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Diffstat (limited to 'src/com/android/browser/autocomplete/SuggestedTextController.java')
| -rw-r--r-- | src/com/android/browser/autocomplete/SuggestedTextController.java | 516 |
1 files changed, 0 insertions, 516 deletions
diff --git a/src/com/android/browser/autocomplete/SuggestedTextController.java b/src/com/android/browser/autocomplete/SuggestedTextController.java deleted file mode 100644 index 95dfcab..0000000 --- a/src/com/android/browser/autocomplete/SuggestedTextController.java +++ /dev/null @@ -1,516 +0,0 @@ -/* - * Copyright (C) 2010 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.browser.autocomplete; - -import com.google.common.annotations.VisibleForTesting; - -import android.os.Parcel; -import android.os.Parcelable; -import android.text.Editable; -import android.text.Selection; -import android.text.SpanWatcher; -import android.text.Spannable; -import android.text.Spanned; -import android.text.TextUtils; -import android.text.TextWatcher; -import android.util.Log; -import android.view.View; -import android.widget.EditText; - -import java.util.ArrayList; - -import junit.framework.Assert; - - -/** - * The query editor can show a suggestion, grayed out following the query that the user has - * entered so far. As the user types new characters, these should replace the grayed suggestion - * text. This class manages this logic, displaying the suggestion when the user entered text is a - * prefix of it, and hiding it otherwise. - * - * Note, the text in the text view will contain the entire suggestion, not just what the user - * entered. Instead of retrieving the text from the text view, {@link #getUserText()} should be - * called on this class. - */ -public class SuggestedTextController { - private static final boolean DBG = false; - private static final String TAG = "Browser.SuggestedTextController"; - - private final BufferTextWatcher mBufferTextWatcher = new BufferTextWatcher(); - private final BufferSpanWatcher mBufferSpanWatcher = new BufferSpanWatcher(); - private final ArrayList<TextChangeWatcher> mTextWatchers; - private final TextOwner mTextOwner; - private final StringBuffer mUserEntered; - private final SuggestedSpan mSuggested; - private String mSuggestedText; - private TextChangeAttributes mCurrentTextChange; - private boolean mSuspended = false; - - /** - * While this is non-null, any changes made to the cursor position or selection are ignored. Is - * stored the selection state at the moment when selection change processing was disabled. - */ - private BufferSelection mTextSelectionBeforeIgnoringChanges; - - public SuggestedTextController(final EditText textView, int color) { - this(new TextOwner() { - @Override - public Editable getText() { - return textView.getText(); - } - @Override - public void addTextChangedListener(TextWatcher watcher) { - textView.addTextChangedListener(watcher); - } - @Override - public void removeTextChangedListener(TextWatcher watcher) { - textView.removeTextChangedListener(watcher); - } - @Override - public void setText(String text) { - textView.setText(text); - } - }, color); - } - - private void initialize(String userText, int selStart, int selEnd, String suggested) { - Editable text = mTextOwner.getText(); - - if (userText == null) userText = ""; - String allText = userText; - int suggestedStart = allText.length(); - if (suggested != null && userText != null) { - if (suggested.startsWith(userText.toLowerCase())) { - allText = suggested; - } - } - - // allText is at this point either "userText" (not null) or - // "suggested" if thats not null and starts with userText. - text.replace(0, text.length(), allText); - Selection.setSelection(text, selStart, selEnd); - mUserEntered.replace(0, mUserEntered.length(), userText); - mSuggestedText = suggested; - if (suggestedStart < text.length()) { - text.setSpan(mSuggested, suggestedStart, text.length(), - Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); - } else { - text.removeSpan(mSuggested); - } - text.setSpan(mBufferSpanWatcher, 0, text.