Add debug settings for keypress popup animations

Bug: 12928125
Change-Id: I49faab754c7d1dcf4a791dfc535d3a78b62ce67a

java/res/values/attrs.xml

@@ -111,10 +111,6 @@
         <attr name="keyPreviewOffset" format="dimension" />
         <!-- Height of the key press feedback popup. -->
         <attr name="keyPreviewHeight" format="dimension" />
-        <!-- Duration of key preview popup zoom in animation in millisecond -->
-        <attr name="keyPreviewZoomInDuration" format="integer" />
-        <!-- Duration of key preview popup zoom out animation in millisecond -->
-        <attr name="keyPreviewZoomOutDuration" format="integer" />
         <!-- Delay after key releasing and key press feedback dismissing in millisecond -->
         <attr name="keyPreviewLingerTimeout" format="integer" />
         <!-- Layout resource for more keys keyboard -->

java/res/values/config-common.xml

@@ -35,8 +35,10 @@
 
     <integer name="config_ignore_alt_code_key_timeout">350</integer>
 
-    <integer name="config_key_preview_zoom_in_duration">35</integer>
+    <integer name="config_key_preview_show_up_duration">35</integer>
-    <integer name="config_key_preview_zoom_out_duration">40</integer>
+    <integer name="config_key_preview_dismiss_duration">40</integer>
+    <fraction name="config_key_preview_show_up_start_scale">70%</fraction>
+    <fraction name="config_key_preview_dismiss_end_scale">70%</fraction>
     <integer name="config_key_preview_linger_timeout">70</integer>
     <!-- Suppress showing key preview duration after batch input in millisecond -->
     <integer name="config_suppress_key_preview_after_batch_input_duration">1000</integer>

java/res/values/strings.xml

@@ -486,6 +486,14 @@ mobile devices. [CHAR LIMIT=25] -->
     <string name="prefs_keypress_vibration_duration_settings">Keypress vibration duration</string>
     <!-- Title of the settings for keypress sound volume [CHAR LIMIT=35] -->
     <string name="prefs_keypress_sound_volume_settings">Keypress sound volume</string>
+    <!-- Title of the settings for key popup show up animation duration (in milliseconds) [CHAR LIMIT=35] -->
+    <string name="prefs_key_popup_show_up_duration_settings" translatable="false">Key popup show up duration</string>
+    <!-- Title of the settings for key popup dismiss animation duration (in milliseconds) [CHAR LIMIT=35] -->
+    <string name="prefs_key_popup_dismiss_duration_settings" translatable="false">Key popup dismiss duration</string>
+    <!-- Title of the settings for key popup show up animation start scale (in percentile) [CHAR LIMIT=35] -->
+    <string name="prefs_key_popup_show_up_start_scale_settings" translatable="false">Key popup show up start scale</string>
+    <!-- Title of the settings for key popup dismiss animation end scale (in percentile) [CHAR LIMIT=35] -->
+    <string name="prefs_key_popup_dismiss_end_scale_settings" translatable="false">Key popup dismiss end scale</string>
     <!-- Title of the settings for reading an external dictionary file -->
     <string name="prefs_read_external_dictionary">Read external dictionary file</string>
     <!-- Title of the settings for using only personalization dictionary -->

java/res/values/themes-common.xml

@@ -77,8 +77,6 @@
         <item name="ignoreAltCodeKeyTimeout">@integer/config_ignore_alt_code_key_timeout</item>
         <item name="keyPreviewLayout">@layout/key_preview</item>
         <item name="keyPreviewHeight">@dimen/config_key_preview_height</item>
-        <item name="keyPreviewZoomInDuration">@integer/config_key_preview_zoom_in_duration</item>
-        <item name="keyPreviewZoomOutDuration">@integer/config_key_preview_zoom_out_duration</item>
         <item name="keyPreviewLingerTimeout">@integer/config_key_preview_linger_timeout</item>
         <item name="moreKeysKeyboardLayout">@layout/more_keys_keyboard</item>
         <item name="showMoreKeysKeyboardAtTouchedPoint">@bool/config_show_more_keys_keyboard_at_touched_point</item>

