res/xml-sw768dp/rows_number_normal.xml
index 8bf1a17..2eeb6c9 100644
--- a/java/res/xml-sw768dp/rows_number_normal.xml
+++ b/java/res/xml-sw768dp/rows_number_normal.xml
@@ -145,7 +145,7 @@
             latin:keyboardLayout="@xml/key_settings"
             latin:keyWidth="8.047%p" />
         <Key
-            latin:keyStyle="nonSpecialBackgroundSpaceKeyStyle"
+            latin:keyStyle="spaceKeyStyle"
             latin:keyXPos="13.829%p"
             latin:keyWidth="24.140%p" />
         <Key
diff --git a/java/res/xml-sw768dp/rows_phone.xml b/java/res/xml-sw768dp/rows_phone.xml
index 69c9e86..216fbed 100644
--- a/java/res/xml-sw768dp/rows_phone.xml
+++ b/java/res/xml-sw768dp/rows_phone.xml
@@ -114,7 +114,7 @@
             latin:keyboardLayout="@xml/key_settings"
             latin:keyWidth="8.047%p" />
         <Key
-            latin:keyStyle="nonSpecialBackgroundSpaceKeyStyle"
+            latin:keyStyle="spaceKeyStyle"
             latin:keyXPos="13.829%p"
             latin:keyWidth="24.140%p" />
         <Key
diff --git a/java/res/xml/key_styles_common.xml b/java/res/xml/key_styles_common.xml
index f153a7d..7b526c0 100644
--- a/java/res/xml/key_styles_common.xml
+++ b/java/res/xml/key_styles_common.xml
@@ -108,6 +108,14 @@
         latin:keyActionFlags="noKeyPreview|enableLongPress"
         latin:backgroundType="functional" />
     <key-style
+        latin:styleName="zwnjKeyStyle"
+        latin:keyLabel="&#x200C;"
+        latin:moreKeys="&#x200D;"
+        latin:keyLabelFlags="hasPopupHint"
+        latin:altCode="@integer/key_space"
+        latin:keyActionFlags="altCodeWhileTyping"
+        latin:backgroundType="functional" />
+    <key-style
         latin:styleName="shortcutKeyStyle"
         latin:code="@integer/key_shortcut"
         latin:keyIcon="iconShortcutKey"
@@ -123,6 +131,8 @@
         latin:keyActionFlags="noKeyPreview|altCodeWhileTyping|enableLongPress"
         latin:altCode="@integer/key_space"
         latin:backgroundType="functional" />
+    <!-- U+200C: "" ZERO WIDTH NON-JOINER
+         U+200D: "" ZERO WIDTH JOINER -->
     <key-style
         latin:styleName="tabKeyStyle"
         latin:code="@integer/key_tab"
diff --git a/java/res/xml/method.xml b/java/res/xml/method.xml
index f330b26..cdcea0e 100644
--- a/java/res/xml/method.xml
+++ b/java/res/xml/method.xml
@@ -33,6 +33,7 @@
     en_GB: English Great Britain/qwerty
     es: Spanish/spanish
     et: Estonian/nordic
+    fa: Persian/arabic
     fi: Finnish/nordic
     fr: French/azerty
     fr_CA: French Canada/qwerty
@@ -140,6 +141,12 @@
     />
     <subtype android:icon="@drawable/ic_subtype_keyboard"
             android:label="@string/subtype_generic"
+            android:imeSubtypeLocale="fa"
+            android:imeSubtypeMode="keyboard"
+            android:imeSubtypeExtraValue="SupportTouchPositionCorrection"
+    />
+    <subtype android:icon="@drawable/ic_subtype_keyboard"
+            android:label="@string/subtype_generic"
             android:imeSubtypeLocale="fi"
             android:imeSubtypeMode="keyboard"
             android:imeSubtypeExtraValue="AsciiCapable,SupportTouchPositionCorrection"
diff --git a/java/res/xml/row_qwerty4.xml b/java/res/xml/row_qwerty4.xml
index 0dd2177..b2b47e9 100644
--- a/java/res/xml/row_qwerty4.xml
+++ b/java/res/xml/row_qwerty4.xml
@@ -59,6 +59,28 @@
         </switch>
         <switch>
             <case
+                latin:languageCode="fa"
+                latin:languageSwitchKeyEnabled="true"
+            >
+                <Key
+                    latin:keyStyle="languageSwitchKeyStyle" />
+                <Key
+                    latin:keyStyle="spaceKeyStyle"
+                    latin:keyWidth="30%p" />
+                <Key
+                    latin:keyStyle="zwnjKeyStyle" />
+            </case>
+            <case
+                latin:languageCode="fa"
+                latin:languageSwitchKeyEnabled="false"
+            >
+                <Key
+                    latin:keyStyle="spaceKeyStyle"
+                    latin:keyWidth="40%p" />
+                <Key
+                    latin:keyStyle="zwnjKeyStyle" />
+            </case>
+            <case
                 latin:languageSwitchKeyEnabled="true"
             >
                 <Key
diff --git a/java/src/com/android/inputmethod/accessibility/AccessibilityEntityProvider.java b/java/src/com/android/inputmethod/accessibility/AccessibilityEntityProvider.java
index dc7c12b..dd43166 100644
--- a/java/src/com/android/inputmethod/accessibility/AccessibilityEntityProvider.java
+++ b/java/src/com/android/inputmethod/accessibility/AccessibilityEntityProvider.java
@@ -36,7 +36,6 @@
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
-import java.util.Set;
 
