Support InputMethodManager#updateCursorAnchorInfo for Android 5.0

content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java

Index: content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java b/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
index e075d8e4d400dbef2f502c3f262b3455eed249a6..9a596088a15e4fabb2104f9857870955cfdec081 100644
--- a/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
+++ b/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
@@ -4,6 +4,9 @@
 
 package org.chromium.content.browser.input;
 
+import android.annotation.TargetApi;
+import android.graphics.Matrix;
+import android.os.Build;
 import android.os.Handler;
 import android.os.ResultReceiver;
 import android.os.SystemClock;
@@ -15,14 +18,22 @@ import android.text.style.UnderlineSpan;
 import android.view.KeyCharacterMap;
 import android.view.KeyEvent;
 import android.view.View;
+import android.view.inputmethod.CursorAnchorInfo;
 import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputConnection;
+import android.view.inputmethod.InputMethodManager;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 import org.chromium.base.VisibleForTesting;
+import org.chromium.cc.SelectionBoundType;
 import org.chromium.ui.picker.InputDialogContainer;
 
 import java.lang.CharSequence;
+import java.util.Arrays;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 
 /**
  * Adapts and plumbs android IME service onto the chrome text input API.
@@ -143,6 +154,302 @@ public class ImeAdapter {
     private int mTextInputFlags;
     private String mLastComposeText;
 
+    /**
+     * Minimum data set that is required to construct {@link CursorAnchorInfo} object.

[jdduke (slow), 2014/11/12 19:05:06]

This is a non-trivial code addition, would it make sense to pull it into a
separate class and get some isolated tests?

[yukawa, 2014/12/05 07:42:19]

Sounds reasonable.  Now the logic here is completely moved to native side as
ui/base/ime/android/cursor_anchor_info_controller.* with tests.

+     */
+    private static final class CursorAnchorInfoSource {
+        /**
+         * Special sequence ID that is never returned from {@link #getSequenceNo()}.
+         */
+        public static int INVALID_SEQUENCE_NO = 0;
+
+        private boolean mHasFrameInfo = false;
+        private String mText;
+        private int mSelectionStart;
+        private int mSelectionEnd;
+        private int mCompositionStart;
+        private int mCompositionEnd;
+        private float[] mCompositionCharacterBounds;
+        private boolean mHasInsertionMarker;
+        private float mInsertionMarkerHorizontal;
+        private float mInsertionMarkerTop;
+        private float mInsertionMarkerBottom;
+        private float mScale;
+        private float mTranslationX;
+        private float mTranslationY;
+        private int mSequenceNo = INVALID_SEQUENCE_NO + 1;
+
+
+        /**
+         * Resets the internal state.
+         */
+        public void reset() {
+            mHasFrameInfo = false;
+            mText = null;
+            mSelectionStart = -1;
+            mSelectionEnd = -1;
+            mCompositionStart = -1;
+            mCompositionEnd = -1;
+            mCompositionCharacterBounds = null;
+            mHasInsertionMarker = false;
+            mInsertionMarkerHorizontal = Float.NaN;
+            mInsertionMarkerTop = Float.NaN;
+            mInsertionMarkerBottom = Float.NaN;
+            mScale = 1.0f;
+            mTranslationX = 0.0f;
+            mTranslationY = 0.0f;
+        }
+
+        /**
+         * @return {@code true} if
+         * {@link #setFrameInfo(float, float, float, int, float, float, float)} was called after
+         * the object was instantiated or reinitialized by {@link #reset()}.
+         */

[jdduke (slow), 2015/01/21 19:16:42]

Do these accessors need public visibility? Where are they used? Can we get rid
of them?