java/res/xml/prefs_for_debug.xml

@@ -14,17 +14,18 @@
      limitations under the License.
 -->
 
-<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
+<PreferenceScreen
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:latin="http://schemas.android.com/apk/res/com.android.inputmethod.latin"
     android:title="@string/prefs_debug_mode"
-        android:key="english_ime_debug_settings">
+    android:key="english_ime_debug_settings"
-
+>
     <CheckBoxPreference
         android:key="enable_logging"
         android:title="@string/prefs_enable_log"
         android:summary="@string/prefs_description_log"
         android:persistent="true"
         android:defaultValue="false" />
-
     <ListPreference
         android:key="pref_keyboard_layout_20110916"
         android:title="@string/keyboard_layout"
@@ -33,49 +34,55 @@
         android:entryValues="@array/keyboard_layout_modes_values"
         android:entries="@array/keyboard_layout_modes"
         android:defaultValue="@string/config_default_keyboard_theme_index" />
-
     <CheckBoxPreference
         android:key="debug_mode"
         android:title="@string/prefs_debug_mode"
         android:persistent="true"
         android:defaultValue="false" />
-
     <CheckBoxPreference
         android:key="force_non_distinct_multitouch"
         android:title="@string/prefs_force_non_distinct_multitouch"
         android:persistent="true"
         android:defaultValue="false" />
-
     <CheckBoxPreference
         android:key="usability_study_mode"
         android:title="@string/prefs_usability_study_mode"
         android:persistent="true"
         android:defaultValue="false" />
-
+    <com.android.inputmethod.latin.settings.SeekBarDialogPreference
+        android:key="pref_key_preview_show_up_start_scale"
+        android:title="@string/prefs_key_popup_show_up_start_scale_settings"
+        latin:maxValue="100" /> <!-- percent -->
+    <com.android.inputmethod.latin.settings.SeekBarDialogPreference
+        android:key="pref_key_preview_dismiss_end_scale"
+        android:title="@string/prefs_key_popup_dismiss_end_scale_settings"
+        latin:maxValue="100" /> <!-- percent -->
+    <com.android.inputmethod.latin.settings.SeekBarDialogPreference
+        android:key="pref_key_preview_show_up_duration"
+        android:title="@string/prefs_key_popup_show_up_duration_settings"
+        latin:maxValue="100" /> <!-- milliseconds -->
+    <com.android.inputmethod.latin.settings.SeekBarDialogPreference
+        android:key="pref_key_preview_dismiss_duration"
+        android:title="@string/prefs_key_popup_dismiss_duration_settings"
+        latin:maxValue="100" /> <!-- milliseconds -->
     <CheckBoxPreference
         android:defaultValue="false"
         android:key="use_only_personalization_dictionary_for_debug"
         android:persistent="true"
         android:title="@string/prefs_use_only_personalization_dictionary" />
-
     <PreferenceScreen
         android:key="read_external_dictionary"
         android:title="@string/prefs_read_external_dictionary" />
-
     <PreferenceScreen
         android:key="dump_contacts_dict"
         android:title="@string/prefs_dump_contacts_dict" />
-
     <PreferenceScreen
         android:key="dump_user_dict"
         android:title="@string/prefs_dump_user_dict" />
-
     <PreferenceScreen
         android:key="dump_user_history_dict"
         android:title="@string/prefs_dump_user_history_dict" />
-
     <PreferenceScreen
         android:key="dump_personalization_dict"
         android:title="@string/prefs_dump_personalization_dict" />
-
 </PreferenceScreen>

java/src/com/android/inputmethod/keyboard/KeyboardSwitcher.java

@@ -37,6 +37,7 @@ import com.android.inputmethod.latin.R;
 import com.android.inputmethod.latin.RichInputMethodManager;
 import com.android.inputmethod.latin.SubtypeSwitcher;
 import com.android.inputmethod.latin.WordComposer;
+import com.android.inputmethod.latin.settings.DebugSettings;
 import com.android.inputmethod.latin.settings.Settings;
 import com.android.inputmethod.latin.settings.SettingsValues;
 import com.android.inputmethod.latin.utils.ResourceUtils;
@@ -80,6 +81,7 @@ public final class KeyboardSwitcher implements KeyboardState.SwitchActions {
     private KeyboardState mState;
 
     private KeyboardLayoutSet mKeyboardLayoutSet;
+    private SettingsValues mCurrentSettingsValues;
 
