refactor: transform FlexibleAdapter with BaseDifferAdapter

app/src/main/java/com/osfans/trime/data/db/ClipboardHelper.kt

@@ -90,6 +90,8 @@ object ClipboardHelper :
 
     suspend fun get(id: Int) = clbDao.get(id)
 
+    suspend fun haveUnpinned() = clbDao.haveUnpinned()
+
     suspend fun getAll() = clbDao.getAll()
 
     suspend fun pin(id: Int) = clbDao.updatePinned(id, true)
@@ -107,6 +109,7 @@ object ClipboardHelper :
         } else {
             clbDao.deleteAll()
         }
+        updateItemCount()
     }
 
     /**

app/src/main/java/com/osfans/trime/data/db/CollectionHelper.kt

@@ -25,6 +25,8 @@ object CollectionHelper : CoroutineScope by CoroutineScope(SupervisorJob() + Dis
 
     suspend fun insert(bean: DatabaseBean) = cltDao.insert(bean)
 
+    suspend fun haveUnpinned() = cltDao.haveUnpinned()
+
     suspend fun getAll() = cltDao.getAll()
 
     suspend fun pin(id: Int) = cltDao.updatePinned(id, true)

app/src/main/java/com/osfans/trime/data/db/DatabaseDao.kt

@@ -48,7 +48,7 @@ interface DatabaseDao {
     @Query("DELETE FROM ${DatabaseBean.TABLE_NAME} WHERE NOT pinned")
     suspend fun deleteAllUnpinned()
 
-    @Query("SELECT * FROM ${DatabaseBean.TABLE_NAME}")
+    @Query("SELECT * FROM ${DatabaseBean.TABLE_NAME} ORDER BY pinned DESC, time DESC")
     suspend fun getAll(): List<DatabaseBean>
 
     @Query("SELECT * FROM ${DatabaseBean.TABLE_NAME} WHERE id=:id LIMIT 1")
@@ -57,6 +57,9 @@ interface DatabaseDao {
     @Query("SELECT * FROM ${DatabaseBean.TABLE_NAME} WHERE rowId=:rowId LIMIT 1")
     suspend fun get(rowId: Long): DatabaseBean?
 
+    @Query("SELECT EXISTS(SELECT 1 FROM ${DatabaseBean.TABLE_NAME} WHERE pinned=0)")
+    suspend fun haveUnpinned(): Boolean
+
     @Query("SELECT COUNT(*) FROM ${DatabaseBean.TABLE_NAME}")
     suspend fun itemCount(): Int
 }

app/src/main/java/com/osfans/trime/data/db/DraftHelper.kt

@@ -53,6 +53,8 @@ object DraftHelper : CoroutineScope by CoroutineScope(SupervisorJob() + Dispatch
 
     suspend fun get(id: Int) = dftDao.get(id)
 
+    suspend fun haveUnpinned() = dftDao.haveUnpinned()
+
     suspend fun getAll() = dftDao.getAll()
 
     suspend fun pin(id: Int) = dftDao.updatePinned(id, true)
@@ -75,6 +77,7 @@ object DraftHelper : CoroutineScope by CoroutineScope(SupervisorJob() + Dispatch
         } else {
             dftDao.deleteAll()
         }
+        updateItemCount()
     }
 
     fun onInputEventChanged() {

app/src/main/java/com/osfans/trime/ime/symbol/DbAdapter.kt

@@ -18,7 +18,7 @@ import com.osfans.trime.util.ShortcutUtils
 import kotlinx.coroutines.launch
 
 class DbAdapter(
-    private val context: Context,
+    private val ctx: Context,
     private val service: TrimeInputMethodService,
     theme: Theme,
 ) : FlexibleAdapter(theme) {
@@ -34,8 +34,9 @@ class DbAdapter(
                 SymbolBoardType.CLIPBOARD -> ClipboardHelper.pin(bean.id)
                 SymbolBoardType.COLLECTION -> CollectionHelper.pin(bean.id)
                 SymbolBoardType.DRAFT -> DraftHelper.pin(bean.id)
-                else -> return@launch
+                else -> {}
             }
+            refresh()
         }
     }
 