+        public boolean hasFrameInfo() {
+            return mHasFrameInfo;
+        }
+
+        /**
+         * @return Current composing text (if any). {@code null}.
+         */
+        @Nullable
+        public CharSequence getComposingText() {
+            if (mText == null) {
+                return null;
+            }
+            if (0 <= mCompositionStart && mCompositionStart <= mText.length()) {
+                return mText.subSequence(mCompositionStart, mCompositionEnd);
+            }
+            return "";
+        }
+
+        /**
+         * @return Selection start index (inclusive) that was specified in
+         * {@link #setTextAndSelection(String, int, int, int, int)}.
+         */
+        public int getSelectionStart() {
+            return mSelectionStart;
+        }
+
+        /**
+         * @return Selection end index (exclusive) that was specified in
+         * {@link #setTextAndSelection(String, int, int, int, int)}.
+         */
+        public int getSelectionEnd() {
+            return mSelectionEnd;
+        }
+
+        /**
+         * @return Composing text start index (inclusive) that was specified in
+         * {@link #setTextAndSelection(String, int, int, int, int)}.
+         */
+        public int getCompositionStart() {
+            return mCompositionStart;
+        }
+
+        /**
+         * @return Array of local coordinates for each character bounds in the composing text.
+         */
+        @Nullable
+        public float[] getCompositionCharacterBounds() {
+            return mCompositionCharacterBounds;
+        }
+
+        /**
+         * @return {@code true} if an insertion marker is displayed.
+         */
+        public boolean hasInsertionMarker() {
+            return mHasInsertionMarker;
+        }
+
+        /**
+         * @return Horizontal position of the text insertion marker, in local coordinates.
+         */
+        public float getInsertionMarkerHorizontal() {
+            return mInsertionMarkerHorizontal;
+        }
+
+        /**
+         * @return Top position of the text insertion marker, in local coordinates.
+         */
+        public float getInsertionMarkerTop() {
+            return mInsertionMarkerTop;
+        }
+
+        /**
+         * @return Bottom position of the text insertion marker, in local coordinates.
+         */
+        public float getInsertionMarkerBottom() {
+            return mInsertionMarkerBottom;
+        }
+
+        /**
+         * @return Scaling factor from CSS (document) coordinates to Physical (screen) coordinates.
+         */
+        public float getScale() {
+            return mScale;
+        }
+
+        /**
+         * @return Horizontal offset from CSS (document) coordinates to View-local Physical (screen)
+         * coordinates. To obtain the display coordinates, add an offset returned from
+         * {@link View#getLocationOnScreen(int[])}.
+         */
+        public float getTranslationX() {
+            return mTranslationX;
+        }
+
+        /**
+         * @return Vertical offset from CSS (document) coordinates to View-local Physical (screen)
+         * coordinates. To obtain the display coordinates, add an offset returned from
+         * {@link View#getLocationOnScreen(int[])}.
+         */
+        public float getTranslationY() {
+            return mTranslationY;
+        }
+
+        /**
+         * @return The sequence number that will be updated when any of the fields is changed.
+         * Never returns {@link #INVALID_SEQUENCE_NO}.
+         */
+        public int getSequenceNo() {
+            return mSequenceNo;
+        }
+
+        private void incrementSequenceNo() {
+            ++mSequenceNo;
+            if (mSequenceNo == INVALID_SEQUENCE_NO) {
+                ++mSequenceNo;
+            }
+        }
+
+        /**
+         * Sets positional information of composing text as an array of character bounds.
+         * @param compositionCharacterBounds Array of character bounds in local coordinates.
+         */
+        public void setCompositionCharacterBounds(float[] compositionCharacterBounds) {
+            if (!Arrays.equals(compositionCharacterBounds, mCompositionCharacterBounds)) {
+                incrementSequenceNo();
+            }
+            mCompositionCharacterBounds = compositionCharacterBounds;
+        }
+
+        /**
+         * Sets text in the focused text area, selection range, and the composing text range.
+         * @param text Text in the focused text field.
+         * @param selectionStart Index where the text selection starts. {@code -1} if there is no
+         * selection.
+         * @param selectionEnd Index where the text selection ends. {@code -1} if there is no
+         * selection.
+         * @param compositionStart Index where the text composition starts. {@code -1} if there is
+         * no selection.
+         * @param compositionEnd Index where the text composition ends. {@code -1} if there is no
+         * selection.
+         */