 /**
  * Exposes a virtual view sub-tree for {@link KeyboardView} and generates
@@ -135,9 +134,9 @@
             ViewCompat.onInitializeAccessibilityNodeInfo(mKeyboardView, info);
 
             // Add the virtual children of the root View.
-            // TODO(alanv): Need to assign a unique ID to each key.
+            // TODO: Need to assign a unique ID to each key.
             final Keyboard keyboard = mKeyboardView.getKeyboard();
-            final Set<Key> keys = keyboard.mKeys;
+            final Key[] keys = keyboard.mKeys;
             for (Key key : keys) {
                 final int childVirtualViewId = generateVirtualViewIdForKey(key);
                 info.addChild(mKeyboardView, childVirtualViewId);
@@ -342,8 +341,8 @@
 
         mVirtualViewIdToKey.clear();
 
-        final Set<Key> keySet = keyboard.mKeys;
-        for (Key key : keySet) {
+        final Key[] keys = keyboard.mKeys;
+        for (Key key : keys) {
             final int virtualViewId = generateVirtualViewIdForKey(key);
             mVirtualViewIdToKey.put(virtualViewId, key);
         }
diff --git a/java/src/com/android/inputmethod/compat/MotionEventCompatUtils.java b/java/src/com/android/inputmethod/compat/MotionEventCompatUtils.java
index eca922e..9a52301 100644
--- a/java/src/com/android/inputmethod/compat/MotionEventCompatUtils.java
+++ b/java/src/com/android/inputmethod/compat/MotionEventCompatUtils.java
@@ -17,7 +17,7 @@
 package com.android.inputmethod.compat;
 
 public class MotionEventCompatUtils {
-    // TODO(alanv): Remove after these are added to MotionEventCompat.
+    // TODO: Remove after these are added to MotionEventCompat.
     public static final int ACTION_HOVER_ENTER = 0x9;
     public static final int ACTION_HOVER_EXIT = 0xA;
 }
diff --git a/java/src/com/android/inputmethod/keyboard/Keyboard.java b/java/src/com/android/inputmethod/keyboard/Keyboard.java
index b7f1ddd..44c6a49 100644
--- a/java/src/com/android/inputmethod/keyboard/Keyboard.java
+++ b/java/src/com/android/inputmethod/keyboard/Keyboard.java
@@ -40,12 +40,9 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 /**
  * Loads an XML description of a keyboard and stores the attributes of the keys. A keyboard
@@ -125,16 +122,17 @@
     /** Maximum column for more keys keyboard */
     public final int mMaxMoreKeysKeyboardColumn;
 
-    /** List of keys and icons in this keyboard */
-    public final Set<Key> mKeys;
-    public final Set<Key> mShiftKeys;
+    /** Array of keys and icons in this keyboard */
+    public final Key[] mKeys;
+    public final Key[] mShiftKeys;
+    public final Key[] mAltCodeKeysWhileTyping;
     public final KeyboardIconsSet mIconsSet;
 
-    private final Map<Integer, Key> mKeyCache = new HashMap<Integer, Key>();
+    private final HashMap<Integer, Key> mKeyCache = new HashMap<Integer, Key>();
 
     private final ProximityInfo mProximityInfo;
 
-    public final Map<Integer, List<Integer>> mAdditionalProximityChars;
+    private final Map<Integer, List<Integer>> mAdditionalProximityChars;
 
     public Keyboard(Params params) {
         mId = params.mId;
@@ -149,8 +147,10 @@
         mTopPadding = params.mTopPadding;
         mVerticalGap = params.mVerticalGap;
 
-        mKeys = Collections.unmodifiableSet(params.mKeys);
-        mShiftKeys = Collections.unmodifiableSet(params.mShiftKeys);
+        mKeys = params.mKeys.toArray(new Key[params.mKeys.size()]);
+        mShiftKeys = params.mShiftKeys.toArray(new Key[params.mShiftKeys.size()]);
+        mAltCodeKeysWhileTyping = params.mAltCodeKeysWhileTyping.toArray(
+                new Key[params.mAltCodeKeysWhileTyping.size()]);
         mIconsSet = params.mIconsSet;
         mAdditionalProximityChars = params.mAdditionalProximityChars;
 
@@ -225,8 +225,9 @@
         public int GRID_WIDTH;
         public int GRID_HEIGHT;
 