     /** mIsAutoCorrectionActive indicates that auto corrected word will be input instead of
      * what user actually typed. */
@@ -158,6 +160,7 @@ public final class KeyboardSwitcher implements KeyboardState.SwitchActions {
                 settingsValues.mShowsVoiceInputKey,
                 settingsValues.isLanguageSwitchKeyEnabled());
         mKeyboardLayoutSet = builder.build();
+        mCurrentSettingsValues = settingsValues;
         try {
             mState.onLoadKeyboard();
         } catch (KeyboardLayoutSetException e) {
@@ -189,8 +192,13 @@ public final class KeyboardSwitcher implements KeyboardState.SwitchActions {
         keyboardView.setKeyboard(keyboard);
         mCurrentInputView.setKeyboardTopPadding(keyboard.mTopPadding);
         keyboardView.setKeyPreviewPopupEnabled(
-                Settings.readKeyPreviewPopupEnabled(mPrefs, mResources),
+                mCurrentSettingsValues.mKeyPreviewPopupOn,
-                Settings.readKeyPreviewPopupDismissDelay(mPrefs, mResources));
+                mCurrentSettingsValues.mKeyPreviewPopupDismissDelay);
+        keyboardView.setKeyPreviewAnimationParams(
+                mCurrentSettingsValues.mKeyPreviewShowUpStartScale,
+                mCurrentSettingsValues.mKeyPreviewShowUpDuration,
+                mCurrentSettingsValues.mKeyPreviewDismissEndScale,
+                mCurrentSettingsValues.mKeyPreviewDismissDuration);
         keyboardView.updateAutoCorrectionState(mIsAutoCorrectionActive);
         keyboardView.updateShortcutKey(mSubtypeSwitcher.isShortcutImeReady());
         final boolean subtypeChanged = (oldKeyboard == null)

java/src/com/android/inputmethod/keyboard/MainKeyboardView.java

@@ -421,6 +421,12 @@ public final class MainKeyboardView extends KeyboardView implements PointerTrack
         mKeyPreviewDrawParams.setPopupEnabled(previewEnabled, delay);
     }
 
+    public void setKeyPreviewAnimationParams(final float showUpStartScale, final int showUpDuration,
+            final float dismissEndScale, final int dismissDuration) {
+        mKeyPreviewDrawParams.setAnimationParams(
+                showUpStartScale, showUpDuration, dismissEndScale, dismissDuration);
+    }
+
     private void locatePreviewPlacerView() {
         if (mDrawingPreviewPlacerView.getParent() != null) {
             return;

java/src/com/android/inputmethod/keyboard/internal/KeyPreviewChoreographer.java

@@ -100,7 +100,7 @@ public final class KeyPreviewChoreographer {
         if (withAnimation) {
             if (tag instanceof KeyPreviewAnimations) {
                 final KeyPreviewAnimations animation = (KeyPreviewAnimations)tag;
-                animation.startZoomOut();
+                animation.startDismiss();
             }
             return;
         }
@@ -198,87 +198,87 @@ public final class KeyPreviewChoreographer {
         }
 
         // Show preview with animation.
-        final Animator zoomIn = createZoomInAniation(key, previewTextView);
+        final Animator showUpAnimation = createShowUpAniation(key, previewTextView);
-        final Animator zoomOut = createZoomOutAnimation(key, previewTextView);
+        final Animator dismissAnimation = createDismissAnimation(key, previewTextView);
-        final KeyPreviewAnimations animation = new KeyPreviewAnimations(zoomIn, zoomOut);
+        final KeyPreviewAnimations animation = new KeyPreviewAnimations(
+                showUpAnimation, dismissAnimation);
         previewTextView.setTag(animation);
-        animation.startZoomIn();
+        animation.startShowUp();
     }
 
-    // TODO: Move these parameters to resources or preferences.
+    private static final float KEY_PREVIEW_SHOW_UP_END_SCALE = 1.0f;
-    private static final float KEY_PREVIEW_START_ZOOM_IN_SCALE = 0.7f;
-    private static final float KEY_PREVIEW_END_ZOOM_IN_SCALE = 1.0f;
-    private static final float KEY_PREVIEW_END_ZOOM_OUT_SCALE = 0.7f;
     private static final AccelerateInterpolator ACCELERATE_INTERPOLATOR =
             new AccelerateInterpolator();
     private static final DecelerateInterpolator DECELERATE_INTERPOLATOR =
             new DecelerateInterpolator();
 