+        public void setTextAndSelection(String text, int selectionStart, int selectionEnd,
+                int compositionStart, int compositionEnd) {
+            if (text != mText || selectionStart != mSelectionStart || selectionEnd != mSelectionEnd
+                    || compositionStart != mCompositionStart || compositionEnd != mCompositionEnd) {
+                incrementSequenceNo();
+            }
+            mText = text;
+            mSelectionStart = selectionStart;
+            mSelectionEnd = selectionEnd;
+            mCompositionStart = compositionStart;
+            mCompositionEnd = compositionEnd;
+        }
+
+        /**
+         * Sets coordinates system parameters and selection marker information.
+         * @param scale Scaling factor from CSS (document) coordinates to Physical (screen)
+         * coordinates.
+         * @param translationX Horizontal offset from CSS (document) coordinates to
+         * View-local Physical (screen) coordinates.
+         * @param translationY Vertical offset from CSS (document) coordinates to View-local
+         * Physical (screen) coordinates.
+         * @param frameMetadataSelectionStartType Type code that is defined in
+         * {@link SelectionBoundType}
+         * @param frameMetadataSelectionStartEdgeTopX X coordinate of the top of the first selection
+         * marker.
+         * @param frameMetadataSelectionStartEdgeTopY Y coordinate of the top of the first selection
+         * marker.
+         * @param frameMetadataSelectionStartEdgeBottomY Y coordinate of the bottom of the first
+         * selection marker.
+         */
+        public void setFrameInfo(float scale, float translationX, float translationY,
+                int frameMetadataSelectionStartType, float frameMetadataSelectionStartEdgeTopX,
+                float frameMetadataSelectionStartEdgeTopY,
+                float frameMetadataSelectionStartEdgeBottomY) {
+            // We are interested only in zero width selection bounds here because non-zero width
+            // selection bounds cannot be represented in CursorAnchorInfo API in Android Framework
+            // as of API Level 21. Actually supporting non-zero width selection bounds in
+            // CursorAnchorInfo API was once considered in the design phase of that API, but the
+            // idea was abandoned because the IME is still able to retrieve the same information
+            // from the following parameters in
+            // CursorAnchorInfo:
+            // - CursorAnchorInfo#getCharacterBounds and
+            // - CursorAnchorInfo#getSelection{Start, End}.
+            final boolean hasInsertionMarker =
+                    frameMetadataSelectionStartType == SelectionBoundType.SELECTION_BOUND_CENTER;
+            if (scale != mScale || translationX != mTranslationX || translationY != mTranslationY) {
+                incrementSequenceNo();
+            } else if (hasInsertionMarker) {
+                if (!mHasInsertionMarker
+                        || frameMetadataSelectionStartEdgeTopX != mInsertionMarkerHorizontal
+                        || frameMetadataSelectionStartEdgeTopY != mInsertionMarkerTop
+                        || frameMetadataSelectionStartEdgeBottomY != mInsertionMarkerBottom) {
+                    incrementSequenceNo();
+                }
+            } else if (mHasInsertionMarker) {
+                incrementSequenceNo();
+            }
+            mHasInsertionMarker = hasInsertionMarker;
+            if (mHasInsertionMarker) {
+                mInsertionMarkerHorizontal = frameMetadataSelectionStartEdgeTopX;
+                mInsertionMarkerTop = frameMetadataSelectionStartEdgeTopY;
+                mInsertionMarkerBottom = frameMetadataSelectionStartEdgeBottomY;
+            }
+            mScale = scale;
+            mTranslationX = translationX;
+            mTranslationY = translationY;
+            mHasFrameInfo = true;
+        }
+    }
+    private CursorAnchorInfoSource mCursorAnchorInfoSource = new CursorAnchorInfoSource();
+
+    private static class CursorAnchorInfoBuilderWrapper {
+
+        public static boolean isSupported() {
+            return false;
+        }
+
+        public static CursorAnchorInfoBuilderWrapper create() {
+            return new CursorAnchorInfoBuilderWrapper();
+        }
+
+        protected CursorAnchorInfoBuilderWrapper() {
+        }
+
+        /**
+         * Calls {@link InputConnection#updateCursorAnchorInfo(View, CursorAnchorInfo)} iff the API
+         * is available and the current IME actually requested it.
+         * @param inputMethodManagerWrapper Compatibility wrapper of {@link InputConnection}.
+         * @param source Data source from which {@link CursorAnchorInfo} is created.
+         * @param view {@link View} object that should be passed to
+         * {@link InputConnection#updateCursorAnchorInfo(View, CursorAnchorInfo)}.
+         */
+        @SuppressWarnings("unused")
+        public void send(@Nonnull InputMethodManagerWrapper inputMethodManagerWrapper,