-        public final Set<Key> mKeys = new HashSet<Key>();
-        public final Set<Key> mShiftKeys = new HashSet<Key>();
+        public final ArrayList<Key> mKeys = new ArrayList<Key>();
+        public final ArrayList<Key> mShiftKeys = new ArrayList<Key>();
+        public final ArrayList<Key> mAltCodeKeysWhileTyping = new ArrayList<Key>();
         public final KeyboardIconsSet mIconsSet = new KeyboardIconsSet();
         // TODO: Should be in Key instead of Keyboard.Params?
         public final Map<Integer, List<Integer>> mAdditionalProximityChars =
@@ -308,12 +309,15 @@
             if (key.mCode == Keyboard.CODE_SHIFT) {
                 mShiftKeys.add(key);
             }
+            if (key.altCodeWhileTyping()) {
+                mAltCodeKeysWhileTyping.add(key);
+            }
         }
 
         private int mMaxHeightCount = 0;
         private int mMaxWidthCount = 0;
-        private final Map<Integer, Integer> mHeightHistogram = new HashMap<Integer, Integer>();
-        private final Map<Integer, Integer> mWidthHistogram = new HashMap<Integer, Integer>();
+        private final HashMap<Integer, Integer> mHeightHistogram = new HashMap<Integer, Integer>();
+        private final HashMap<Integer, Integer> mWidthHistogram = new HashMap<Integer, Integer>();
 
         private void clearHistogram() {
             mMostCommonKeyHeight = 0;
@@ -325,7 +329,8 @@
             mWidthHistogram.clear();
         }
 
-        private static int updateHistogramCounter(Map<Integer, Integer> histogram, Integer key) {
+        private static int updateHistogramCounter(HashMap<Integer, Integer> histogram,
+                Integer key) {
             final int count = (histogram.containsKey(key) ? histogram.get(key) : 0) + 1;
             histogram.put(key, count);
             return count;
diff --git a/java/src/com/android/inputmethod/keyboard/PointerTracker.java b/java/src/com/android/inputmethod/keyboard/PointerTracker.java
index 7a9915b..607b33b 100644
--- a/java/src/com/android/inputmethod/keyboard/PointerTracker.java
+++ b/java/src/com/android/inputmethod/keyboard/PointerTracker.java
@@ -25,8 +25,6 @@
 import com.android.inputmethod.latin.LatinImeLogger;
 
 import java.util.ArrayList;
-import java.util.List;
-import java.util.Set;
 
 public class PointerTracker {
     private static final String TAG = PointerTracker.class.getSimpleName();
@@ -109,7 +107,7 @@
     private static LatinKeyboardView.PointerTrackerParams sParams;
     private static int sTouchNoiseThresholdDistanceSquared;
 
-    private static final List<PointerTracker> sTrackers = new ArrayList<PointerTracker>();
+    private static final ArrayList<PointerTracker> sTrackers = new ArrayList<PointerTracker>();
     private static PointerTrackerQueue sPointerTrackerQueue;
 
     public final int mPointerId;
@@ -120,7 +118,6 @@
     private KeyboardActionListener mListener = EMPTY_LISTENER;
 
     private Keyboard mKeyboard;
-    private Set<Key> mKeys;
     private int mKeyQuarterWidthSquared;
     private final TextView mKeyPreviewText;
 
@@ -180,7 +177,7 @@
     }
 
     public static PointerTracker getPointerTracker(final int id, KeyEventHandler handler) {
-        final List<PointerTracker> trackers = sTrackers;
+        final ArrayList<PointerTracker> trackers = sTrackers;
 
         // Create pointer trackers until we can get 'id+1'-th tracker, if needed.
         for (int i = trackers.size(); i <= id; i++) {
@@ -303,7 +300,6 @@
     private void setKeyDetectorInner(KeyDetector keyDetector) {
         mKeyDetector = keyDetector;
         mKeyboard = keyDetector.getKeyboard();
-        mKeys = mKeyboard.mKeys;
         final int keyQuarterWidth = mKeyboard.mMostCommonKeyWidth / 4;
         mKeyQuarterWidthSquared = keyQuarterWidth * keyQuarterWidth;
     }
@@ -326,55 +322,74 @@
 
     private void setReleasedKeyGraphics(Key key) {
         mDrawingProxy.dismissKeyPreview(this);
-        if (key != null && key.isEnabled()) {
-            key.onReleased();
-            mDrawingProxy.invalidateKey(key);
+        if (key == null || !key.isEnabled()) {
+            return;
+        }
 
-            if (key.isShift()) {
-                for (final Key shiftKey : mKeyboard.mShiftKeys) {
-                    if (shiftKey != key) {
-                        shiftKey.onReleased();
-                        mDrawingProxy.invalidateKey(shiftKey);
-                    }
+        updateReleaseKeyGraphics(key);
+
+        if (key.isShift()) {
+            for (final Key shiftKey : mKeyboard.mShiftKeys) {
+                if (shiftKey != key) {
+                    updateReleaseKeyGraphics(shiftKey);
                 }
             }
+        }
 
