Add keyboard shadow

This CL sets 8dp elevation ot input view in order to cast a shadow
onto underlying application.

Bug: 16210054
Change-Id: I7779c63612fc88e24dde65de3e4e7a45b9d1762f
diff --git a/java/res/layout/input_view.xml b/java/res/layout/input_view.xml
index 46551f6..ae3c19d 100644
--- a/java/res/layout/input_view.xml
+++ b/java/res/layout/input_view.xml
@@ -21,7 +21,8 @@
 <com.android.inputmethod.latin.InputView
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
-    android:layout_height="wrap_content">
+    android:layout_height="wrap_content"
+    style="?attr/inputViewStyle">
     <include
         android:id="@+id/main_keyboard_frame"
         layout="@layout/main_keyboard_frame" />
diff --git a/java/res/values-v21/themes-lxx.xml b/java/res/values-v21/themes-lxx.xml
new file mode 100644
index 0000000..5a6017c
--- /dev/null
+++ b/java/res/values-v21/themes-lxx.xml
@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+**
+** Copyright 2014, 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:android="http://schemas.android.com/apk/res/android">
+    <style
+        name="InputView.LXX"
+        parent="InputView"
+    >
+        <item name="android:elevation">8dp</item>
+    </style>
+</resources>
diff --git a/java/res/values/attrs.xml b/java/res/values/attrs.xml
index f2072fd..be35d13 100644
--- a/java/res/values/attrs.xml
+++ b/java/res/values/attrs.xml
@@ -20,6 +20,8 @@
 
 <resources>
     <declare-styleable name="KeyboardTheme">
+        <!-- InputView style -->
+        <attr name="inputViewStyle" format="reference" />
         <!-- Keyboard style -->
         <attr name="keyboardStyle" format="reference" />
         <!-- KeyboardView style -->
diff --git a/java/res/values/themes-common.xml b/java/res/values/themes-common.xml
index 110f6b7..f7cb10f 100644
--- a/java/res/values/themes-common.xml
+++ b/java/res/values/themes-common.xml
@@ -20,6 +20,7 @@
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
     <style name="KeyboardIcons" />
+    <style name="InputView" />
     <!-- Default theme values -->
     <style name="Keyboard">
         <item name="rowHeight">25%p</item>
diff --git a/java/res/values/themes-holo.xml b/java/res/values/themes-holo.xml
index 9f1bd2f..efac656 100644
--- a/java/res/values/themes-holo.xml
+++ b/java/res/values/themes-holo.xml
@@ -19,6 +19,10 @@
 -->
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
+    <style
+        name="InputView.Holo"
+        parent="InputView"
+    />
     <!-- Holo KeyboardView theme (ICS and KLP) -->
     <style
         name="KeyboardView.Holo"
diff --git a/java/res/values/themes-ics.xml b/java/res/values/themes-ics.xml
index bfbac0a..ecf40e4 100644
--- a/java/res/values/themes-ics.xml
+++ b/java/res/values/themes-ics.xml
@@ -20,6 +20,7 @@
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
     <style name="KeyboardTheme.ICS" parent="KeyboardIcons.Holo">
+        <item name="inputViewStyle">@style/InputView.Holo</item>
         <item name="keyboardStyle">@style/Keyboard.ICS</item>
         <item name="keyboardViewStyle">@style/KeyboardView.ICS</item>
         <item name="mainKeyboardViewStyle">@style/MainKeyboardView.ICS</item>
diff --git a/java/res/values/themes-klp.xml b/java/res/values/themes-klp.xml
index 36b1fc1..de1cd9b 100644
--- a/java/res/values/themes-klp.xml
+++ b/java/res/values/themes-klp.xml
@@ -20,6 +20,7 @@
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
     <style name="KeyboardTheme.KLP" parent="KeyboardIcons.Holo">
+        <item name="inputViewStyle">@style/InputView.Holo</item>
         <item name="keyboardStyle">@style/Keyboard.KLP</item>
         <item name="keyboardViewStyle">@style/KeyboardView.KLP</item>
         <item name="mainKeyboardViewStyle">@style/MainKeyboardView.KLP</item>
diff --git a/java/res/values/themes-lxx-dark.xml b/java/res/values/themes-lxx-dark.xml
index 67f94f3..b081772 100644
--- a/java/res/values/themes-lxx-dark.xml
+++ b/java/res/values/themes-lxx-dark.xml
@@ -20,6 +20,7 @@
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
     <style name="KeyboardTheme.LXX_Dark" parent="KeyboardIcons.LXX_Dark">
+        <item name="inputViewStyle">@style/InputView.LXX</item>
         <item name="keyboardStyle">@style/Keyboard.LXX_Dark</item>
         <item name="keyboardViewStyle">@style/KeyboardView.LXX_Dark</item>
         <item name="mainKeyboardViewStyle">@style/MainKeyboardView.LXX_Dark</item>
diff --git a/java/res/values/themes-lxx-light.xml b/java/res/values/themes-lxx-light.xml
index be817f4..3d294e4 100644
--- a/java/res/values/themes-lxx-light.xml
+++ b/java/res/values/themes-lxx-light.xml
@@ -20,6 +20,7 @@
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
     <style name="KeyboardTheme.LXX_Light" parent="KeyboardIcons.LXX_Light">
+        <item name="inputViewStyle">@style/InputView.LXX</item>
         <item name="keyboardStyle">@style/Keyboard.LXX_Light</item>
         <item name="keyboardViewStyle">@style/KeyboardView.LXX_Light</item>
         <item name="mainKeyboardViewStyle">@style/MainKeyboardView.LXX_Light</item>
diff --git a/java/res/values/themes-lxx.xml b/java/res/values/themes-lxx.xml
index c721888..463306b 100644
--- a/java/res/values/themes-lxx.xml
+++ b/java/res/values/themes-lxx.xml
@@ -19,6 +19,10 @@
 -->
 