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE); - mTextOwner.addTextChangedListener(mBufferTextWatcher); - if (DBG) checkInvariant(text); - } - - private void assertNotIgnoringSelectionChanges() { - if (mTextSelectionBeforeIgnoringChanges != null) { - throw new IllegalStateException( - "Illegal operation while cursor movement processing suspended"); - } - } - - public boolean isCursorHandlingSuspended() { - return mSuspended; - } - - public Parcelable saveInstanceState(Parcelable superState) { - assertNotIgnoringSelectionChanges(); - SavedState ss = new SavedState(superState); - Editable buffer = mTextOwner.getText(); - ss.mUserText = getUserText(); - ss.mSuggestedText = mSuggestedText; - ss.mSelStart = Selection.getSelectionStart(buffer); - ss.mSelEnd = Selection.getSelectionEnd(buffer); - return ss; - } - - public Parcelable restoreInstanceState(Parcelable state) { - assertNotIgnoringSelectionChanges(); - if (!(state instanceof SavedState)) return state; - SavedState ss = (SavedState) state; - if (DBG) { - Log.d(TAG, "restoreInstanceState t='" + ss.mUserText + "' suggestion='" + - ss.mSuggestedText + " sel=" + ss.mSelStart + ".." + ss.mSelEnd); - } - // remove our listeners so we don't get notifications while re-initialising - mTextOwner.getText().removeSpan(mBufferSpanWatcher); - mTextOwner.removeTextChangedListener(mBufferTextWatcher); - // and initialise will re-add the watchers - initialize(ss.mUserText, ss.mSelStart, ss.mSelEnd, ss.mSuggestedText); - notifyUserEnteredChanged(); - return ss.getSuperState(); - } - - /** - * Temporarily stop processing cursor movements and selection changes. While cursor movements - * are being ignored, the text in the buffer must NOT be changed; doing so will result in an - * {@link IllegalStateException} being thrown. - * - * To stop ignoring cursor movements, call - * {@link #resumeCursorMovementHandlingAndApplyChanges()}. - */ - public void suspendCursorMovementHandling() { - assertNotIgnoringSelectionChanges(); - Editable buffer = mTextOwner.getText(); - mTextSelectionBeforeIgnoringChanges = new BufferSelection(buffer); - mSuspended = true; - } - - /** - * Start responding to cursor movements and selection changes again. If the cursor or selection - * moved while it was being ignored, these changes will be processed now. - */ - public void resumeCursorMovementHandlingAndApplyChanges() { - Editable buffer = mTextOwner.getText(); - BufferSelection oldSelection = mTextSelectionBeforeIgnoringChanges; - mTextSelectionBeforeIgnoringChanges = null; - BufferSelection newSelection = new BufferSelection(buffer); - if (oldSelection.mStart != newSelection.mStart) { - mBufferSpanWatcher.onSpanChanged(buffer, Selection.SELECTION_START, - oldSelection.mStart, oldSelection.mStart, - newSelection.mStart, newSelection.mStart); - } - if (oldSelection.mEnd != newSelection.mEnd) { - mBufferSpanWatcher.onSpanChanged(buffer, Selection.SELECTION_END, - oldSelection.mEnd, oldSelection.mEnd, - newSelection.mEnd, newSelection.mEnd); - } - mSuspended = false; - } - - /** - * Sets the current suggested text. A portion of this will be added to the user entered text if - * that is a prefix of the suggestion. - */ - public void setSuggestedText(String text) { - assertNotIgnoringSelectionChanges(); - if (!TextUtils.equals(text, mSuggestedText)) { - if (DBG) Log.d(TAG, "setSuggestedText(" + text + ")"); - mSuggestedText = text; - if (mCurrentTextChange == null) { - mCurrentTextChange = new TextChangeAttributes(0, 0, 0); - Editable buffer = mTextOwner.getText(); - handleTextChanged(buffer); - } - } - } - - /** - * Gets the portion of displayed text that is not suggested. - */ - public String getUserText() { - assertNotIgnoringSelectionChanges(); - return mUserEntered.toString(); - } - - /** - * Sets the given text as if it has been entered by the user. - */ - public void setText(String text) { - assertNotIgnoringSelectionChanges(); - if (text == null) text = ""; - Editable buffer = mTextOwner.getText(); - buffer.removeSpan(mSuggested); - // this will cause a handleTextChanged call - buffer.replace(0, text.length(), text); - } - - public void addUserTextChangeWatcher(TextChangeWatcher watcher) { - mTextWatchers.add(watcher); - } - - private void handleTextChanged(Editable newText) { - // When we make changes to the buffer from within this function, it results in recursive - // calls to beforeTextChanges(), afterTextChanged(). We want to ignore the changes we're - // making ourself: - if (mCurrentTextChange.isHandled()) return; - mCurrentTextChange.setHandled(); - final int pos = mCurrentTextChange.mPos; - final int countBefore = mCurrentTextChange.mCountBefore; - final int countAfter = mCurrentTextChange.mCountAfter; - final int cursorPos = Selection.getSelectionEnd(newText); - if (DBG) { - Log.d(TAG, "pos=" + pos +"; countBefore=" + countBefore + "; countAfter=" + - countAfter + "; cursor=" + cursorPos); - } - mUserEntered.replace(pos, pos + countBefore, - newText.subSequence(pos, pos + countAfter).toString()); - if (DBG) Log.d(TAG, "User entered: '" + mUserEntered + "' all='" + newText + "'"); - final int userLen = mUserEntered.length(); - boolean haveSuggested = newText.getSpanStart(mSuggested) != -1; - if (mSuggestedText != null && - mSuggestedText.startsWith(mUserEntered.toString().toLowerCase())) { - if (haveSuggested) { - if (!mSuggestedText.equalsIgnoreCase(newText.toString())) { - if (countAfter > countBefore) { - // net insertion - int len = countAfter - countBefore; - newText.delete(pos + len, pos + len + len); - } else { - // net deletion - newText.replace(userLen, newText.length(), - mSuggestedText.substring(userLen)); - if (countBefore == 0) { - // no change to the text - likely just suggested change - Selection.setSelection(newText, cursorPos); - } - } - } - } else { - // no current suggested text - add it - newText.insert(userLen, mSuggestedText.substring(userLen)); - // keep the cursor at the end of the user entered text, if that where it was - // before. - if (cursorPos == userLen) { - Selection.setSelection(newText, userLen); - } - } - if (userLen == newText.length()) { - newText.removeSpan(mSuggested); - } else { - newText.setSpan(mSuggested, userLen, newText.length(), - Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); - } - } else { - if (newText.getSpanStart(mSuggested) != -1) { - newText.removeSpan(mSuggested); - newText.delete(mUserEntered.length(), newText.length()); - } - } - if (DBG) checkInvariant(newText); - mCurrentTextChange = null; - if (countBefore > 0 || countAfter > 0) { - notifyUserEnteredChanged(); - } - } - - private void notifyUserEnteredChanged() { - for (TextChangeWatcher watcher : mTextWatchers) { - watcher.onTextChanged(mUserEntered.toString()); - } - } - - /** - * Basic interface for being notified of changes to some text. - */ - public interface TextChangeWatcher { - void onTextChanged(String newText); - } - - /** - * Interface class to wrap required methods from {@link EditText}, or some other class used - * to test without needing an @{link EditText}. - */ - public interface TextOwner { - Editable getText(); - void addTextChangedListener(TextWatcher watcher); - void removeTextChangedListener(TextWatcher watcher); - void setText(String text); - } - - /** - * This class stores the parameters passed to {@link BufferTextWatcher#beforeTextChanged}, - * together with a flag indicating if this invocation has been dealt with yet. We need this - * information, together with the parameters passed to - * {@link BufferTextWatcher#afterTextChanged}, to restore our internal state when the buffer is - * edited. - * - * Since the changes we make from within {@link BufferTextWatcher#afterTextChanged} also trigger - * further recursive calls to {@link BufferTextWatcher#beforeTextChanged} and - * {@link BufferTextWatcher#afterTextChanged}, this class helps detect these recursive calls so - * they can be ignored. - */ - private static class TextChangeAttributes { - public final int mPos; - public final int mCountAfter; - public final int mCountBefore; - private boolean mHandled; - - public TextChangeAttributes(int pos, int countAfter, int countBefore) { - mPos = pos; - mCountAfter = countAfter; - mCountBefore = countBefore; - } - - public void setHandled() { - mHandled = true; - } - - public boolean isHandled() { - return mHandled; - } - } - - /** - * Encapsulates the state of the text selection (and cursor) within a text buffer. - */ - private static class BufferSelection { - final int mStart; - final int mEnd; - public BufferSelection(CharSequence text) { - mStart = Selection.getSelectionStart(text); - mEnd = Selection.getSelectionEnd(text); - } - @Override - public boolean equals(Object other) { - if (!