-            if (key.altCodeWhileTyping()) {
-                final Key altKey = mKeyboard.getKey(key.mAltCode);
-                if (altKey != null) {
-                    altKey.onReleased();
-                    mDrawingProxy.invalidateKey(altKey);
+        if (key.altCodeWhileTyping()) {
+            final int altCode = key.mAltCode;
+            final Key altKey = mKeyboard.getKey(altCode);
+            if (altKey != null) {
+                updateReleaseKeyGraphics(altKey);
+            }
+            for (final Key k : mKeyboard.mAltCodeKeysWhileTyping) {
+                if (k != key && k.mAltCode == altCode) {
+                    updateReleaseKeyGraphics(k);
                 }
             }
         }
     }
 
     private void setPressedKeyGraphics(Key key) {
-        if (key != null && key.isEnabled()) {
-            if (!key.noKeyPreview()) {
-                mDrawingProxy.showKeyPreview(this);
-            }
-            key.onPressed();
-            mDrawingProxy.invalidateKey(key);
+        if (key == null || !key.isEnabled()) {
+            return;
+        }
 
-            if (key.isShift()) {
-                for (final Key shiftKey : mKeyboard.mShiftKeys) {
-                    if (shiftKey != key) {
-                        shiftKey.onPressed();
-                        mDrawingProxy.invalidateKey(shiftKey);
-                    }
-                }
-            }
+        if (!key.noKeyPreview()) {
+            mDrawingProxy.showKeyPreview(this);
+        }
+        updatePressKeyGraphics(key);
 
-            if (key.altCodeWhileTyping() && mTimerProxy.isTyping()) {
-                final Key altKey = mKeyboard.getKey(key.mAltCode);
-                if (altKey != null) {
-                    // TODO: Show altKey's preview.
-                    altKey.onPressed();
-                    mDrawingProxy.invalidateKey(altKey);
+        if (key.isShift()) {
+            for (final Key shiftKey : mKeyboard.mShiftKeys) {
+                if (shiftKey != key) {
+                    updatePressKeyGraphics(shiftKey);
                 }
             }
         }
+
+        if (key.altCodeWhileTyping() && mTimerProxy.isTyping()) {
+            final int altCode = key.mAltCode;
+            final Key altKey = mKeyboard.getKey(altCode);
+            if (altKey != null) {
+                updatePressKeyGraphics(altKey);
+            }
+            for (final Key k : mKeyboard.mAltCodeKeysWhileTyping) {
+                if (k != key && k.mAltCode == altCode) {
+                    updatePressKeyGraphics(k);
+                }
+            }
+        }
+    }
+
+    private void updateReleaseKeyGraphics(Key key) {
+        key.onReleased();
+        mDrawingProxy.invalidateKey(key);
+    }
+
+    private void updatePressKeyGraphics(Key key) {
+        key.onPressed();
+        mDrawingProxy.invalidateKey(key);
     }
 
     public int getLastX() {
@@ -691,7 +706,7 @@
     }
 
     private boolean isMajorEnoughMoveToBeOnNewKey(int x, int y, Key newKey) {
-        if (mKeys == null || mKeyDetector == null)
+        if (mKeyDetector == null)
             throw new NullPointerException("keyboard and/or key detector not set");
         Key curKey = mCurrentKey;
         if (newKey == curKey) {
diff --git a/java/src/com/android/inputmethod/keyboard/ProximityInfo.java b/java/src/com/android/inputmethod/keyboard/ProximityInfo.java
index 8a65a5f..e2a4830 100644
--- a/java/src/com/android/inputmethod/keyboard/ProximityInfo.java
+++ b/java/src/com/android/inputmethod/keyboard/ProximityInfo.java
@@ -28,7 +28,6 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 public class ProximityInfo {
     public static final int MAX_PROXIMITY_CHARS_SIZE = 16;
@@ -50,8 +49,8 @@
     private final String mLocaleStr;
 
     ProximityInfo(String localeStr, int gridWidth, int gridHeight, int minWidth, int height,
-            int mostCommonKeyWidth,
-            int mostCommonKeyHeight, Set<Key> keys, TouchPositionCorrection touchPositionCorrection,
+            int mostCommonKeyWidth, int mostCommonKeyHeight, final Key[] keys,
+            TouchPositionCorrection touchPositionCorrection,
             Map<Integer, List<Integer>> additionalProximityChars) {
         if (TextUtils.isEmpty(localeStr)) {
             mLocaleStr = "";
@@ -77,8 +76,8 @@
     }
 
     public static ProximityInfo createDummyProximityInfo() {
-        return new ProximityInfo("", 1, 1, 1, 1, 1, 1, Collections.<Key> emptySet(),
-                null, Collections.<Integer, List<Integer>> emptyMap());
+        return new ProximityInfo("", 1, 1, 1, 1, 1, 1, EMPTY_KEY_ARRAY, null,
+                Collections.<Integer, List<Integer>> emptyMap());
     }
 
     public static ProximityInfo createSpellCheckerProximityInfo(final int[] proximity) {
@@ -106,8 +105,7 @@
     private native void releaseProximityInfoNative(long nativeProximityInfo);
 
