1 /*
2  * Copyright (C) 2018 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.graphics.fonts;
18 
19 import android.annotation.IntDef;
20 import android.annotation.IntRange;
21 import android.annotation.NonNull;
22 import android.annotation.Nullable;
23 
24 import com.android.internal.util.Preconditions;
25 
26 import java.lang.annotation.Retention;
27 import java.lang.annotation.RetentionPolicy;
28 import java.util.Objects;
29 
30 /**
31  * A font style object.
32  *
33  * This class represents a single font style which is a pair of weight value and slant value.
34  * Here are common font styles examples:
35  * <p>
36  * <pre>
37  * <code>
38  * final FontStyle NORMAL = new FontStyle(FONT_WEIGHT_NORMAL, FONT_SLANT_UPRIGHT);
39  * final FontStyle BOLD = new FontStyle(FONT_WEIGHT_BOLD, FONT_SLANT_UPRIGHT);
40  * final FontStyle ITALIC = new FontStyle(FONT_WEIGHT_NORMAL, FONT_SLANT_ITALIC);
41  * final FontStyle BOLD_ITALIC = new FontStyle(FONT_WEIGHT_BOLD, FONT_SLANT_ITALIC);
42  * </code>
43  * </pre>
44  * </p>
45  *
46  */
47 public final class FontStyle {
48     private static final String TAG = "FontStyle";
49 
50     /**
51      * A minimum weight value for the font
52      */
53     public static final int FONT_WEIGHT_MIN = 1;
54 
55     /**
56      * A font weight value for the thin weight
57      */
58     public static final int FONT_WEIGHT_THIN = 100;
59 
60     /**
61      * A font weight value for the extra-light weight
62      */
63     public static final int FONT_WEIGHT_EXTRA_LIGHT = 200;
64 
65     /**
66      * A font weight value for the light weight
67      */
68     public static final int FONT_WEIGHT_LIGHT = 300;
69 
70     /**
71      * A font weight value for the normal weight
72      */
73     public static final int FONT_WEIGHT_NORMAL = 400;
74 
75     /**
76      * A font weight value for the medium weight
77      */
78     public static final int FONT_WEIGHT_MEDIUM = 500;
79 
80     /**
81      * A font weight value for the semi-bold weight
82      */
83     public static final int FONT_WEIGHT_SEMI_BOLD = 600;
84 
85     /**
86      * A font weight value for the bold weight.
87      */
88     public static final int FONT_WEIGHT_BOLD = 700;
89 
90     /**
91      * A font weight value for the extra-bold weight
92      */
93     public static final int FONT_WEIGHT_EXTRA_BOLD = 800;
94 
95     /**
96      * A font weight value for the black weight
97      */
98     public static final int FONT_WEIGHT_BLACK = 900;
99 
100     /**
101      * A maximum weight value for the font
102      */
103     public static final int FONT_WEIGHT_MAX = 1000;
104 
105     /**
106      * A font slant value for upright
107      */
108     public static final int FONT_SLANT_UPRIGHT = 0;
109 
110     /**
111      * A font slant value for italic
112      */
113     public static final int FONT_SLANT_ITALIC = 1;
114 
115     // TODO: Support FONT_SLANT_OBLIQUE
116 
117     /** @hide */
118     @IntDef(prefix = { "FONT_SLANT_" }, value = {
119             FONT_SLANT_UPRIGHT,
120             FONT_SLANT_ITALIC
121     })
122     @Retention(RetentionPolicy.SOURCE)
123     public @interface FontSlant {}
124 
125     private final @IntRange(from = 0, to = 1000) int mWeight;
126     private final @FontSlant int mSlant;
127     // TODO: Support width
128 
FontStyle()129     public FontStyle() {
130         mWeight = FONT_WEIGHT_NORMAL;
131         mSlant = FONT_SLANT_UPRIGHT;
132     }
133 
134     /**
135      * Create FontStyle with specific weight and italic
136      *
137      * <p>
138      *  <table>
139      *  <thead>
140      *  <tr>
141      *  <th align="center">Value</th>
142      *  <th align="center">Name</th>
143      *  <th align="center">Android Definition</th>
144      *  </tr>
145      *  </thead>
146      *  <tbody>
147      *  <tr>
148      *  <td align="center">100</td>
149      *  <td align="center">Thin</td>
150      *  <td align="center">{@link FontStyle#FONT_WEIGHT_THIN}</td>
151      *  </tr>
152      *  <tr>
153      *  <td align="center">200</td>
154      *  <td align="center">Extra Light (Ultra Light)</td>