@@ -45,8 +46,9 @@ class DbAdapter(
                 SymbolBoardType.CLIPBOARD -> ClipboardHelper.unpin(bean.id)
                 SymbolBoardType.COLLECTION -> CollectionHelper.unpin(bean.id)
                 SymbolBoardType.DRAFT -> DraftHelper.unpin(bean.id)
-                else -> return@launch
+                else -> {}
             }
+            refresh()
         }
     }
 
@@ -56,13 +58,14 @@ class DbAdapter(
                 SymbolBoardType.CLIPBOARD -> ClipboardHelper.delete(bean.id)
                 SymbolBoardType.COLLECTION -> CollectionHelper.delete(bean.id)
                 SymbolBoardType.DRAFT -> DraftHelper.delete(bean.id)
-                else -> return@launch
+                else -> {}
             }
+            refresh()
         }
     }
 
     override fun onEdit(bean: DatabaseBean) {
-        bean.text?.let { ShortcutUtils.launchLiquidKeyboardEdit(context, type, bean.id, it) }
+        bean.text?.let { ShortcutUtils.launchLiquidKeyboardEdit(ctx, type, bean.id, it) }
     }
 
     override fun onCollect(bean: DatabaseBean) {
@@ -71,54 +74,34 @@ class DbAdapter(
 
     // FIXME: 这个方法可能实现得比较粗糙，需要日后改进
     override fun onDeleteAll() {
-        fun deleteAll() {
-            if (beans.all { it.pinned }) {
-                // 如果没有未置顶的条目，则删除所有已置顶的条目
-                service.lifecycleScope.launch {
-                    when (type) {
-                        SymbolBoardType.CLIPBOARD -> ClipboardHelper.deleteAll(false)
-                        SymbolBoardType.COLLECTION -> CollectionHelper.deleteAll(false)
-                        SymbolBoardType.DRAFT -> DraftHelper.deleteAll(false)
-                        else -> return@launch
-                    }
-                }
-                updateBeans(emptyList())
-            } else {
-                // 如果有已置顶的条目，则删除所有未置顶的条目
-                service.lifecycleScope.launch {
-                    when (type) {
-                        SymbolBoardType.CLIPBOARD -> {
-                            ClipboardHelper.deleteAll()
-                            updateBeans(ClipboardHelper.getAll())
-                        }
-
-                        SymbolBoardType.COLLECTION -> {
-                            CollectionHelper.deleteAll()
-                            updateBeans(CollectionHelper.getAll())
-                        }
-
-                        SymbolBoardType.DRAFT -> {
-                            DraftHelper.deleteAll()
-                            updateBeans(DraftHelper.getAll())
-                        }
-
-                        else -> return@launch
-                    }
-                }
-            }
-        }
-
         val confirm =
             AlertDialog
                 .Builder(context)
                 .setTitle(R.string.delete_all)
                 .setMessage(R.string.liquid_keyboard_ask_to_delete_all)
                 .setPositiveButton(R.string.ok) { _, _ ->
-                    deleteAll()
+                    service.lifecycleScope.launch {
+                        when (type) {
+                            SymbolBoardType.CLIPBOARD -> ClipboardHelper.deleteAll(ClipboardHelper.haveUnpinned())
+                            SymbolBoardType.COLLECTION -> CollectionHelper.deleteAll(CollectionHelper.haveUnpinned())
+                            SymbolBoardType.DRAFT -> DraftHelper.deleteAll(DraftHelper.haveUnpinned())
+                            else -> {}
+                        }
+                        refresh()
+                    }
                 }.setNegativeButton(R.string.cancel, null)
                 .create()
         service.inputView?.showDialog(confirm)
     }
 
