Clarify the expected cursor position in RichInputConnection. (aa108f1d) · Commits · e / os / android_packages_inputmethods_LatinIME

java/src/com/android/inputmethod/latin/RichInputConnection.java

+29 −26

Original line number	Diff line number	Diff line
		@@ -56,11 +56,14 @@ public final class RichInputConnection {
		private static final int INVALID_CURSOR_POSITION = -1;

		/**
		* This variable contains the value LatinIME thinks the cursor position should be at now.
		* This is a few steps in advance of what the TextView thinks it is, because TextView will
		* only know after the IPC calls gets through.
		* This variable contains an expected value for the cursor position. This is where the
		* cursor may end up after all the keyboard-triggered updates have passed. We keep this to
		* compare it to the actual cursor position to guess whether the move was caused by a
		* keyboard command or not.
		* It's not really the cursor position: the cursor may not be there yet, and it's also expected
		* there be cases where it never actually comes to be there.
		*/
		private int mCurrentCursorPosition = INVALID_CURSOR_POSITION; // in chars, not code points
		private int mExpectedCursorPosition = INVALID_CURSOR_POSITION; // in chars, not code points
		/**
		* This contains the committed text immediately preceding the cursor and the composing
		* text if any. It is refreshed when the cursor moves by calling upon the TextView.
		@@ -101,16 +104,16 @@ public final class RichInputConnection {
		final String reference = (beforeCursor.length() <= actualLength) ? beforeCursor.toString()
		: beforeCursor.subSequence(beforeCursor.length() - actualLength,
		beforeCursor.length()).toString();
		if (et.selectionStart != mCurrentCursorPosition
		if (et.selectionStart != mExpectedCursorPosition
		\|\| !(reference.equals(internal.toString()))) {
		final String context = "Expected cursor position = " + mCurrentCursorPosition
		final String context = "Expected cursor position = " + mExpectedCursorPosition
		+ "\nActual cursor position = " + et.selectionStart
		+ "\nExpected text = " + internal.length() + " " + internal
		+ "\nActual text = " + reference.length() + " " + reference;
		((LatinIME)mParent).debugDumpStateAndCrashWithException(context);
		} else {
		Log.e(TAG, DebugLogUtils.getStackTrace(2));
		Log.e(TAG, "Exp <> Actual : " + mCurrentCursorPosition + " <> " + et.selectionStart);
		Log.e(TAG, "Exp <> Actual : " + mExpectedCursorPosition + " <> " + et.selectionStart);
		}
		}

		@@ -141,7 +144,7 @@ public final class RichInputConnection {

		public void resetCachesUponCursorMove(final int newCursorPosition,
		final boolean shouldFinishComposition) {
		mCurrentCursorPosition = newCursorPosition;
		mExpectedCursorPosition = newCursorPosition;
		mComposingText.setLength(0);
		mCommittedTextBeforeComposingText.setLength(0);
		final CharSequence textBeforeCursor = getTextBeforeCursor(DEFAULT_TEXT_CACHE_SIZE, 0);
		@@ -166,7 +169,7 @@ public final class RichInputConnection {
		if (DEBUG_BATCH_NESTING) checkBatchEdit();
		if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
		mCommittedTextBeforeComposingText.append(mComposingText);
		mCurrentCursorPosition += mComposingText.length();
		mExpectedCursorPosition += mComposingText.length();
		mComposingText.setLength(0);
		if (null != mIC) {
		mIC.finishComposingText();
		@@ -180,7 +183,7 @@ public final class RichInputConnection {
		if (DEBUG_BATCH_NESTING) checkBatchEdit();
		if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
		mCommittedTextBeforeComposingText.append(text);
		mCurrentCursorPosition += text.length() - mComposingText.length();
		mExpectedCursorPosition += text.length() - mComposingText.length();
		mComposingText.setLength(0);
		if (null != mIC) {
		mIC.commitText(text, i);
		@@ -193,7 +196,7 @@ public final class RichInputConnection {
		}

		public boolean canDeleteCharacters() {
		return mCurrentCursorPosition > 0;
		return mExpectedCursorPosition > 0;
		}