     private final void setProximityInfo(Key[][] gridNeighborKeys, int keyboardWidth,
-            int keyboardHeight, Set<Key> keys,
-            TouchPositionCorrection touchPositionCorrection) {
+            int keyboardHeight, final Key[] keys, TouchPositionCorrection touchPositionCorrection) {
         final int[] proximityCharsArray = new int[mGridSize * MAX_PROXIMITY_CHARS_SIZE];
         Arrays.fill(proximityCharsArray, KeyDetector.NOT_A_CODE);
         for (int i = 0; i < mGridSize; ++i) {
@@ -117,7 +115,7 @@
                         gridNeighborKeys[i][j].mCode;
             }
         }
-        final int keyCount = keys.size();
+        final int keyCount = keys.length;
         final int[] keyXCoordinates = new int[keyCount];
         final int[] keyYCoordinates = new int[keyCount];
         final int[] keyWidths = new int[keyCount];
@@ -132,8 +130,8 @@
             sweetSpotCenterYs = new float[keyCount];
             sweetSpotRadii = new float[keyCount];
             calculateSweetSpotParams = true;
-            int i = 0;
-            for (final Key key : keys) {
+            for (int i = 0; i < keyCount; i++) {
+                final Key key = keys[i];
                 keyXCoordinates[i] = key.mX;
                 keyYCoordinates[i] = key.mY;
                 keyWidths[i] = key.mWidth;
@@ -156,7 +154,6 @@
                                 hitBoxWidth * hitBoxWidth + hitBoxHeight * hitBoxHeight);
                     }
                 }
-                i++;
             }
         } else {
             sweetSpotCenterXs = sweetSpotCenterYs = sweetSpotRadii = null;
@@ -186,17 +183,17 @@
         }
     }
 
-    private void computeNearestNeighbors(int defaultWidth, Set<Key> keys,
+    private void computeNearestNeighbors(int defaultWidth, final Key[] keys,
             TouchPositionCorrection touchPositionCorrection,
             Map<Integer, List<Integer>> additionalProximityChars) {
-        final Map<Integer, Key> keyCodeMap = new HashMap<Integer, Key>();
+        final HashMap<Integer, Key> keyCodeMap = new HashMap<Integer, Key>();
         for (final Key key : keys) {
             keyCodeMap.put(key.mCode, key);
         }
         final int thresholdBase = (int) (defaultWidth * SEARCH_DISTANCE);
         final int threshold = thresholdBase * thresholdBase;
         // Round-up so we don't have any pixels outside the grid
-        final Key[] neighborKeys = new Key[keys.size()];
+        final Key[] neighborKeys = new Key[keys.length];
         final int gridWidth = mGridWidth * mCellWidth;
         final int gridHeight = mGridHeight * mCellHeight;
         for (int x = 0; x < gridWidth; x += mCellWidth) {
diff --git a/java/src/com/android/inputmethod/keyboard/internal/KeyboardIconsSet.java b/java/src/com/android/inputmethod/keyboard/internal/KeyboardIconsSet.java
index ca711ec..9b9c861 100644
--- a/java/src/com/android/inputmethod/keyboard/internal/KeyboardIconsSet.java
+++ b/java/src/com/android/inputmethod/keyboard/internal/KeyboardIconsSet.java
@@ -24,7 +24,6 @@
 import com.android.inputmethod.latin.R;
 
 import java.util.HashMap;
-import java.util.Map;
 
 public class KeyboardIconsSet {
     private static final String TAG = KeyboardIconsSet.class.getSimpleName();
@@ -35,8 +34,9 @@
 
     private final Drawable[] mIcons = new Drawable[NUM_ICONS + 1];
 
-    private static final Map<Integer, Integer> ATTR_ID_TO_ICON_ID = new HashMap<Integer, Integer>();
-    private static final Map<String, Integer> NAME_TO_ICON_ID = new HashMap<String, Integer>();
+    private static final HashMap<Integer, Integer> ATTR_ID_TO_ICON_ID
+            = new HashMap<Integer, Integer>();
+    private static final HashMap<String, Integer> NAME_TO_ICON_ID = new HashMap<String, Integer>();
     private static final String[] ICON_NAMES = new String[NUM_ICONS + 1];
 
     private static final int ATTR_UNDEFINED = 0;
diff --git a/native/jni/com_android_inputmethod_keyboard_ProximityInfo.cpp b/native/jni/com_android_inputmethod_keyboard_ProximityInfo.cpp
index e47a64a..9eb437c 100644
--- a/native/jni/com_android_inputmethod_keyboard_ProximityInfo.cpp
+++ b/native/jni/com_android_inputmethod_keyboard_ProximityInfo.cpp
@@ -50,7 +50,7 @@
     ProximityInfo *proximityInfo = new ProximityInfo(
             localeStr, maxProximityCharsSize, displayWidth,
             displayHeight, gridWidth, gridHeight, mostCommonkeyWidth,
-            (const uint32_t*)proximityChars,
+            (const int32_t*)proximityChars,
             keyCount, (const int32_t*)keyXCoordinates, (const int32_t*)keyYCoordinates,
             (const int32_t*)keyWidths, (const int32_t*)keyHeights, (const int32_t*)keyCharCodes,
             (const float*)sweetSpotCenterXs, (const float*)sweetSpotCenterYs,
diff --git a/native/src/additional_proximity_chars.cpp b/native/src/additional_proximity_chars.cpp
index 401c85a..224f020 100644
--- a/native/src/additional_proximity_chars.cpp
+++ b/native/src/additional_proximity_chars.cpp
@@ -19,23 +19,23 @@
 namespace latinime {
 const std::string AdditionalProximityChars::LOCALE_EN_US("en");
 