-    private Animator createZoomInAniation(final Key key, final TextView previewTextView) {
+    private Animator createShowUpAniation(final Key key, final TextView previewTextView) {
+        // TODO: Optimization for no scale animation and no duration.
         final ObjectAnimator scaleXAnimation = ObjectAnimator.ofFloat(
-                previewTextView, View.SCALE_X, KEY_PREVIEW_START_ZOOM_IN_SCALE,
+                previewTextView, View.SCALE_X, mParams.getShowUpStartScale(),
-                KEY_PREVIEW_END_ZOOM_IN_SCALE);
+                KEY_PREVIEW_SHOW_UP_END_SCALE);
         final ObjectAnimator scaleYAnimation = ObjectAnimator.ofFloat(
-                previewTextView, View.SCALE_Y, KEY_PREVIEW_START_ZOOM_IN_SCALE,
+                previewTextView, View.SCALE_Y, mParams.getShowUpStartScale(),
-                KEY_PREVIEW_END_ZOOM_IN_SCALE);
+                KEY_PREVIEW_SHOW_UP_END_SCALE);
-        final AnimatorSet zoomInAnimation = new AnimatorSet();
+        final AnimatorSet showUpAnimation = new AnimatorSet();
-        zoomInAnimation.play(scaleXAnimation).with(scaleYAnimation);
+        showUpAnimation.play(scaleXAnimation).with(scaleYAnimation);
-        // TODO: Implement preference option to control key preview animation duration.
+        showUpAnimation.setDuration(mParams.getShowUpDuration());
-        zoomInAnimation.setDuration(mParams.mZoomInDuration);
+        showUpAnimation.setInterpolator(DECELERATE_INTERPOLATOR);
-        zoomInAnimation.setInterpolator(DECELERATE_INTERPOLATOR);
+        showUpAnimation.addListener(new AnimatorListenerAdapter() {
-        zoomInAnimation.addListener(new AnimatorListenerAdapter() {
             @Override
             public void onAnimationStart(final Animator animation) {
                 showKeyPreview(key, previewTextView, false /* withAnimation */);
             }
         });
-        return zoomInAnimation;
+        return showUpAnimation;
     }
 
-    private Animator createZoomOutAnimation(final Key key, final TextView previewTextView) {
+    private Animator createDismissAnimation(final Key key, final TextView previewTextView) {
+        // TODO: Optimization for no scale animation and no duration.
         final ObjectAnimator scaleXAnimation = ObjectAnimator.ofFloat(
-                previewTextView, View.SCALE_X, KEY_PREVIEW_END_ZOOM_OUT_SCALE);
+                previewTextView, View.SCALE_X, mParams.getDismissEndScale());
         final ObjectAnimator scaleYAnimation = ObjectAnimator.ofFloat(
-                previewTextView, View.SCALE_Y, KEY_PREVIEW_END_ZOOM_OUT_SCALE);
+                previewTextView, View.SCALE_Y, mParams.getDismissEndScale());
-        final AnimatorSet zoomOutAnimation = new AnimatorSet();
+        final AnimatorSet dismissAnimation = new AnimatorSet();
-        zoomOutAnimation.play(scaleXAnimation).with(scaleYAnimation);
+        dismissAnimation.play(scaleXAnimation).with(scaleYAnimation);
-        // TODO: Implement preference option to control key preview animation duration.
+        final int dismissDuration = Math.min(
-        final int zoomOutDuration = Math.min(mParams.mZoomOutDuration, mParams.getLingerTimeout());
+                mParams.getDismissDuration(), mParams.getLingerTimeout());
-        zoomOutAnimation.setDuration(zoomOutDuration);
+        dismissAnimation.setDuration(dismissDuration);
-        zoomOutAnimation.setInterpolator(ACCELERATE_INTERPOLATOR);
+        dismissAnimation.setInterpolator(ACCELERATE_INTERPOLATOR);
-        zoomOutAnimation.addListener(new AnimatorListenerAdapter() {
+        dismissAnimation.addListener(new AnimatorListenerAdapter() {
             @Override
             public void onAnimationEnd(final Animator animation) {
                 dismissKeyPreview(key, false /* withAnimation */);
             }
         });
-        return zoomOutAnimation;
+        return dismissAnimation;
     }
 
     private static class KeyPreviewAnimations extends AnimatorListenerAdapter {
-        private final Animator mZoomIn;
+        private final Animator mShowUpAnimation;
-        private final Animator mZoomOut;
+        private final Animator mDismissAnimation;
 