[jdduke (slow), 2015/01/21 19:16:41]

I don't quite understand this function?

+                @Nonnull CursorAnchorInfoSource source, @Nonnull View view) {
+            // This is a stub for platforms that do not support CursorAnchorInfo.
+        }
+    }
+
+    private final CursorAnchorInfoBuilderWrapper mCursorAnchorInfoBuilder =
+            CursorAnchorInfoBuilderWrapper.create();
+    private boolean mCursorAnchorInfoMonitorEnabled = false;
+    private boolean mOneshotUpdateCursorAnchorInfoEnabled = false;
+
     @VisibleForTesting
     int mLastSyntheticKeyCode;
 
@@ -621,6 +928,75 @@ public class ImeAdapter {
         return true;
     }
 
+    /**
+     * @return Whether the {@link CursorAnchorInfo} is available or not on this device.
+     */
+    public boolean isCursorAnchorInfoSupported() {
+        return CursorAnchorInfoBuilderWrapper.isSupported();
+    }
+
+    /**
+     * Start or stop calling
+     * {@link InputMethodManager#updateCursorAnchorInfo(View, CursorAnchorInfo)}.
+     * @param enabled {@code true} if {@link InputConnection#requestCursorUpdates(int)} is called
+     * with {@link InputConnection#CURSOR_UPDATE_MONITOR} bit.
+     */
+    public void setCursorAnchorInfoMonitorEnabled(boolean enabled) {
+        mCursorAnchorInfoMonitorEnabled = enabled;
+    }
+
+    /**
+     * Make sure {@link InputMethodManager#updateCursorAnchorInfo(View, CursorAnchorInfo)} is called
+     * at least once immediately when the latest position becomes available.
+     * @param view The view to be passed to
+     * {@link InputMethodManager#updateCursorAnchorInfo(View, CursorAnchorInfo)} if the latest
+     * position is already available. Otherwise ignored.
+     */
+    public void scheduleOneshotUpdateCursorAnchorInfo(View view) {
+        if (!mCursorAnchorInfoSource.hasFrameInfo()) {

[jdduke (slow), 2015/01/21 19:16:41]

Where is this method called?

+            // If there is no frame info, send the data later when it becomes available.
+            mOneshotUpdateCursorAnchorInfoEnabled = true;
+            return;
+        }
+        mCursorAnchorInfoBuilder.send(mInputMethodManagerWrapper, mCursorAnchorInfoSource,
+                mViewEmbedder.getAttachedView());
+        mOneshotUpdateCursorAnchorInfoEnabled = false;
+    }
+
+    /**
+     * Update the parameters that are to be passed to the IME through
+     * {@link InputMethodManager#updateCursorAnchorInfo(View, CursorAnchorInfo)}.
+     * @param text Text in the focused text field.
+     * @param selectionStart Index where the text selection starts. {@code -1} if there is no
+     * selection.
+     * @param selectionEnd Index where the text selection ends. {@code -1} if there is no
+     * selection.
+     * @param compositionStart Index where the text composition starts. {@code -1} if there is no
+     * selection.
+     * @param compositionEnd Index where the text composition ends. {@code -1} if there is no
+     * selection.
+     */
+    public void updateTextAndSelection(String text, int selectionStart, int selectionEnd,
+            int compositionStart, int compositionEnd) {
+        mCursorAnchorInfoSource.setTextAndSelection(text, selectionStart, selectionEnd,
+                compositionStart, compositionEnd);
+    }
+
+    public void onUpdateFrameInfo(float scale, float translationX, float translationY,
+            int frameMetadataSelectionStartType, float frameMetadataSelectionStartEdgeTopX,
+            float frameMetadataSelectionStartEdgeTopY,
+            float frameMetadataSelectionStartEdgeBottomY) {
+        mCursorAnchorInfoSource.setFrameInfo(scale, translationX, translationY,
+                frameMetadataSelectionStartType, frameMetadataSelectionStartEdgeTopX,
+                frameMetadataSelectionStartEdgeTopY, frameMetadataSelectionStartEdgeBottomY);
+        if (!mCursorAnchorInfoMonitorEnabled && !mOneshotUpdateCursorAnchorInfoEnabled) {
+            return;
+        }
+        mCursorAnchorInfoBuilder.send(mInputMethodManagerWrapper, mCursorAnchorInfoSource,
+                mViewEmbedder.getAttachedView());
+        mOneshotUpdateCursorAnchorInfoEnabled = false;
+    }
+
     // Calls from C++ to Java
 
     @CalledByNative
@@ -699,7 +1075,7 @@ public class ImeAdapter {
 
     @CalledByNative
     private void setCharacterBounds(float[] characterBounds) {
-        // TODO(yukawa): Implement this.
+        mCursorAnchorInfoSource.setCompositionCharacterBounds(characterBounds);
     }
 
     @CalledByNative
@@ -710,6 +1086,7 @@ public class ImeAdapter {
         }
         mNativeImeAdapterAndroid = 0;
         mTextInputType = 0;
+        mCursorAnchorInfoSource.reset();
     }
 
     private native boolean nativeSendSyntheticKeyEvent(long nativeImeAdapterAndroid,