feat: 优化代码

app/src/main/java/io/legado/app/ui/download/DownloadActivity.kt

@@ -11,12 +11,15 @@ import io.legado.app.R
 import io.legado.app.base.BaseActivity
 import io.legado.app.constant.EventBus
 import io.legado.app.data.entities.Book
+import io.legado.app.help.BookHelp
 import io.legado.app.service.help.Download
 import io.legado.app.utils.applyTint
 import io.legado.app.utils.observeEvent
 import kotlinx.android.synthetic.main.activity_download.*
+import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Dispatchers.IO
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 
 
 class DownloadActivity : BaseActivity(R.layout.activity_download) {
@@ -63,9 +66,28 @@ class DownloadActivity : BaseActivity(R.layout.activity_download) {
         bookshelfLiveData = App.db.bookDao().observeDownload()
         bookshelfLiveData?.observe(this, Observer {
             adapter.setItems(it)
+            initCacheSize(it)
         })
     }
 
+    private fun initCacheSize(books: List<Book>) {
+        launch(IO) {
+            books.forEach { book ->
+                val chapterCaches = hashSetOf<String>()
+                val cacheNames = BookHelp.getChapterFiles(book)
+                App.db.bookChapterDao().getChapterList(book.bookUrl).forEach { chapter ->
+                    if (cacheNames.contains(BookHelp.formatChapterName(chapter))) {
+                        chapterCaches.add(chapter.url)
+                    }
+                }
+                adapter.cacheChapters[book.bookUrl] = chapterCaches
+                withContext(Dispatchers.Main) {
+                    adapter.notifyItemRangeChanged(0, adapter.getActualItemCount(), true)
+                }
+            }
+        }
+    }
+
     override fun observeLiveBus() {
         observeEvent<Boolean>(EventBus.UP_DOWNLOAD) {
             if (it) {

app/src/main/java/io/legado/app/ui/download/DownloadAdapter.kt

@@ -11,6 +11,8 @@ import kotlinx.android.synthetic.main.item_download.view.*
 class DownloadAdapter(context: Context) :
     SimpleRecyclerAdapter<Book>(context, R.layout.item_download) {
 
+    val cacheChapters = hashMapOf<String, HashSet<String>>()
+
     override fun convert(holder: ItemViewHolder, item: Book, payloads: MutableList<Any>) {
         with(holder.itemView) {
             if (payloads.isEmpty()) {
@@ -18,9 +20,9 @@ class DownloadAdapter(context: Context) :
                 tv_author.text = context.getString(R.string.author_show, item.getRealAuthor())
                 tv_download.setText(R.string.loading)
             } else {
-                val count = payloads[0] as Int
+                val cacheSize = cacheChapters[item.bookUrl]?.size ?: 0
                 tv_download.text =
-                    context.getString(R.string.download_count, count, item.totalChapterNum)
+                    context.getString(R.string.download_count, cacheSize, item.totalChapterNum)
             }
         }
     }