-        public KeyPreviewAnimations(final Animator zoomIn, final Animator zoomOut) {
+        public KeyPreviewAnimations(final Animator showUpAnimation,
-            mZoomIn = zoomIn;
+                final Animator dismissAnimation) {
-            mZoomOut = zoomOut;
+            mShowUpAnimation = showUpAnimation;
+            mDismissAnimation = dismissAnimation;
         }
 
-        public void startZoomIn() {
+        public void startShowUp() {
-            mZoomIn.start();
+            mShowUpAnimation.start();
         }
 
-        public void startZoomOut() {
+        public void startDismiss() {
-            if (mZoomIn.isRunning()) {
+            if (mShowUpAnimation.isRunning()) {
-                mZoomIn.addListener(this);
+                mShowUpAnimation.addListener(this);
                 return;
             }
-            mZoomOut.start();
+            mDismissAnimation.start();
         }
 
         @Override
         public void onAnimationEnd(final Animator animation) {
-            mZoomOut.start();
+            mDismissAnimation.start();
         }
     }
 }

java/src/com/android/inputmethod/keyboard/internal/KeyPreviewDrawParams.java

@@ -26,9 +26,10 @@ public final class KeyPreviewDrawParams {
     public final int mLayoutId;
     public final int mPreviewOffset;
     public final int mPreviewHeight;
-    // TODO: Move those parameters to preferences.
+    private int mShowUpDuration;
-    public final int mZoomInDuration;
+    private int mDismissDuration;
-    public final int mZoomOutDuration;
+    private float mShowUpStartScale;
+    private float mDismissEndScale;
     private int mLingerTimeout;
     private boolean mShowPopup = true;
 
@@ -69,10 +70,6 @@ public final class KeyPreviewDrawParams {
         if (mLayoutId == 0) {
             mShowPopup = false;
         }
-        mZoomInDuration = mainKeyboardViewAttr.getInt(
-                R.styleable.MainKeyboardView_keyPreviewZoomInDuration, 0);
-        mZoomOutDuration = mainKeyboardViewAttr.getInt(
-                R.styleable.MainKeyboardView_keyPreviewZoomOutDuration, 0);
     }
 
     public void setVisibleOffset(final int previewVisibleOffset) {
@@ -117,4 +114,28 @@ public final class KeyPreviewDrawParams {
     public int getLingerTimeout() {
         return mLingerTimeout;
     }
+
+    public void setAnimationParams(final float showUpStartScale, final int showUpDuration,
+            final float dismissEndScale, final int dismissDuration) {
+        mShowUpStartScale = showUpStartScale;
+        mShowUpDuration = showUpDuration;
+        mDismissEndScale = dismissEndScale;
+        mDismissDuration = dismissDuration;
+    }
+
+    public float getShowUpStartScale() {
+        return mShowUpStartScale;
+    }
+
+    public int getShowUpDuration() {
+        return mShowUpDuration;
+    }
+
+    public float getDismissEndScale() {
+        return mDismissEndScale;
+    }
+
+    public int getDismissDuration() {
+        return mDismissDuration;
+    }
 }

java/src/com/android/inputmethod/latin/settings/DebugSettings.java

@@ -18,6 +18,7 @@ package com.android.inputmethod.latin.settings;
 
 import android.content.Intent;
 import android.content.SharedPreferences;
+import android.content.res.Resources;
 import android.os.Bundle;
 import android.os.Process;
 import android.preference.CheckBoxPreference;
@@ -32,6 +33,7 @@ import com.android.inputmethod.latin.LatinImeLogger;
 import com.android.inputmethod.latin.R;
 import com.android.inputmethod.latin.debug.ExternalDictionaryGetterForDebug;
 import com.android.inputmethod.latin.utils.ApplicationUtils;
+import com.android.inputmethod.latin.utils.ResourceUtils;
 