		/**
		@@ -230,7 +233,7 @@ public final class RichInputConnection {
		// heavy pressing of delete, for example DEFAULT_TEXT_CACHE_SIZE - 5 times or so.
		// getCapsMode should be updated to be able to return a "not enough info" result so that
		// we can get more context only when needed.
		if (TextUtils.isEmpty(mCommittedTextBeforeComposingText) && 0 != mCurrentCursorPosition) {
		if (TextUtils.isEmpty(mCommittedTextBeforeComposingText) && 0 != mExpectedCursorPosition) {
		mCommittedTextBeforeComposingText.append(
		getTextBeforeCursor(DEFAULT_TEXT_CACHE_SIZE, 0));
		}
		@@ -251,7 +254,7 @@ public final class RichInputConnection {
		mCommittedTextBeforeComposingText.length() + mComposingText.length();
		// If we have enough characters to satisfy the request, or if we have all characters in
		// the text field, then we can return the cached version right away.
		if (cachedLength >= n \|\| cachedLength >= mCurrentCursorPosition) {
		if (cachedLength >= n \|\| cachedLength >= mExpectedCursorPosition) {
		final StringBuilder s = new StringBuilder(mCommittedTextBeforeComposingText);
		s.append(mComposingText);
		if (s.length() > n) {
		@@ -284,10 +287,10 @@ public final class RichInputConnection {
		+ remainingChars, 0);
		mCommittedTextBeforeComposingText.setLength(len);
		}
		if (mCurrentCursorPosition > beforeLength) {
		mCurrentCursorPosition -= beforeLength;
		if (mExpectedCursorPosition > beforeLength) {
		mExpectedCursorPosition -= beforeLength;
		} else {
		mCurrentCursorPosition = 0;
		mExpectedCursorPosition = 0;
		}
		if (null != mIC) {
		mIC.deleteSurroundingText(beforeLength, afterLength);
		@@ -321,7 +324,7 @@ public final class RichInputConnection {
		switch (keyEvent.getKeyCode()) {
		case KeyEvent.KEYCODE_ENTER:
		mCommittedTextBeforeComposingText.append("\n");
		mCurrentCursorPosition += 1;
		mExpectedCursorPosition += 1;
		break;
		case KeyEvent.KEYCODE_DEL:
		if (0 == mComposingText.length()) {
		@@ -333,18 +336,18 @@ public final class RichInputConnection {
		} else {
		mComposingText.delete(mComposingText.length() - 1, mComposingText.length());
		}
		if (mCurrentCursorPosition > 0) mCurrentCursorPosition -= 1;
		if (mExpectedCursorPosition > 0) mExpectedCursorPosition -= 1;
		break;
		case KeyEvent.KEYCODE_UNKNOWN:
		if (null != keyEvent.getCharacters()) {
		mCommittedTextBeforeComposingText.append(keyEvent.getCharacters());
		mCurrentCursorPosition += keyEvent.getCharacters().length();
		mExpectedCursorPosition += keyEvent.getCharacters().length();
		}
		break;
		default:
		final String text = new String(new int[] { keyEvent.getUnicodeChar() }, 0, 1);
		mCommittedTextBeforeComposingText.append(text);
		mCurrentCursorPosition += text.length();
		mExpectedCursorPosition += text.length();
		break;
		}
		}
		@@ -378,7 +381,7 @@ public final class RichInputConnection {
		public void setComposingText(final CharSequence text, final int newCursorPosition) {
		if (DEBUG_BATCH_NESTING) checkBatchEdit();
		if (DEBUG_PREVIOUS_TEXT) checkConsistencyForDebug();
		mCurrentCursorPosition += text.length() - mComposingText.length();
		mExpectedCursorPosition += text.length() - mComposingText.length();
		mComposingText.setLength(0);
		mComposingText.append(text);
		// TODO: support values of i != 1. At this time, this is never called with i != 1.
		@@ -400,7 +403,7 @@ public final class RichInputConnection {
		ResearchLogger.richInputConnection_setSelection(start, end);
		}
		}
		mCurrentCursorPosition = start;
		mExpectedCursorPosition = start;
		mCommittedTextBeforeComposingText.setLength(0);
		mCommittedTextBeforeComposingText.append(getTextBeforeCursor(DEFAULT_TEXT_CACHE_SIZE, 0));
		}
		@@ -423,7 +426,7 @@ public final class RichInputConnection {
		// text should never be null, but just in case, it's better to insert nothing than to crash
		if (null == text) text = "";
		mCommittedTextBeforeComposingText.append(text);
		mCurrentCursorPosition += text.length() - mComposingText.length();
		mExpectedCursorPosition += text.length() - mComposingText.length();
		mComposingText.setLength(0);
		if (null != mIC) {
		mIC.commitCompletion(completionInfo);
		@@ -705,14 +708,14 @@ public final class RichInputConnection {
		*/
		public boolean isBelatedExpectedUpdate(final int oldSelStart, final int newSelStart) {
		// If this is an update that arrives at our expected position, it's a belated update.
		if (newSelStart == mCurrentCursorPosition) return true;
		if (newSelStart == mExpectedCursorPosition) return true;
		// If this is an update that moves the cursor from our expected position, it must be
		// an explicit move.
		if (oldSelStart == mCurrentCursorPosition) return false;
		if (oldSelStart == mExpectedCursorPosition) return false;
		// The following returns true if newSelStart is between oldSelStart and
		// mCurrentCursorPosition. We assume that if the updated position is between the old
		// position and the expected position, then it must be a belated update.
		return (newSelStart - oldSelStart) * (mCurrentCursorPosition - newSelStart) >= 0;
		return (newSelStart - oldSelStart) * (mExpectedCursorPosition - newSelStart) >= 0;
		}

		/**