1 /*
2  * Copyright (C) 2006 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 
17 package android.text.style;
18 
19 import android.annotation.NonNull;
20 import android.os.Parcel;
21 import android.text.ParcelableSpan;
22 import android.text.TextPaint;
23 import android.text.TextUtils;
24 
25 /**
26  * The span that moves the position of the text baseline lower.
27  * <p>
28  * The span can be used like this:
29  * <pre>{@code
30  *  SpannableString string = new SpannableString("☕- C8H10N4O2\n");
31  *string.setSpan(new SubscriptSpan(), 4, 5, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
32  *string.setSpan(new SubscriptSpan(), 6, 8, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
33  *string.setSpan(new SubscriptSpan(), 9, 10, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
34  *string.setSpan(new SubscriptSpan(), 11, 12, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);}</pre>
35  * <img src="{@docRoot}reference/android/images/text/style/subscriptspan.png" />
36  * <figcaption>Text with <code>SubscriptSpan</code>.</figcaption>
37  * Note: Since the span affects the position of the text, if the text is on the last line of a
38  * TextView, it may appear cut.
39  */
40 public class SubscriptSpan extends MetricAffectingSpan implements ParcelableSpan {
41 
42     /**
43      * Creates a {@link SubscriptSpan}.
44      */
SubscriptSpan()45     public SubscriptSpan() {
46     }
47 
48     /**
49      * Creates a {@link SubscriptSpan} from a parcel.
50      */
SubscriptSpan(@onNull Parcel src)51     public SubscriptSpan(@NonNull Parcel src) {
52     }
53 
54     @Override
getSpanTypeId()55     public int getSpanTypeId() {
56         return getSpanTypeIdInternal();
57     }
58 
59     /** @hide */
60     @Override
getSpanTypeIdInternal()61     public int getSpanTypeIdInternal() {
62         return TextUtils.SUBSCRIPT_SPAN;
63     }
64 
65     @Override
describeContents()66     public int describeContents() {
67         return 0;
68     }
69 
70     @Override
writeToParcel(Parcel dest, int flags)71     public void writeToParcel(Parcel dest, int flags) {
72         writeToParcelInternal(dest, flags);
73     }
74 
75     /** @hide */
76     @Override
writeToParcelInternal(Parcel dest, int flags)77     public void writeToParcelInternal(Parcel dest, int flags) {
78     }
79 
80     @Override
updateDrawState(@onNull TextPaint textPaint)81     public void updateDrawState(@NonNull TextPaint textPaint) {
82         textPaint.baselineShift -= (int) (textPaint.ascent() / 2);
83     }
84 
85     @Override
updateMeasureState(@onNull TextPaint textPaint)86     public void updateMeasureState(@NonNull TextPaint textPaint) {
87         textPaint.baselineShift -= (int) (textPaint.ascent() / 2);
88     }
89 
90     @Override
toString()91     public String toString() {
92         return "SubscriptSpan{}";
93     }
94 }
95