 public final class DebugSettings extends PreferenceFragment
         implements SharedPreferences.OnSharedPreferenceChangeListener {
@@ -42,6 +44,14 @@ public final class DebugSettings extends PreferenceFragment
     public static final String PREF_STATISTICS_LOGGING = "enable_logging";
     public static final String PREF_USE_ONLY_PERSONALIZATION_DICTIONARY_FOR_DEBUG =
             "use_only_personalization_dictionary_for_debug";
+    public static final String PREF_KEY_PREVIEW_SHOW_UP_START_SCALE =
+            "pref_key_preview_show_up_start_scale";
+    public static final String PREF_KEY_PREVIEW_DISMISS_END_SCALE =
+            "pref_key_preview_dismiss_end_scale";
+    public static final String PREF_KEY_PREVIEW_SHOW_UP_DURATION =
+            "pref_key_preview_show_up_duration";
+    public static final String PREF_KEY_PREVIEW_DISMISS_DURATION =
+            "pref_key_preview_dismiss_duration";
     private static final String PREF_READ_EXTERNAL_DICTIONARY = "read_external_dictionary";
     private static final String PREF_DUMP_CONTACTS_DICT = "dump_contacts_dict";
     private static final String PREF_DUMP_USER_DICT = "dump_user_dict";
@@ -101,6 +111,17 @@ public final class DebugSettings extends PreferenceFragment
                 dictDumpPrefClickListener);
         findPreference(PREF_DUMP_PERSONALIZATION_DICT).setOnPreferenceClickListener(
                 dictDumpPrefClickListener);
+        final Resources res = getResources();
+        setupKeyPreviewAnimationDuration(prefs, res, PREF_KEY_PREVIEW_SHOW_UP_DURATION,
+                res.getInteger(R.integer.config_key_preview_show_up_duration));
+        setupKeyPreviewAnimationDuration(prefs, res, PREF_KEY_PREVIEW_DISMISS_DURATION,
+                res.getInteger(R.integer.config_key_preview_dismiss_duration));
+        setupKeyPreviewAnimationScale(prefs, res, PREF_KEY_PREVIEW_SHOW_UP_START_SCALE,
+                ResourceUtils.getFloatFromFraction(
+                        res, R.fraction.config_key_preview_show_up_start_scale));
+        setupKeyPreviewAnimationScale(prefs, res, PREF_KEY_PREVIEW_DISMISS_END_SCALE,
+                ResourceUtils.getFloatFromFraction(
+                        res, R.fraction.config_key_preview_dismiss_end_scale));
 
         mServiceNeedsRestart = false;
         mDebugMode = (CheckBoxPreference) findPreference(PREF_DEBUG_MODE);
@@ -180,4 +201,92 @@ public final class DebugSettings extends PreferenceFragment
             mDebugMode.setSummary(version);
         }
     }
+
+    private void setupKeyPreviewAnimationScale(final SharedPreferences sp, final Resources res,
+            final String prefKey, final float defaultValue) {
+        final SeekBarDialogPreference pref = (SeekBarDialogPreference)findPreference(prefKey);
+        if (pref == null) {
+            return;
+        }
+        pref.setInterface(new SeekBarDialogPreference.ValueProxy() {
+            private static final float PERCENTAGE_FLOAT = 100.0f;
+
+            private float getValueFromPercentage(final int percentage) {
+                return percentage / PERCENTAGE_FLOAT;
+            }
+
+            private int getPercentageFromValue(final float floatValue) {
+                return (int)(floatValue * PERCENTAGE_FLOAT);
+            }
+
+            @Override
+            public void writeValue(final int value, final String key) {
+                sp.edit().putFloat(key, getValueFromPercentage(value)).apply();
+            }
+
+            @Override
+            public void writeDefaultValue(final String key) {
+                sp.edit().remove(key).apply();
+            }
+
+            @Override
+            public int readValue(final String key) {
+                return getPercentageFromValue(
+                        Settings.readKeyPreviewAnimationScale(sp, key, defaultValue));
+            }
+
+            @Override
+            public int readDefaultValue(final String key) {
+                return getPercentageFromValue(defaultValue);
+            }
+
+            @Override
+            public String getValueText(final int value) {
+                if (value < 0) {
+                    return res.getString(R.string.settings_system_default);
+                }
+                return String.format("%d%%", value);
+            }
+
+            @Override
+            public void feedbackValue(final int value) {}
+        });
+    }
+
+    private void setupKeyPreviewAnimationDuration(final SharedPreferences sp, final Resources res,
+            final String prefKey, final int defaultValue) {
+        final SeekBarDialogPreference pref = (SeekBarDialogPreference)findPreference(prefKey);
+        if (pref == null) {
+            return;
+        }
+        pref.setInterface(new SeekBarDialogPreference.ValueProxy() {
+            @Override
+            public void writeValue(final int value, final String key) {
+                sp.edit().putInt(key, value).apply();
+            }
+
+            @Override
+            public void writeDefaultValue(final String key) {
+                sp.edit().remove(key).apply();
+            }
+
+            @Override
+            public int readValue(final String key) {
+                return Settings.readKeyPreviewAnimationDuration(sp, key, defaultValue);
+            }
+
+            @Override
+            public int readDefaultValue(final String key) {
+                return defaultValue;
+            }
+
+            @Override
+            public String getValueText(final int value) {
+                return res.getString(R.string.abbreviation_unit_milliseconds, value);
+            }
+
+            @Override
+            public void feedbackValue(final int value) {}
+        });
+    }
 }