 <resources xmlns:android="http://schemas.android.com/apk/res/android">
+    <style
+        name="InputView.LXX"
+        parent="InputView"
+    />
     <!-- LXX KeyboardView theme (LXX_Light and LXX_Dark) -->
     <style
         name="KeyboardView.LXX"
diff --git a/java/src/com/android/inputmethod/compat/ViewCompatUtils.java b/java/src/com/android/inputmethod/compat/ViewCompatUtils.java
index 0f00be1..16260ab 100644
--- a/java/src/com/android/inputmethod/compat/ViewCompatUtils.java
+++ b/java/src/com/android/inputmethod/compat/ViewCompatUtils.java
@@ -31,9 +31,6 @@
     private static final Method METHOD_setPaddingRelative = CompatUtils.getMethod(
             View.class, "setPaddingRelative",
             int.class, int.class, int.class, int.class);
-    // Note that View.setElevation(float) has been introduced in API level 21.
-    private static final Method METHOD_setElevation = CompatUtils.getMethod(
-            View.class, "setElevation", float.class);
     // Note that View.setTextAlignment(int) has been introduced in API level 17.
     private static final Method METHOD_setTextAlignment = CompatUtils.getMethod(
             View.class, "setTextAlignment", int.class);
@@ -58,10 +55,6 @@
         CompatUtils.invoke(view, null, METHOD_setPaddingRelative, start, top, end, bottom);
     }
 