     override val showCollectButton: Boolean = type != SymbolBoardType.COLLECTION
+
+    private suspend fun refresh() {
+        when (type) {
+            SymbolBoardType.CLIPBOARD -> submitList(ClipboardHelper.getAll())
+            SymbolBoardType.COLLECTION -> submitList(CollectionHelper.getAll())
+            SymbolBoardType.DRAFT -> submitList(DraftHelper.getAll())
+            else -> {}
+        }
+    }
 }

app/src/main/java/com/osfans/trime/ime/symbol/FlexibleAdapter.kt

@@ -4,12 +4,15 @@
 
 package com.osfans.trime.ime.symbol
 
+import android.content.Context
 import android.os.Build
 import android.view.ViewGroup
 import android.widget.PopupMenu
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
+import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.RecyclerView
+import com.chad.library.adapter4.BaseDifferAdapter
 import com.osfans.trime.R
 import com.osfans.trime.data.db.DatabaseBean
 import com.osfans.trime.data.theme.Theme
@@ -19,79 +22,63 @@ import kotlin.math.min
 
 abstract class FlexibleAdapter(
     private val theme: Theme,
-) : RecyclerView.Adapter<FlexibleAdapter.ViewHolder>() {
-    private val mBeans = mutableListOf<DatabaseBean>()
-
-    // 映射条目的 id 和其在视图中位置的关系
-    // 以应对增删条目时 id 和其位置的相对变化
-    // [<id, position>, ...]
-    private val mBeansId = mutableMapOf<Int, Int>()
-    val beans get() = mBeans
-
-    fun updateBeans(beans: List<DatabaseBean>) {
-        val sorted =
-            beans.sortedWith { b1, b2 ->
-                when {
-                    // 如果 b1 置顶而 b2 没置顶，则 b1 比 b2 小，排前面
-                    b1.pinned && !b2.pinned -> -1
-                    // 如果 b1 没置顶而 b2 置顶，则 b1 比 b2 大，排后面
-                    !b1.pinned && b2.pinned -> 1
-                    // 如果都置顶了或都没置顶，则比较 id，id 大的排前面
-                    else -> b2.id.compareTo(b1.id)
-                }
+) : BaseDifferAdapter<DatabaseBean, FlexibleAdapter.ViewHolder>(diffCallback) {
+    companion object {
+        private val diffCallback =
+            object : DiffUtil.ItemCallback<DatabaseBean>() {
+                override fun areItemsTheSame(
+                    oldItem: DatabaseBean,
+                    newItem: DatabaseBean,
+                ): Boolean = oldItem.id == newItem.id
+
+                override fun areContentsTheSame(
+                    oldItem: DatabaseBean,
+                    newItem: DatabaseBean,
+                ): Boolean = oldItem == newItem
             }
-        val prevSize = mBeans.size
-        mBeans.clear()
-        notifyItemRangeRemoved(0, prevSize)
-        mBeans.addAll(sorted)
-        notifyItemRangeChanged(0, sorted.size)
-        mBeansId.clear()
-        mBeans.forEachIndexed { index: Int, (id): DatabaseBean ->
-            mBeansId[id] = index
-        }
-    }
 
-    private fun excerptText(
-        str: String,
-        lines: Int = 4,
-        chars: Int = 128,
-    ): String =
-        buildString {
-            val length = str.length
-            var lineBreak = -1
-            for (i in 1..lines) {
-                val start = lineBreak + 1 // skip previous '\n'
-                val excerptEnd = min(start + chars, length)
-                lineBreak = str.indexOf('\n', start)
-                if (lineBreak < 0) {
-                    // no line breaks remaining, substring to end of text
-                    append(str.substring(start, excerptEnd))
-                    break
-                } else {
-                    val end = min(excerptEnd, lineBreak)
-                    // append one line exactly
-                    appendLine(str.substring(start, end))
+        private fun excerptText(
+            str: String,
+            lines: Int = 4,
+            chars: Int = 128,
+        ): String =
+            buildString {
+                val length = str.length
+                var lineBreak = -1
+                for (i in 1..lines) {
+                    val start = lineBreak + 1 // skip previous '\n'
+                    val excerptEnd = min(start + chars, length)
+                    lineBreak = str.indexOf('\n', start)
+                    if (lineBreak < 0) {
+                        // no line breaks remaining, substring to end of text
+                        append(str.substring(start, excerptEnd))
+                        break
+                    } else {
+                        val end = min(excerptEnd, lineBreak)
+                        // append one line exactly
+                        appendLine(str.substring(start, end))
+                    }
                 }
             }
-        }
-
-    override fun getItemCount(): Int = mBeans.size
+    }
 
