优化

app/src/main/java/io/legado/app/data/dao/BookSourceDao.kt

@@ -7,12 +7,15 @@ import io.legado.app.data.entities.BookSource
 @Dao
 interface BookSourceDao {
 
-    @Query("select * from book_sources")
+    @Query("select * from book_sources order by customOrder asc")
     fun observeAll(): DataSource.Factory<Int, BookSource>
 
     @Query("select * from book_sources where origin = :key")
     fun findByKey(key:String): BookSource?
 
+    @Query("select count(*) from book_sources")
+    fun allCount(): Int
+
     @Insert(onConflict = OnConflictStrategy.REPLACE)
     fun insert(bookSource: BookSource): Long
 

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

@@ -0,0 +1,127 @@
+package io.legado.app.help
+
+
+import androidx.recyclerview.widget.GridLayoutManager
+import androidx.recyclerview.widget.ItemTouchHelper
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
+import androidx.swiperefreshlayout.widget.SwipeRefreshLayout
+import androidx.viewpager.widget.ViewPager
+
+/**
+ * Created by GKF on 2018/3/16.
+ */
+
+class ItemTouchCallback : ItemTouchHelper.Callback() {
+
+    private var swipeRefreshLayout: SwipeRefreshLayout? = null
+    private var viewPager: ViewPager? = null
+
+    /**
+     * Item操作的回调
+     */
+    var onItemTouchCallbackListener: OnItemTouchCallbackListener? = null
+
+    /**
+     * 是否可以拖拽
+     */
+    var isCanDrag = false
+    /**
+     * 是否可以被滑动
+     */
+    var isCanSwipe = false
+
+    /**
+     * 当Item被长按的时候是否可以被拖拽
+     */
+    override fun isLongPressDragEnabled(): Boolean {
+        return isCanDrag
+    }
+
+    /**
+     * Item是否可以被滑动(H：左右滑动，V：上下滑动)
+     */
+    override fun isItemViewSwipeEnabled(): Boolean {
+        return isCanSwipe
+    }
+
+    /**
+     * 当用户拖拽或者滑动Item的时候需要我们告诉系统滑动或者拖拽的方向
+     */
+    override fun getMovementFlags(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder): Int {
+        val layoutManager = recyclerView.layoutManager
+        if (layoutManager is GridLayoutManager) {// GridLayoutManager
+            // flag如果值是0，相当于这个功能被关闭
+            val dragFlag = ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT or ItemTouchHelper.UP or ItemTouchHelper.DOWN
+            val swipeFlag = 0
+            // create make
+            return makeMovementFlags(dragFlag, swipeFlag)
+        } else if (layoutManager is LinearLayoutManager) {// linearLayoutManager
+            val linearLayoutManager = layoutManager as LinearLayoutManager?
+            val orientation = linearLayoutManager!!.orientation
+
+            var dragFlag = 0
+            var swipeFlag = 0
+
+            // 为了方便理解，相当于分为横着的ListView和竖着的ListView
+            if (orientation == LinearLayoutManager.HORIZONTAL) {// 如果是横向的布局
+                swipeFlag = ItemTouchHelper.UP or ItemTouchHelper.DOWN
+                dragFlag = ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
+            } else if (orientation == LinearLayoutManager.VERTICAL) {// 如果是竖向的布局，相当于ListView
+                dragFlag = ItemTouchHelper.UP or ItemTouchHelper.DOWN
+                swipeFlag = ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
+            }
+            return makeMovementFlags(dragFlag, swipeFlag)
+        }
+        return 0
+    }
+
+    /**
+     * 当Item被拖拽的时候被回调
+     *
+     * @param recyclerView     recyclerView
+     * @param srcViewHolder    拖拽的ViewHolder
+     * @param targetViewHolder 目的地的viewHolder
+     */
+    override fun onMove(
+        recyclerView: RecyclerView,
+        srcViewHolder: RecyclerView.ViewHolder,
+        targetViewHolder: RecyclerView.ViewHolder
+    ): Boolean {
+        onItemTouchCallbackListener?.let {
+            return it.onMove(srcViewHolder.adapterPosition, targetViewHolder.adapterPosition)
+        }
+        return false
+    }
+
+    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
+        onItemTouchCallbackListener?.let {
+            return it.onSwiped(viewHolder.adapterPosition)
+        }
+    }
+
+    override fun onSelectedChanged(viewHolder: RecyclerView.ViewHolder?, actionState: Int) {
+        super.onSelectedChanged(viewHolder, actionState)
+        val swiping = actionState == ItemTouchHelper.ACTION_STATE_DRAG
+        swipeRefreshLayout?.isEnabled = !swiping
+        viewPager?.requestDisallowInterceptTouchEvent(swiping)
+    }
+
+    interface OnItemTouchCallbackListener {
+        /**
+         * 当某个Item被滑动删除的时候
+         *
+         * @param adapterPosition item的position
+         */
+        fun onSwiped(adapterPosition: Int)
+
+        /**
+         * 当两个Item位置互换的时候被回调
+         *
+         * @param srcPosition    拖拽的item的position
+         * @param targetPosition 目的地的Item的position
+         * @return 开发者处理了操作应该返回true，开发者没有处理就返回false
+         */
+        fun onMove(srcPosition: Int, targetPosition: Int): Boolean
+    }
+}

app/src/main/java/io/legado/app/ui/main/booksource/BookSourceAdapter.kt

@@ -11,8 +11,12 @@ import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.RecyclerView
 import io.legado.app.R
 import io.legado.app.data.entities.BookSource
+import io.legado.app.help.ItemTouchCallback
+import io.legado.app.help.ItemTouchCallback.OnItemTouchCallbackListener
 import kotlinx.android.synthetic.main.item_book_source.view.*
 import org.jetbrains.anko.sdk27.listeners.onClick
+import java.util.*
+import kotlin.collections.HashSet
 
 class BookSourceAdapter : PagedListAdapter<BookSource, BookSourceAdapter.MyViewHolder>(DIFF_CALLBACK) {
 
