SuggestionSpanUtils.java revision c61cd79229b1871d0f603a23389695d7f7751e66 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.inputmethod.compat;
18
19import com.android.inputmethod.latin.LatinImeLogger;
20import com.android.inputmethod.latin.SuggestedWords;
21import com.android.inputmethod.latin.SuggestionSpanPickedNotificationReceiver;
22
23import android.content.Context;
24import android.text.Spannable;
25import android.text.SpannableString;
26import android.text.Spanned;
27import android.text.TextUtils;
28import android.util.Log;
29
30import java.lang.reflect.Constructor;
31import java.lang.reflect.Field;
32import java.util.ArrayList;
33import java.util.Locale;
34
35public class SuggestionSpanUtils {
36    private static final String TAG = SuggestionSpanUtils.class.getSimpleName();
37    // TODO: Use reflection to get field values
38    public static final String ACTION_SUGGESTION_PICKED =
39            "android.text.style.SUGGESTION_PICKED";
40    public static final String SUGGESTION_SPAN_PICKED_AFTER = "after";
41    public static final String SUGGESTION_SPAN_PICKED_BEFORE = "before";
42    public static final String SUGGESTION_SPAN_PICKED_HASHCODE = "hashcode";
43    public static final boolean SUGGESTION_SPAN_IS_SUPPORTED;
44
45    private static final Class<?> CLASS_SuggestionSpan = CompatUtils
46            .getClass("android.text.style.SuggestionSpan");
47    private static final Class<?>[] INPUT_TYPE_SuggestionSpan = new Class<?>[] {
48            Context.class, Locale.class, String[].class, int.class, Class.class };
49    private static final Constructor<?> CONSTRUCTOR_SuggestionSpan = CompatUtils
50            .getConstructor(CLASS_SuggestionSpan, INPUT_TYPE_SuggestionSpan);
51    public static final Field FIELD_FLAG_EASY_CORRECT =
52            CompatUtils.getField(CLASS_SuggestionSpan, "FLAG_EASY_CORRECT");
53    public static final Field FIELD_FLAG_MISSPELLED =
54            CompatUtils.getField(CLASS_SuggestionSpan, "FLAG_MISSPELLED");
55    public static final Field FIELD_FLAG_AUTO_CORRECTION =
56            CompatUtils.getField(CLASS_SuggestionSpan, "FLAG_AUTO_CORRECTION");
57    public static final Field FIELD_SUGGESTIONS_MAX_SIZE
58            = CompatUtils.getField(CLASS_SuggestionSpan, "SUGGESTIONS_MAX_SIZE");
59    public static final Integer OBJ_FLAG_EASY_CORRECT = (Integer) CompatUtils
60            .getFieldValue(null, null, FIELD_FLAG_EASY_CORRECT);
61    public static final Integer OBJ_FLAG_MISSPELLED = (Integer) CompatUtils
62            .getFieldValue(null, null, FIELD_FLAG_MISSPELLED);
63    public static final Integer OBJ_FLAG_AUTO_CORRECTION = (Integer) CompatUtils
64            .getFieldValue(null, null, FIELD_FLAG_AUTO_CORRECTION);
65    public static final Integer OBJ_SUGGESTIONS_MAX_SIZE = (Integer) CompatUtils
66            .getFieldValue(null, null, FIELD_SUGGESTIONS_MAX_SIZE);
67
68    static {
69        SUGGESTION_SPAN_IS_SUPPORTED =
70                CLASS_SuggestionSpan != null && CONSTRUCTOR_SuggestionSpan != null;
71        if (LatinImeLogger.sDBG) {
72            if (SUGGESTION_SPAN_IS_SUPPORTED
73                    && (OBJ_FLAG_AUTO_CORRECTION == null || OBJ_SUGGESTIONS_MAX_SIZE == null
74                            || OBJ_FLAG_MISSPELLED == null || OBJ_FLAG_EASY_CORRECT == null)) {
75                throw new RuntimeException("Field is accidentially null.");
76            }
77        }
78    }
79
80    public static CharSequence getTextWithAutoCorrectionIndicatorUnderline(
81            Context context, CharSequence text) {
82        if (TextUtils.isEmpty(text) || CONSTRUCTOR_SuggestionSpan == null
83                || OBJ_FLAG_AUTO_CORRECTION == null || OBJ_SUGGESTIONS_MAX_SIZE == null
84                || OBJ_FLAG_MISSPELLED == null || OBJ_FLAG_EASY_CORRECT == null) {
85            return text;
86        }
87        final Spannable spannable = text instanceof Spannable
88                ? (Spannable) text : new SpannableString(text);
89        final Object[] args =
90                { context, null, new String[] {}, (int)OBJ_FLAG_AUTO_CORRECTION,
91                        (Class<?>) SuggestionSpanPickedNotificationReceiver.class };
92        final Object ss = CompatUtils.newInstance(CONSTRUCTOR_SuggestionSpan, args);
93        if (ss == null) {
94            Log.w(TAG, "Suggestion span was not created.");
95            return text;
96        }
97        spannable.setSpan(ss, 0, text.length(),
98                Spanned.SPAN_EXCLUSIVE_EXCLUSIVE | Spanned.SPAN_COMPOSING);
99        return spannable;
100    }
101
102    public static CharSequence getTextWithSuggestionSpan(Context context,
103            CharSequence pickedWord, SuggestedWords suggestedWords) {
104        if (TextUtils.isEmpty(pickedWord) || CONSTRUCTOR_SuggestionSpan == null
105                || suggestedWords == null || suggestedWords.size() == 0
106                || OBJ_SUGGESTIONS_MAX_SIZE == null) {
107            return pickedWord;
108        }
109
110        final Spannable spannable;
111        if (pickedWord instanceof Spannable) {
112            spannable = (Spannable) pickedWord;
113        } else {
114            spannable = new SpannableString(pickedWord);
115        }
116        final ArrayList<String> suggestionsList = new ArrayList<String>();
117        boolean sameAsTyped = false;
118        for (int i = 0; i < suggestedWords.size(); ++i) {
119            if (suggestionsList.size() >= OBJ_SUGGESTIONS_MAX_SIZE) {
120                break;
121            }
122            final CharSequence word = suggestedWords.getWord(i);
123            if (!TextUtils.equals(pickedWord, word)) {
124                suggestionsList.add(word.toString());
125            } else if (i == 0) {
126                sameAsTyped = true;
127            }
128        }
129        // TODO: Share the implementation for checking typed word validity between the IME
130        // and the spell checker.
131        final int flag = (sameAsTyped && !suggestedWords.mTypedWordValid)
132                ? (OBJ_FLAG_EASY_CORRECT | OBJ_FLAG_MISSPELLED)
133                : 0;
134
135        final Object[] args =
136                { context, null, suggestionsList.toArray(new String[suggestionsList.size()]), flag,
137                        (Class<?>) SuggestionSpanPickedNotificationReceiver.class };
138        final Object ss = CompatUtils.newInstance(CONSTRUCTOR_SuggestionSpan, args);
139        if (ss == null) {
140            return pickedWord;
141        }
142        spannable.setSpan(ss, 0, pickedWord.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
143        return spannable;
144    }
145}
146