155      *  <td align="center">{@link FontStyle#FONT_WEIGHT_EXTRA_LIGHT}</td>
156      *  </tr>
157      *  <tr>
158      *  <td align="center">300</td>
159      *  <td align="center">Light</td>
160      *  <td align="center">{@link FontStyle#FONT_WEIGHT_LIGHT}</td>
161      *  </tr>
162      *  <tr>
163      *  <td align="center">400</td>
164      *  <td align="center">Normal (Regular)</td>
165      *  <td align="center">{@link FontStyle#FONT_WEIGHT_NORMAL}</td>
166      *  </tr>
167      *  <tr>
168      *  <td align="center">500</td>
169      *  <td align="center">Medium</td>
170      *  <td align="center">{@link FontStyle#FONT_WEIGHT_MEDIUM}</td>
171      *  </tr>
172      *  <tr>
173      *  <td align="center">600</td>
174      *  <td align="center">Semi Bold (Demi Bold)</td>
175      *  <td align="center">{@link FontStyle#FONT_WEIGHT_SEMI_BOLD}</td>
176      *  </tr>
177      *  <tr>
178      *  <td align="center">700</td>
179      *  <td align="center">Bold</td>
180      *  <td align="center">{@link FontStyle#FONT_WEIGHT_BOLD}</td>
181      *  </tr>
182      *  <tr>
183      *  <td align="center">800</td>
184      *  <td align="center">Extra Bold (Ultra Bold)</td>
185      *  <td align="center">{@link FontStyle#FONT_WEIGHT_EXTRA_BOLD}</td>
186      *  </tr>
187      *  <tr>
188      *  <td align="center">900</td>
189      *  <td align="center">Black (Heavy)</td>
190      *  <td align="center">{@link FontStyle#FONT_WEIGHT_BLACK}</td>
191      *  </tr>
192      *  </tbody>
193      * </p>
194      *
195      * @see FontStyle#FONT_WEIGHT_THIN
196      * @see FontStyle#FONT_WEIGHT_EXTRA_LIGHT
197      * @see FontStyle#FONT_WEIGHT_LIGHT
198      * @see FontStyle#FONT_WEIGHT_NORMAL
199      * @see FontStyle#FONT_WEIGHT_MEDIUM
200      * @see FontStyle#FONT_WEIGHT_SEMI_BOLD
201      * @see FontStyle#FONT_WEIGHT_BOLD
202      * @see FontStyle#FONT_WEIGHT_EXTRA_BOLD
203      * @see FontStyle#FONT_WEIGHT_BLACK
204      * @param weight a weight value
205      * @param slant a slant value
206      */
FontStyle(int weight, @FontSlant int slant)207     public FontStyle(int weight, @FontSlant int slant) {
208         Preconditions.checkArgument(FONT_WEIGHT_MIN <= weight && weight <= FONT_WEIGHT_MAX,
209                 "weight value must be [" + FONT_WEIGHT_MIN + ", " + FONT_WEIGHT_MAX + "]");
210         Preconditions.checkArgument(slant == FONT_SLANT_UPRIGHT || slant == FONT_SLANT_ITALIC,
211                 "slant value must be FONT_SLANT_UPRIGHT or FONT_SLANT_UPRIGHT");
212         mWeight = weight;
213         mSlant = slant;
214     }
215 
216 
217      /**
218       * Gets the weight value
219       *
220       * @see #FontStyle(int, int)
221       * @return a weight value
222       */
getWeight()223     public @IntRange(from = 0, to = 1000) int getWeight() {
224         return mWeight;
225     }
226 
227     /**
228      * Gets the slant value
229      *
230      * @return a slant value
231      */
getSlant()232     public @FontSlant int getSlant() {
233         return mSlant;
234     }
235 
236     /**
237      * Compute the matching score for another style.
238      *
239      * The smaller is better.
240      * @hide
241      */
getMatchScore(@onNull FontStyle o)242     public int getMatchScore(@NonNull FontStyle o) {
243         return Math.abs((getWeight() - o.getWeight())) / 100 + (getSlant() == o.getSlant() ? 0 : 2);
244     }
245 
246     @Override
equals(@ullable Object o)247     public boolean equals(@Nullable Object o) {
248         if (o == this) {
249             return true;
250         }
251         if (o == null || !(o instanceof FontStyle)) {
252             return false;
253         }
254         FontStyle fontStyle = (FontStyle) o;
255         return fontStyle.mWeight == mWeight && fontStyle.mSlant == mSlant;
256     }
257 
258     @Override
hashCode()259     public int hashCode() {
260         return Objects.hash(mWeight, mSlant);
261     }
262 
263     @Override
toString()264     public String toString() {
265         return "FontStyle { weight=" + mWeight + ", slant=" + mSlant + "}";
266     }
267 }
268