-const uint32_t AdditionalProximityChars::EN_US_ADDITIONAL_A[EN_US_ADDITIONAL_A_SIZE] = {
+const int32_t AdditionalProximityChars::EN_US_ADDITIONAL_A[EN_US_ADDITIONAL_A_SIZE] = {
     'e', 'i', 'o', 'u'
 };
 
-const uint32_t AdditionalProximityChars::EN_US_ADDITIONAL_E[EN_US_ADDITIONAL_E_SIZE] = {
+const int32_t AdditionalProximityChars::EN_US_ADDITIONAL_E[EN_US_ADDITIONAL_E_SIZE] = {
     'a', 'i', 'o', 'u'
 };
 
-const uint32_t AdditionalProximityChars::EN_US_ADDITIONAL_I[EN_US_ADDITIONAL_I_SIZE] = {
+const int32_t AdditionalProximityChars::EN_US_ADDITIONAL_I[EN_US_ADDITIONAL_I_SIZE] = {
     'a', 'e', 'o', 'u'
 };
 
-const uint32_t AdditionalProximityChars::EN_US_ADDITIONAL_O[EN_US_ADDITIONAL_O_SIZE] = {
+const int32_t AdditionalProximityChars::EN_US_ADDITIONAL_O[EN_US_ADDITIONAL_O_SIZE] = {
     'a', 'e', 'i', 'u'
 };
 
-const uint32_t AdditionalProximityChars::EN_US_ADDITIONAL_U[EN_US_ADDITIONAL_U_SIZE] = {
+const int32_t AdditionalProximityChars::EN_US_ADDITIONAL_U[EN_US_ADDITIONAL_U_SIZE] = {
     'a', 'e', 'i', 'o'
 };
 }
diff --git a/native/src/additional_proximity_chars.h b/native/src/additional_proximity_chars.h
index e0049d9..e0ecc0e 100644
--- a/native/src/additional_proximity_chars.h
+++ b/native/src/additional_proximity_chars.h
@@ -20,29 +20,31 @@
 #include <stdint.h>
 #include <string>
 
+#include "defines.h"
+
 namespace latinime {
 
 class AdditionalProximityChars {
  private:
     static const std::string LOCALE_EN_US;
     static const int EN_US_ADDITIONAL_A_SIZE = 4;
-    static const uint32_t EN_US_ADDITIONAL_A[];
+    static const int32_t EN_US_ADDITIONAL_A[];
     static const int EN_US_ADDITIONAL_E_SIZE = 4;
-    static const uint32_t EN_US_ADDITIONAL_E[];
+    static const int32_t EN_US_ADDITIONAL_E[];
     static const int EN_US_ADDITIONAL_I_SIZE = 4;
-    static const uint32_t EN_US_ADDITIONAL_I[];
+    static const int32_t EN_US_ADDITIONAL_I[];
     static const int EN_US_ADDITIONAL_O_SIZE = 4;
-    static const uint32_t EN_US_ADDITIONAL_O[];
+    static const int32_t EN_US_ADDITIONAL_O[];
     static const int EN_US_ADDITIONAL_U_SIZE = 4;
-    static const uint32_t EN_US_ADDITIONAL_U[];
+    static const int32_t EN_US_ADDITIONAL_U[];
 
-    static bool isEnLocale(const std::string* locale_str) {
+    static bool isEnLocale(const std::string *locale_str) {
         return locale_str && locale_str->size() >= LOCALE_EN_US.size()
-                && locale_str->compare(0, LOCALE_EN_US.size(), LOCALE_EN_US);
+                && LOCALE_EN_US.compare(0, LOCALE_EN_US.size(), *locale_str);
     }
 
  public:
-    static int getAdditionalCharsSize(const std::string* locale_str, const uint16_t c) {
+    static int getAdditionalCharsSize(const std::string* locale_str, const int32_t c) {
         if (!isEnLocale(locale_str)) {
             return 0;
         }
@@ -62,7 +64,7 @@
         }
     }
 
-    static const uint32_t* getAdditionalChars(const std::string* locale_str, const uint32_t c) {
+    static const int32_t* getAdditionalChars(const std::string *locale_str, const int32_t c) {
         if (!isEnLocale(locale_str)) {
             return 0;
         }
@@ -82,7 +84,7 @@
         }
     }
 