java/src/com/android/inputmethod/latin/settings/Settings.java

@@ -107,6 +107,9 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
     public static final String PREF_EMOJI_CATEGORY_LAST_TYPED_ID = "emoji_category_last_typed_id";
     public static final String PREF_LAST_SHOWN_EMOJI_CATEGORY_ID = "last_shown_emoji_category_id";
 
+    private static final float UNDEFINED_PREFERENCE_VALUE_FLOAT = -1.0f;
+    private static final int UNDEFINED_PREFERENCE_VALUE_INT = -1;
+
     private Context mContext;
     private Resources mRes;
     private SharedPreferences mPrefs;
@@ -301,8 +304,10 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
 
     public static float readKeypressSoundVolume(final SharedPreferences prefs,
             final Resources res) {
-        final float volume = prefs.getFloat(PREF_KEYPRESS_SOUND_VOLUME, -1.0f);
+        final float volume = prefs.getFloat(
-        return (volume >= 0) ? volume : readDefaultKeypressSoundVolume(res);
+                PREF_KEYPRESS_SOUND_VOLUME, UNDEFINED_PREFERENCE_VALUE_FLOAT);
+        return (volume != UNDEFINED_PREFERENCE_VALUE_FLOAT) ? volume
+                : readDefaultKeypressSoundVolume(res);
     }
 
     public static float readDefaultKeypressSoundVolume(final Resources res) {
@@ -312,8 +317,10 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
 
     public static int readKeyLongpressTimeout(final SharedPreferences prefs,
             final Resources res) {
-        final int ms = prefs.getInt(PREF_KEY_LONGPRESS_TIMEOUT, -1);
+        final int milliseconds = prefs.getInt(
-        return (ms >= 0) ? ms : readDefaultKeyLongpressTimeout(res);
+                PREF_KEY_LONGPRESS_TIMEOUT, UNDEFINED_PREFERENCE_VALUE_INT);
+        return (milliseconds != UNDEFINED_PREFERENCE_VALUE_INT) ? milliseconds
+                : readDefaultKeyLongpressTimeout(res);
     }
 
     public static int readDefaultKeyLongpressTimeout(final Resources res) {
@@ -322,8 +329,10 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
 
     public static int readKeypressVibrationDuration(final SharedPreferences prefs,
             final Resources res) {
-        final int ms = prefs.getInt(PREF_VIBRATION_DURATION_SETTINGS, -1);
+        final int milliseconds = prefs.getInt(
-        return (ms >= 0) ? ms : readDefaultKeypressVibrationDuration(res);
+                PREF_VIBRATION_DURATION_SETTINGS, UNDEFINED_PREFERENCE_VALUE_INT);
+        return (milliseconds != UNDEFINED_PREFERENCE_VALUE_INT) ? milliseconds
+                : readDefaultKeypressVibrationDuration(res);
     }
 
     public static int readDefaultKeypressVibrationDuration(final Resources res) {
@@ -335,6 +344,18 @@ public final class Settings implements SharedPreferences.OnSharedPreferenceChang
         return prefs.getBoolean(DebugSettings.PREF_USABILITY_STUDY_MODE, true);
     }
 
