1 /*
<lambda>null2  * Copyright 2022 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 androidx.compose.ui.text.font
18 
19 import android.content.Context
20 import android.graphics.Typeface
21 import androidx.compose.ui.text.ExperimentalTextApi
22 import androidx.compose.ui.text.font.FontLoadingStrategy.Companion.Async
23 import androidx.compose.ui.text.font.FontLoadingStrategy.Companion.Blocking
24 import androidx.compose.ui.text.font.FontLoadingStrategy.Companion.OptionalLocal
25 import androidx.core.content.res.ResourcesCompat
26 import kotlin.coroutines.resume
27 import kotlin.runCatching
28 import kotlinx.coroutines.suspendCancellableCoroutine
29 
30 /** Android implementation for [Font.ResourceLoader]. It is designed to load only [ResourceFont]. */
31 internal class AndroidFontLoader(context: Context) : PlatformFontLoader {
32     private val context = context.applicationContext
33 
34     @OptIn(ExperimentalTextApi::class)
35     override fun loadBlocking(font: Font): Typeface? {
36         return when (font) {
37             is AndroidFont -> font.typefaceLoader.loadBlocking(context, font)
38             is ResourceFont ->
39                 when (font.loadingStrategy) {
40                     Blocking -> font.load(context)
41                     OptionalLocal -> runCatching { font.load(context) }.getOrNull()
42                     Async -> throw UnsupportedOperationException("Unsupported Async font load path")
43                     else ->
44                         throw IllegalArgumentException(
45                             "Unknown loading type ${font.loadingStrategy}"
46                         )
47                 }.setFontVariationSettings(font.variationSettings, context)
48             else -> null
49         }
50     }
51 
52     @OptIn(ExperimentalTextApi::class)
53     override suspend fun awaitLoad(font: Font): Typeface? {
54         return when (font) {
55             is AndroidFont -> font.typefaceLoader.awaitLoad(context, font)
56             is ResourceFont ->
57                 font.loadAsync(context).setFontVariationSettings(font.variationSettings, context)
58             else -> throw IllegalArgumentException("Unknown font type: $font")
59         }
60     }
61 
62     override val cacheKey: Any? = null
63 }
64 
loadnull65 private fun ResourceFont.load(context: Context): Typeface =
66     ResourcesCompat.getFont(context, resId)!!
67 
68 // TODO(seanmcq): Move to core-ktx to dedup
69 private suspend fun ResourceFont.loadAsync(context: Context): Typeface {
70     return suspendCancellableCoroutine { continuation ->
71         ResourcesCompat.getFont(
72             context,
73             resId,
74             object : ResourcesCompat.FontCallback() {
75                 override fun onFontRetrieved(typeface: Typeface) {
76                     continuation.resume(typeface)
77                 }
78 
79                 override fun onFontRetrievalFailed(reason: Int) {
80                     continuation.cancel(
81                         IllegalStateException(
82                             "Unable to load font ${this@loadAsync} (reason=$reason)"
83                         )
84                     )
85                 }
86             },
87             null
88         )
89     }
90 }
91