-    static bool hasAdditionalChars(const std::string* locale_str, const uint32_t c) {
+    static bool hasAdditionalChars(const std::string *locale_str, const int32_t c) {
         return getAdditionalCharsSize(locale_str, c) > 0;
     }
 };
diff --git a/native/src/defines.h b/native/src/defines.h
index afa1e04..b0dbffa 100644
--- a/native/src/defines.h
+++ b/native/src/defines.h
@@ -115,6 +115,7 @@
 #define DEBUG_NODE DEBUG_DICT_FULL
 #define DEBUG_TRACE DEBUG_DICT_FULL
 #define DEBUG_PROXIMITY_INFO false
+#define DEBUG_PROXIMITY_CHARS false
 #define DEBUG_CORRECTION false
 #define DEBUG_CORRECTION_FREQ false
 #define DEBUG_WORDS_PRIORITY_QUEUE false
@@ -128,6 +129,7 @@
 #define DEBUG_NODE false
 #define DEBUG_TRACE false
 #define DEBUG_PROXIMITY_INFO false
+#define DEBUG_PROXIMITY_CHARS false
 #define DEBUG_CORRECTION false
 #define DEBUG_CORRECTION_FREQ false
 #define DEBUG_WORDS_PRIORITY_QUEUE false
diff --git a/native/src/proximity_info.cpp b/native/src/proximity_info.cpp
index e590740..dd60ed6 100644
--- a/native/src/proximity_info.cpp
+++ b/native/src/proximity_info.cpp
@@ -37,7 +37,7 @@
 ProximityInfo::ProximityInfo(const std::string localeStr, const int maxProximityCharsSize,
         const int keyboardWidth, const int keyboardHeight, const int gridWidth,
         const int gridHeight, const int mostCommonKeyWidth,
-        const uint32_t *proximityCharsArray, const int keyCount, const int32_t *keyXCoordinates,
+        const int32_t *proximityCharsArray, const int keyCount, const int32_t *keyXCoordinates,
         const int32_t *keyYCoordinates, const int32_t *keyWidths, const int32_t *keyHeights,
         const int32_t *keyCharCodes, const float *sweetSpotCenterXs, const float *sweetSpotCenterYs,
         const float *sweetSpotRadii)
@@ -54,7 +54,7 @@
           mInputXCoordinates(0), mInputYCoordinates(0),
           mTouchPositionCorrectionEnabled(false) {
     const int proximityGridLength = GRID_WIDTH * GRID_HEIGHT * MAX_PROXIMITY_CHARS_SIZE;
-    mProximityCharsArray = new uint32_t[proximityGridLength];
+    mProximityCharsArray = new int32_t[proximityGridLength];
     if (DEBUG_PROXIMITY_INFO) {
         AKLOGI("Create proximity info array %d", proximityGridLength);
     }
@@ -148,35 +148,43 @@
 }
 
 void ProximityInfo::calculateNearbyKeyCodes(
-        const int x, const int y, const uint32_t primaryKey, int *inputCodes) {
+        const int x, const int y, const int32_t primaryKey, int *inputCodes) {
     int insertPos = 0;
     inputCodes[insertPos++] = primaryKey;
     const int startIndex = getStartIndexFromCoordinates(x, y);
     for (int i = 0; i < MAX_PROXIMITY_CHARS_SIZE; ++i) {
-        const uint32_t c = mProximityCharsArray[startIndex + i];
+        const int32_t c = mProximityCharsArray[startIndex + i];
         if (c < KEYCODE_SPACE || c == primaryKey) {
             continue;
         }
-        for (int j = 0; j < KEY_COUNT; ++j) {
-            const bool onKey = isOnKey(j, x, y);
-            const int distance = squaredDistanceToEdge(j, x, y);
-            if (onKey || distance < MOST_COMMON_KEY_WIDTH_SQUARE) {
-                inputCodes[insertPos++] = c;
+        int keyIndex = getKeyIndex(c);
+        const bool onKey = isOnKey(keyIndex, x, y);
+        const int distance = squaredDistanceToEdge(keyIndex, x, y);
+        if (onKey || distance < MOST_COMMON_KEY_WIDTH_SQUARE) {
+            inputCodes[insertPos++] = c;
+            if (insertPos >= MAX_PROXIMITY_CHARS_SIZE) {
+                if (DEBUG_DICT) {
+                    assert(false);
+                }
+                return;
             }
         }
     }
-    const int existingProximitySize = insertPos;
-    for (int i = 0; i < existingProximitySize; ++i) {
-        const uint32_t c = inputCodes[i];
-        const int additionalProximitySize =
-                AdditionalProximityChars::hasAdditionalChars(&mLocaleStr, c);
-        if (additionalProximitySize <= 0) {
-            continue;
+    inputCodes[insertPos++] = ADDITIONAL_PROXIMITY_CHAR_DELIMITER_CODE;
+    if (insertPos >= MAX_PROXIMITY_CHARS_SIZE) {
+        if (DEBUG_DICT) {
+            assert(false);
         }
-        const uint32_t* additionalProximityChars =
-                AdditionalProximityChars::getAdditionalChars(&mLocaleStr, c);
+        return;
+    }
+
+    const int additionalProximitySize =
+            AdditionalProximityChars::getAdditionalCharsSize(&mLocaleStr, primaryKey);
+    if (additionalProximitySize > 0) {
+        const int32_t* additionalProximityChars =
+                AdditionalProximityChars::getAdditionalChars(&mLocaleStr, primaryKey);
         for (int j = 0; j < additionalProximitySize; ++j) {
-            const uint32_t ac = additionalProximityChars[j];
+            const int32_t ac = additionalProximityChars[j];
             int k = 0;
             for (; k < insertPos; ++k) {
                 if ((int)ac == inputCodes[k]) {
@@ -187,9 +195,16 @@
                 continue;
             }
             inputCodes[insertPos++] = ac;
+            if (insertPos >= MAX_PROXIMITY_CHARS_SIZE) {
+                if (DEBUG_DICT) {
+                    assert(false);
+                }
+                return;
+            }
         }
     }
-    // TODO: calculate additional chars
+    // Add a delimiter for the proximity characters
+    inputCodes[insertPos] = 0;
 }
 