+    public static float readKeyPreviewAnimationScale(final SharedPreferences prefs,
+            final String prefKey, final float defaultValue) {
+        final float fraction = prefs.getFloat(prefKey, UNDEFINED_PREFERENCE_VALUE_FLOAT);
+        return (fraction != UNDEFINED_PREFERENCE_VALUE_FLOAT) ? fraction : defaultValue;
+    }
+
+    public static int readKeyPreviewAnimationDuration(final SharedPreferences prefs,
+            final String prefKey, final int defaultValue) {
+        final int milliseconds = prefs.getInt(prefKey, UNDEFINED_PREFERENCE_VALUE_INT);
+        return (milliseconds != UNDEFINED_PREFERENCE_VALUE_INT) ? milliseconds : defaultValue;
+    }
+
     public static boolean readUseFullscreenMode(final Resources res) {
         return res.getBoolean(R.bool.config_use_fullscreen_mode);
     }

java/src/com/android/inputmethod/latin/settings/SettingsValues.java

@@ -29,6 +29,7 @@ import com.android.inputmethod.latin.InputAttributes;
 import com.android.inputmethod.latin.R;
 import com.android.inputmethod.latin.RichInputMethodManager;
 import com.android.inputmethod.latin.utils.AsyncResultHolder;
+import com.android.inputmethod.latin.utils.ResourceUtils;
 import com.android.inputmethod.latin.utils.TargetPackageInfoGetterTask;
 
 import java.util.Arrays;
@@ -93,6 +94,10 @@ public final class SettingsValues {
 
     // Debug settings
     public final boolean mIsInternal;
+    public final int mKeyPreviewShowUpDuration;
+    public final int mKeyPreviewDismissDuration;
+    public final float mKeyPreviewShowUpStartScale;
+    public final float mKeyPreviewDismissEndScale;
 
     public SettingsValues(final Context context, final SharedPreferences prefs, final Resources res,
             final InputAttributes inputAttributes) {
@@ -149,6 +154,20 @@ public final class SettingsValues {
         AdditionalFeaturesSettingUtils.readAdditionalFeaturesPreferencesIntoArray(
                 prefs, mAdditionalFeaturesSettingValues);
         mIsInternal = Settings.isInternal(prefs);
+        mKeyPreviewShowUpDuration = Settings.readKeyPreviewAnimationDuration(
+                prefs, DebugSettings.PREF_KEY_PREVIEW_SHOW_UP_DURATION,
+                res.getInteger(R.integer.config_key_preview_show_up_duration));
+        mKeyPreviewDismissDuration = Settings.readKeyPreviewAnimationDuration(
+                prefs, DebugSettings.PREF_KEY_PREVIEW_DISMISS_DURATION,
+                res.getInteger(R.integer.config_key_preview_dismiss_duration));
+        mKeyPreviewShowUpStartScale = Settings.readKeyPreviewAnimationScale(
+                prefs, DebugSettings.PREF_KEY_PREVIEW_SHOW_UP_START_SCALE,
+                ResourceUtils.getFloatFromFraction(
+                        res, R.fraction.config_key_preview_show_up_start_scale));
+        mKeyPreviewDismissEndScale = Settings.readKeyPreviewAnimationScale(
+                prefs, DebugSettings.PREF_KEY_PREVIEW_DISMISS_END_SCALE,
+                ResourceUtils.getFloatFromFraction(
+                        res, R.fraction.config_key_preview_dismiss_end_scale));
         mUseOnlyPersonalizationDictionaryForDebug = prefs.getBoolean(
                 DebugSettings.PREF_USE_ONLY_PERSONALIZATION_DICTIONARY_FOR_DEBUG, false);
         mDisplayOrientation = res.getConfiguration().orientation;

java/src/com/android/inputmethod/latin/utils/ResourceUtils.java

@@ -260,6 +260,10 @@ public final class ResourceUtils {
         return dimension >= 0;
     }
 
+    public static float getFloatFromFraction(final Resources res, final int fractionResId) {
+        return res.getFraction(fractionResId, 1, 1);
+    }
+
     public static float getFraction(final TypedArray a, final int index, final float defValue) {
         final TypedValue value = a.peekValue(index);
         if (value == null || !isFractionValue(value)) {