feat: 优化代码

app/src/main/java/io/legado/app/App.kt

@@ -48,12 +48,8 @@ class App : Application() {
             versionCode = it.versionCode
             versionName = it.versionName
         }
-
-        if (!ThemeStore.isConfigured(this, versionCode)) applyTheme()
-        initNightMode()
-
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) createChannelId()
-
+        applyDayNight()
         LiveEventBus.get()
             .config()
             .supportBroadcast(this)

app/src/main/java/io/legado/app/ui/book/read/page/ChapterProvider.kt

@@ -231,7 +231,7 @@ object ChapterProvider {
         textLine.text = "$words\n"
         var x = startX
         for (i in words.indices) {
-            val char = words[i].toString()
+            val char = words.substring(i, i + 1)
             val cw = StaticLayout.getDesiredWidth(char, textPaint)
             val x1 = x + cw
             textLine.addTextChar(