 // TODO: Calculate nearby codes here.
@@ -205,8 +220,30 @@
         mPrimaryInputWord[i] = getPrimaryCharAt(i);
     }
     mPrimaryInputWord[inputLength] = 0;
+    if (DEBUG_PROXIMITY_CHARS) {
+        AKLOGI("--- setInputParams");
+    }
     for (int i = 0; i < mInputLength; ++i) {
         const int *proximityChars = getProximityCharsAt(i);
+        const int primaryKey = proximityChars[0];
+        const int x = xCoordinates[i];
+        const int y = yCoordinates[i];
+        if (DEBUG_PROXIMITY_CHARS) {
+            int a = x + y + primaryKey;
+            a += 0;
+            AKLOGI("--- Primary = %c, x = %d, y = %d", primaryKey, x, y);
+            // Keep debug code just in case
+            //int proximities[50];
+            //for (int m = 0; m < 50; ++m) {
+            //proximities[m] = 0;
+            //}
+            //calculateNearbyKeyCodes(x, y, primaryKey, proximities);
+            //for (int l = 0; l < 50 && proximities[l] > 0; ++l) {
+            //if (DEBUG_PROXIMITY_CHARS) {
+            //AKLOGI("--- native Proximity (%d) = %c", l, proximities[l]);
+            //}
+            //}
+        }
         for (int j = 0; j < MAX_PROXIMITY_CHARS_SIZE && proximityChars[j] > 0; ++j) {
             const int currentChar = proximityChars[j];
             const int keyIndex = getKeyIndex(currentChar);
@@ -219,6 +256,9 @@
                         ? EQUIVALENT_CHAR_WITHOUT_DISTANCE_INFO
                         : PROXIMITY_CHAR_WITHOUT_DISTANCE_INFO;
             }
+            if (DEBUG_PROXIMITY_CHARS) {
+                AKLOGI("--- Proximity (%d) = %c", j, currentChar);
+            }
         }
     }
 }
diff --git a/native/src/proximity_info.h b/native/src/proximity_info.h
index 8c342e0..1a47aff 100644
--- a/native/src/proximity_info.h
+++ b/native/src/proximity_info.h
@@ -47,7 +47,7 @@
     ProximityInfo(const std::string localeStr, const int maxProximityCharsSize,
             const int keyboardWidth, const int keybaordHeight, const int gridWidth,
             const int gridHeight, const int mostCommonkeyWidth,
-            const uint32_t *proximityCharsArray, const int keyCount, const int32_t *keyXCoordinates,
+            const int32_t *proximityCharsArray, const int keyCount, const int32_t *keyXCoordinates,
             const int32_t *keyYCoordinates, const int32_t *keyWidths, const int32_t *keyHeights,
             const int32_t *keyCharCodes, const float *sweetSpotCenterXs,
             const float *sweetSpotCenterYs, const float *sweetSpotRadii);
@@ -92,7 +92,7 @@
     bool isOnKey(const int keyId, const int x, const int y);
     int squaredDistanceToEdge(const int keyId, const int x, const int y);
     void calculateNearbyKeyCodes(
-            const int x, const int y, const uint32_t primaryKey, int *inputCodes);
+            const int x, const int y, const int32_t primaryKey, int *inputCodes);
 
     const int MAX_PROXIMITY_CHARS_SIZE;
     const int KEYBOARD_WIDTH;
@@ -109,7 +109,7 @@
     const int *mInputXCoordinates;
     const int *mInputYCoordinates;
     bool mTouchPositionCorrectionEnabled;
-    uint32_t *mProximityCharsArray;
+    int32_t *mProximityCharsArray;
     int *mNormalizedSquaredDistances;
     int32_t mKeyXCoordinates[MAX_KEY_COUNT_IN_A_KEYBOARD];
     int32_t mKeyYCoordinates[MAX_KEY_COUNT_IN_A_KEYBOARD];