(other instanceof BufferSelection)) return super.equals(other); - BufferSelection otherSel = (BufferSelection) other; - return this.mStart == otherSel.mStart && this.mEnd == otherSel.mEnd; - } - } - - private class BufferTextWatcher implements TextWatcher { - @Override - public void afterTextChanged(Editable newText) { - if (DBG) { - Log.d(TAG, "afterTextChanged('" + newText + "')"); - } - assertNotIgnoringSelectionChanges(); - handleTextChanged(newText); - } - - @Override - public void beforeTextChanged(CharSequence s, int start, int count, int after) { - assertNotIgnoringSelectionChanges(); - if (mCurrentTextChange == null) { - mCurrentTextChange = new TextChangeAttributes(start, after, count); - } - } - - @Override - public void onTextChanged(CharSequence s, int start, int before, int count) { - } - } - - private class BufferSpanWatcher implements SpanWatcher { - @Override - public void onSpanAdded(Spannable text, Object what, int start, int end) { - } - - @Override - public void onSpanChanged( - Spannable text, Object what, int ostart, int oend, int nstart, int nend) { - if (mCurrentTextChange != null) return; - if (mTextSelectionBeforeIgnoringChanges != null) return; - if (what == Selection.SELECTION_END) { - if (DBG) Log.d(TAG, "cursor move to " + nend); - if (nend > mUserEntered.length()) { - mUserEntered.replace(0, mUserEntered.length(), text.toString()); - text.removeSpan(mSuggested); - } - if (DBG) checkInvariant(text); - } - } - - @Override - public void onSpanRemoved(Spannable text, Object what, int start, int end) { - } - } - - public static class SavedState extends View.BaseSavedState { - String mUserText; - String mSuggestedText; - int mSelStart; - int mSelEnd; - - public SavedState(Parcelable superState) { - super(superState); - } - - @Override - public void writeToParcel(Parcel out, int flags) { - super.writeToParcel(out, flags); - out.writeString(mUserText); - out.writeString(mSuggestedText); - out.writeInt(mSelStart); - out.writeInt(mSelEnd); - } - - @SuppressWarnings("hiding") - public static final Parcelable.Creator<SavedState> CREATOR - = new Parcelable.Creator<SavedState>() { - @Override - public SavedState createFromParcel(Parcel in) { - return new SavedState(in); - } - - @Override - public SavedState[] newArray(int size) { - return new SavedState[size]; - } - }; - - private SavedState(Parcel in) { - super(in); - mUserText = in.readString(); - mSuggestedText = in.readString(); - mSelStart = in.readInt(); - mSelEnd = in.readInt(); - } - } - - /* - * The remaining functions are used for testing purposes only. - * ----------------------------------------------------------- - */ - - /** - * Verify that the internal state of this class is consistent. - */ - @VisibleForTesting - void checkInvariant(final Spannable s) { - int suggestedStart = s.getSpanStart(mSuggested); - int suggestedEnd = s.getSpanEnd(mSuggested); - int cursorPos = Selection.getSelectionEnd(s); - if (suggestedStart == -1 || suggestedEnd == -1) { - suggestedStart = suggestedEnd = s.length(); - } - String userEntered = getUserText(); - Log.d(TAG, "checkInvariant all='" + s + "' (len " + s.length() + ") sug=" - + suggestedStart + ".." + suggestedEnd + " cursor=" + cursorPos + - " ue='" + userEntered + "' (len " + userEntered.length() + ")"); - int suggestedLen = suggestedEnd - suggestedStart; - Assert.assertEquals("Sum of user and suggested text lengths doesn't match total length", - s.length(), userEntered.length() + suggestedLen); - Assert.assertEquals("End of user entered text doesn't match start of suggested", - suggestedStart, userEntered.length()); - Assert.assertTrue("user entered text does not match start of buffer", - userEntered.toString().equalsIgnoreCase( - s.subSequence(0, suggestedStart).toString())); - if (mSuggestedText != null && suggestedStart < s.length()) { - Assert.assertTrue("User entered is not a prefix of suggested", - mSuggestedText.startsWith(userEntered.toString().toLowerCase())); - Assert.assertTrue("Suggested text does not match buffer contents", - mSuggestedText.equalsIgnoreCase(s.toString().toLowerCase())); - } - if (mSuggestedText == null) { - Assert.assertEquals("Non-zero suggention length with null suggestion", 0, suggestedLen); - } else { - Assert.assertTrue("Suggestion text longer than suggestion (" + mSuggestedText.length() + - ">" + suggestedLen + ")", suggestedLen <= mSuggestedText.length()); - } - Assert.assertTrue("Cursor within suggested part", cursorPos <= suggestedStart); - } - - @VisibleForTesting - SuggestedTextController(TextOwner textOwner, int color) { - mUserEntered = new StringBuffer(); - mSuggested = new SuggestedSpan(color); - mTextOwner = textOwner; - mTextWatchers = new ArrayList<TextChangeWatcher>(); - initialize(null, 0, 0, null); - } -} |