@@ -34,6 +38,27 @@ class BookSourceAdapter : PagedListAdapter<BookSource, BookSourceAdapter.MyViewH
     var callBack: CallBack? = null
     val checkedList = HashSet<String>()
 
+    val itemTouchCallbackListener = object : OnItemTouchCallbackListener {
+        override fun onSwiped(adapterPosition: Int) {
+
+        }
+
+        override fun onMove(srcPosition: Int, targetPosition: Int): Boolean {
+            currentList?.let {
+                val srcSource = it[srcPosition]
+                val targetSource = it[targetPosition]
+                srcSource?.let { a->
+                    targetSource?.let { b->
+                        a.customOrder = targetPosition
+                        b.customOrder = srcPosition
+                        callBack?.update(a, b)
+                    }
+                }
+            }
+            return true
+        }
+    }
+
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
         return MyViewHolder(LayoutInflater.from(parent.context).inflate(R.layout.item_book_source, parent, false))
     }
@@ -86,5 +111,6 @@ class BookSourceAdapter : PagedListAdapter<BookSource, BookSourceAdapter.MyViewH
         fun del(bookSource: BookSource)
         fun edit(bookSource: BookSource)
         fun update(bookSource: BookSource)
+        fun update(vararg bookSource: BookSource)
     }
 }

app/src/main/java/io/legado/app/ui/main/booksource/BookSourceFragment.kt

@@ -9,12 +9,14 @@ import androidx.lifecycle.Observer
 import androidx.paging.LivePagedListBuilder
 import androidx.paging.PagedList
 import androidx.recyclerview.widget.DividerItemDecoration
+import androidx.recyclerview.widget.ItemTouchHelper
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import io.legado.app.App
 import io.legado.app.R
 import io.legado.app.base.BaseFragment
 import io.legado.app.data.entities.BookSource
+import io.legado.app.help.ItemTouchCallback
 import io.legado.app.ui.sourceedit.SourceEditActivity
 import kotlinx.android.synthetic.main.fragment_book_source.*
 import kotlinx.android.synthetic.main.view_titlebar.*
@@ -51,6 +53,10 @@ class BookSourceFragment : BaseFragment(R.layout.fragment_book_source), BookSour
         adapter = BookSourceAdapter()
         adapter.callBack = this
         recycler_view.adapter = adapter
+        val itemTouchCallback = ItemTouchCallback()
+        itemTouchCallback.onItemTouchCallbackListener = adapter.itemTouchCallbackListener
+        itemTouchCallback.isCanDrag = true
+        ItemTouchHelper(itemTouchCallback).attachToRecyclerView(recycler_view)
     }
 
     private fun initDataObservers() {
@@ -67,6 +73,10 @@ class BookSourceFragment : BaseFragment(R.layout.fragment_book_source), BookSour
         GlobalScope.launch { App.db.bookSourceDao().update(bookSource) }
     }
 
+    override fun update(vararg bookSource: BookSource) {
+        GlobalScope.launch { App.db.bookSourceDao().update(*bookSource) }
+    }
+
     override fun edit(bookSource: BookSource) {
         context?.let { it.startActivity<SourceEditActivity>(Pair("data", bookSource.origin)) }
     }

app/src/main/java/io/legado/app/ui/sourceedit/SourceEditActivity.kt

@@ -54,7 +54,7 @@ class SourceEditActivity : BaseActivity<SourceEditViewModel>() {
                     toast("书源名称和URL不能为空")
                 } else {
                     GlobalScope.launch {
-                        App.db.bookSourceDao().insert(bookSource)
+                        viewModel.save(bookSource)
                         GlobalScope.launch(Dispatchers.Main) { finish() }
                     }
                 }

app/src/main/java/io/legado/app/ui/sourceedit/SourceEditViewModel.kt

@@ -20,6 +20,13 @@ class SourceEditViewModel(application: Application) : AndroidViewModel(applicati
         }
     }
 
+    fun save(bookSource: BookSource) {
+        val source = App.db.bookSourceDao().findByKey(bookSource.origin)
+        if (source == null) {
+            bookSource.customOrder = App.db.bookSourceDao().allCount()
+        }
+        App.db.bookSourceDao().insert(bookSource)
+    }
 
 
 }

app/src/main/res/layout/item_book_source.xml

@@ -2,6 +2,7 @@
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
               android:layout_width="match_parent"
               android:layout_height="wrap_content" xmlns:app="http://schemas.android.com/apk/res-auto"
+              android:background="@color/background"
               android:padding="16dp"
               android:orientation="horizontal"
               android:gravity="center_vertical">