-    public static void setElevation(final View view, final float elevation) {
-        CompatUtils.invoke(view, null, METHOD_setElevation, elevation);
-    }
-
     // These TEXT_ALIGNMENT_* constants have been introduced in API 17.
     public static final int TEXT_ALIGNMENT_INHERIT = 0;
     public static final int TEXT_ALIGNMENT_GRAVITY = 1;
diff --git a/java/src/com/android/inputmethod/compat/ViewOutlineProviderCompatUtils.java b/java/src/com/android/inputmethod/compat/ViewOutlineProviderCompatUtils.java
new file mode 100644
index 0000000..52b8b74
--- /dev/null
+++ b/java/src/com/android/inputmethod/compat/ViewOutlineProviderCompatUtils.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+package com.android.inputmethod.compat;
+
+import android.inputmethodservice.InputMethodService;
+import android.view.View;
+
+public class ViewOutlineProviderCompatUtils {
+    private ViewOutlineProviderCompatUtils() {
+        // This utility class is not publicly instantiable.
+    }
+
+    public interface InsetsUpdater {
+        public void setInsets(final InputMethodService.Insets insets);
+    }
+
+    private static final InsetsUpdater EMPTY_INSETS_UPDATER = new InsetsUpdater() {
+        @Override
+        public void setInsets(final InputMethodService.Insets insets) {}
+    };
+
+    public static InsetsUpdater setInsetsOutlineProvider(final View view) {
+        if (BuildCompatUtils.EFFECTIVE_SDK_INT < BuildCompatUtils.VERSION_CODES_LXX) {
+            return EMPTY_INSETS_UPDATER;
+        }
+        return ViewOutlineProviderCompatUtilsLXX.setInsetsOutlineProvider(view);
+    }
+}
diff --git a/java/src/com/android/inputmethod/compat/ViewOutlineProviderCompatUtilsLXX.java b/java/src/com/android/inputmethod/compat/ViewOutlineProviderCompatUtilsLXX.java
new file mode 100644
index 0000000..f9917ac
--- /dev/null
+++ b/java/src/com/android/inputmethod/compat/ViewOutlineProviderCompatUtilsLXX.java
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+package com.android.inputmethod.compat;
+
+import android.annotation.TargetApi;
+import android.graphics.Outline;
+import android.inputmethodservice.InputMethodService;
+import android.os.Build;
+import android.view.View;
+import android.view.ViewOutlineProvider;
+
+import com.android.inputmethod.compat.ViewOutlineProviderCompatUtils.InsetsUpdater;
+
+@TargetApi(Build.VERSION_CODES.L)
+class ViewOutlineProviderCompatUtilsLXX {
+    private ViewOutlineProviderCompatUtilsLXX() {
+        // This utility class is not publicly instantiable.
+    }
+
+    static InsetsUpdater setInsetsOutlineProvider(final View view) {
+        final InsetsOutlineProvider provider = new InsetsOutlineProvider(view);
+        view.setOutlineProvider(provider);
+        return provider;
+    }
+
+    private static class InsetsOutlineProvider extends ViewOutlineProvider
+            implements InsetsUpdater {
+        private final View mView;
+        private static final int NO_DATA = -1;
+        private int mLastVisibleTopInsets = NO_DATA;
+
+        public InsetsOutlineProvider(final View view) {
+            mView = view;
+            view.setOutlineProvider(this);
+        }
+
+        @Override
+        public void setInsets(final InputMethodService.Insets insets) {
+            final int visibleTopInsets = insets.visibleTopInsets;
+            if (mLastVisibleTopInsets != visibleTopInsets) {
+                mLastVisibleTopInsets = visibleTopInsets;
+                mView.invalidateOutline();
+            }
+        }
+
+        @Override
+        public void getOutline(final View view, final Outline outline) {
+            if (mLastVisibleTopInsets == NO_DATA) {
+                // Call default implementation.
+                ViewOutlineProvider.BACKGROUND.getOutline(view, outline);
+                return;
+            }
+            // TODO: Revisit this when floating/resize keyboard is supported.
+            outline.setRect(
+                    view.getLeft(), mLastVisibleTopInsets, view.getRight(), view.getBottom());
+        }
+    }
+}
diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index ec45462..4159585 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -60,6 +60,8 @@
 import com.android.inputmethod.annotations.UsedForTesting;
 import com.android.inputmethod.compat.CursorAnchorInfoCompatWrapper;
 import com.android.inputmethod.compat.InputMethodServiceCompatUtils;
+import com.android.inputmethod.compat.ViewOutlineProviderCompatUtils;
+import com.android.inputmethod.compat.ViewOutlineProviderCompatUtils.InsetsUpdater;
 import com.android.inputmethod.dictionarypack.DictionaryPackConstants;
 import com.android.inputmethod.event.Event;
 import com.android.inputmethod.event.HardwareEventDecoder;
@@ -154,6 +156,7 @@
 
     // TODO: Move these {@link View}s to {@link KeyboardSwitcher}.
     private View mInputView;
+    private InsetsUpdater mInsetsUpdater;
     private SuggestionStripView mSuggestionStripView;
     private TextView mExtractEditText;
 
@@ -754,6 +757,7 @@
     public void setInputView(final View view) {
         super.setInputView(view);
         mInputView = view;
+        mInsetsUpdater = ViewOutlineProviderCompatUtils.setInsetsOutlineProvider(view);
         updateSoftInputWindowLayoutParameters();
         mSuggestionStripView = (SuggestionStripView)view.findViewById(R.id.suggestion_strip_view);
         if (hasSuggestionStripView()) {
@@ -1191,6 +1195,7 @@
             // no visual element will be shown on the screen.
             outInsets.touchableInsets = inputHeight;
             outInsets.visibleTopInsets = inputHeight;
+            mInsetsUpdater.setInsets(outInsets);
             return;
         }
         final int suggestionsHeight = (!mKeyboardSwitcher.isShowingEmojiPalettes()
@@ -1211,6 +1216,7 @@
         }
         outInsets.contentTopInsets = visibleTopY;
         outInsets.visibleTopInsets = visibleTopY;
+        mInsetsUpdater.setInsets(outInsets);
     }
 
     public void startShowingInputView(final boolean needsToLoadKeyboard) {