     override fun onCreateViewHolder(
+        context: Context,
         parent: ViewGroup,
         viewType: Int,
-    ): ViewHolder = ViewHolder(SimpleItemUi(parent.context, theme))
+    ): ViewHolder = ViewHolder(SimpleItemUi(context, theme))
 
     class ViewHolder(
         val ui: SimpleItemUi,
     ) : RecyclerView.ViewHolder(ui.root)
 
     override fun onBindViewHolder(
-        viewHolder: ViewHolder,
+        holder: ViewHolder,
         position: Int,
+        item: DatabaseBean?,
     ) {
-        with(viewHolder.ui) {
-            val bean = mBeans[position]
+        with(holder.ui) {
+            val bean = item ?: return
             setItem(excerptText(bean.text ?: ""), bean.pinned)
             root.setOnClickListener {
                 onPaste(bean)
@@ -119,12 +106,10 @@ abstract class FlexibleAdapter(
                 if (bean.pinned) {
                     menuItem(R.string.simple_key_unpin, R.drawable.ic_outline_push_pin_24) {
                         onUnpin(bean)
-                        setPinStatus(bean.id, false)
                     }
                 } else {
                     menuItem(R.string.simple_key_pin, R.drawable.ic_baseline_push_pin_24) {
                         onPin(bean)
-                        setPinStatus(bean.id, true)
                     }
                 }
                 if (showCollectButton) {
@@ -134,12 +119,9 @@ abstract class FlexibleAdapter(
                 }
                 menuItem(R.string.delete, R.drawable.ic_baseline_delete_24) {
                     onDelete(bean)
-                    delete(bean.id)
                 }
-                if (beans.isNotEmpty()) {
-                    menuItem(R.string.delete_all, R.drawable.ic_baseline_delete_sweep_24) {
-                        onDeleteAll()
-                    }
+                menuItem(R.string.delete_all, R.drawable.ic_baseline_delete_sweep_24) {
+                    onDeleteAll()
                 }
                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
                     menu.setForceShowIcon(true)
@@ -150,26 +132,6 @@ abstract class FlexibleAdapter(
         }
     }
 
-    private fun delete(id: Int) {
-        val position = mBeansId.getValue(id)
-        mBeans.removeAt(position)
-        mBeansId.remove(id)
-        for (i in position until mBeans.size) {
-            mBeansId[mBeans[i].id] = i
-        }
-        notifyItemRemoved(position)
-    }
-
-    private fun setPinStatus(
-        id: Int,
-        pinned: Boolean,
-    ) {
-        val position = mBeansId.getValue(id)
-        mBeans[position] = mBeans[position].copy(pinned = pinned)
-        // 置顶会改变条目的排列顺序
-        updateBeans(mBeans)
-    }
-
     abstract fun onPaste(bean: DatabaseBean)
 
     abstract fun onPin(bean: DatabaseBean)

app/src/main/java/com/osfans/trime/ime/symbol/LiquidKeyboard.kt

@@ -207,7 +207,7 @@ class LiquidKeyboard(
         }
 
         service.lifecycleScope.launch {
-            dbAdapter.updateBeans(data())
+            dbAdapter.submitList(data())
         }
     }
 
@@ -246,7 +246,7 @@ class LiquidKeyboard(
         if (currentBoardType == SymbolBoardType.CLIPBOARD) {
             Timber.v("OnClipboardUpdateListener onUpdate: update clipboard view")
             service.lifecycleScope.launch {
-                dbAdapter.updateBeans(ClipboardHelper.getAll())
+                dbAdapter.submitList(ClipboardHelper.getAll())
             }
         }
     }