up

app/src/main/java/io/legado/app/help/AdapterDataObserverProxy.kt

@@ -0,0 +1,30 @@
+package io.legado.app.help
+
+import androidx.recyclerview.widget.RecyclerView
+
+internal class AdapterDataObserverProxy(var adapterDataObserver: RecyclerView.AdapterDataObserver, var headerCount: Int) : RecyclerView.AdapterDataObserver() {
+    override fun onChanged() {
+        adapterDataObserver.onChanged()
+    }
+
+    override fun onItemRangeChanged(positionStart: Int, itemCount: Int) {
+        adapterDataObserver.onItemRangeChanged(positionStart + headerCount, itemCount)
+    }
+
+    override fun onItemRangeChanged(positionStart: Int, itemCount: Int, payload: Any?) {
+        adapterDataObserver.onItemRangeChanged(positionStart + headerCount, itemCount, payload)
+    }
+
+    // 当第n个数据被获取，更新第n+1个position
+    override fun onItemRangeInserted(positionStart: Int, itemCount: Int) {
+        adapterDataObserver.onItemRangeInserted(positionStart + headerCount, itemCount)
+    }
+
+    override fun onItemRangeRemoved(positionStart: Int, itemCount: Int) {
+        adapterDataObserver.onItemRangeRemoved(positionStart + headerCount, itemCount)
+    }
+
+    override fun onItemRangeMoved(fromPosition: Int, toPosition: Int, itemCount: Int) {
+        super.onItemRangeMoved(fromPosition + headerCount, toPosition + headerCount, itemCount)
+    }
+}

app/src/main/java/io/legado/app/ui/main/bookshelf/BookGroupAdapter.kt

@@ -8,6 +8,7 @@ import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.RecyclerView
 import io.legado.app.R
 import io.legado.app.data.entities.BookGroup
+import io.legado.app.help.AdapterDataObserverProxy
 import kotlinx.android.synthetic.main.item_book_group.view.*
 
 class BookGroupAdapter : PagedListAdapter<BookGroup, BookGroupAdapter.MyViewHolder>(DIFF_CALLBACK) {
@@ -26,12 +27,18 @@ class BookGroupAdapter : PagedListAdapter<BookGroup, BookGroupAdapter.MyViewHold
     }
 
     var callBack: CallBack? = null
-    private val defaultGroups = arrayOf(BookGroup(-5, "全部"),
-            BookGroup(-5, "本地"),
-            BookGroup(-5, "音频"))
+    private val defaultGroups = arrayOf(BookGroup(-1, "全部"),
+            BookGroup(-2, "本地"),
+            BookGroup(-3, "音频"))
+
+    private val addBookGroup = BookGroup(-10, "+")
 
     override fun getItemCount(): Int {
-        return super.getItemCount() + defaultGroups.size
+        return super.getItemCount() + defaultGroups.size + 1
+    }
+
+    override fun registerAdapterDataObserver(observer: RecyclerView.AdapterDataObserver) {
+        super.registerAdapterDataObserver(AdapterDataObserverProxy(observer, defaultGroups.size))
     }
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
@@ -41,6 +48,8 @@ class BookGroupAdapter : PagedListAdapter<BookGroup, BookGroupAdapter.MyViewHold
     override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
         if (position < defaultGroups.size) {
             holder.bind(defaultGroups[position], callBack)
+        } else if (position == itemCount - 1) {
+            holder.bind(addBookGroup, callBack)
         } else {
             currentList?.get(position - defaultGroups.size)?.let {
                 holder.bind(it, callBack)
@@ -52,10 +61,11 @@ class BookGroupAdapter : PagedListAdapter<BookGroup, BookGroupAdapter.MyViewHold
 
         fun bind(bookGroup: BookGroup, callBack: CallBack?) = with(itemView) {
             tv_group.text = bookGroup.groupName
+            tv_group.setOnClickListener { callBack?.open(bookGroup.groupId) }
         }
     }
 
     interface CallBack {
-
+        fun open(groupId: Int)
     }
 }