添加 ItemTouchHelperCallback 支持拖拽和删除

Author: Goooler

adapter/src/main/kotlin/io/goooler/demoapp/adapter/rv/core/ItemTouchHelperCallback.kt

@@ -0,0 +1,45 @@
+package io.goooler.demoapp.adapter.rv.core
+
+import androidx.recyclerview.widget.ItemTouchHelper
+import androidx.recyclerview.widget.RecyclerView
+
+class ItemTouchHelperCallback(
+  private val listener: ItemChangeListener,
+  private val longPressDragEnabled: Boolean = true,
+  private val itemViewSwipeEnabled: Boolean = false
+) : ItemTouchHelper.Callback() {
+
+  override fun isLongPressDragEnabled(): Boolean = longPressDragEnabled
+
+  override fun isItemViewSwipeEnabled(): Boolean = itemViewSwipeEnabled
+
+  override fun getMovementFlags(
+    recyclerView: RecyclerView,
+    viewHolder: RecyclerView.ViewHolder
+  ): Int {
+    val dragFlags = ItemTouchHelper.UP or ItemTouchHelper.DOWN or
+      ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
+    val swipeFlags = ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
+    return makeMovementFlags(dragFlags, swipeFlags)
+  }
+
+  override fun onMove(
+    recyclerView: RecyclerView,
+    from: RecyclerView.ViewHolder,
+    to: RecyclerView.ViewHolder
+  ): Boolean {
+    listener.onItemMove(from.bindingAdapterPosition, to.bindingAdapterPosition)
+    return true
+  }
+
+  override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
+    listener.onItemDismiss(viewHolder.bindingAdapterPosition)
+  }
+
+  interface ItemChangeListener {
+
+    fun onItemMove(fromPosition: Int, toPosition: Int)
+
+    fun onItemDismiss(position: Int)
+  }
+}

main/src/main/kotlin/io/goooler/demoapp/main/ui/fragment/MainSrlFragment.kt

@@ -1,9 +1,11 @@
 package io.goooler.demoapp.main.ui.fragment
 
 import android.view.View
+import androidx.recyclerview.widget.ItemTouchHelper
 import com.scwang.smart.refresh.layout.api.RefreshLayout
 import com.scwang.smart.refresh.layout.listener.OnRefreshLoadMoreListener
 import dagger.hilt.android.AndroidEntryPoint
+import io.goooler.demoapp.adapter.rv.core.ItemTouchHelperCallback
 import io.goooler.demoapp.base.util.unsafeLazy
 import io.goooler.demoapp.common.base.BaseThemeLazyFragment
 import io.goooler.demoapp.common.util.enableRefreshAndLoadMore
@@ -37,11 +39,14 @@ class MainSrlFragment : BaseThemeLazyFragment<MainSrlFragmentBinding>() {
       it.refreshLayout.setOnRefreshLoadMoreListener(listener)
       it.rvList.adapter = rvAdapter
     }
+    ItemTouchHelper(ItemTouchHelperCallback(listener, itemViewSwipeEnabled = true))
+      .attachToRecyclerView(binding.rvList)
   }
 
   private val listener = object :
     MainSrlRvAdapter.OnEventListener,
     OnRefreshLoadMoreListener,
+    ItemTouchHelperCallback.ItemChangeListener,
     View.OnClickListener {
     override fun onContentClick(content: String) {
       content.showToast()
@@ -55,6 +60,14 @@ class MainSrlFragment : BaseThemeLazyFragment<MainSrlFragmentBinding>() {
       vm.loadMore()
     }
 
+    override fun onItemMove(fromPosition: Int, toPosition: Int) {
+      vm.swapItems(fromPosition, toPosition)
+    }
+
+    override fun onItemDismiss(position: Int) {
+      vm.deleteItem(position)
+    }
+
     override fun onClick(v: View) {
       when (v.id) {
         R.id.iv_error, R.id.tv_tip -> {

main/src/main/kotlin/io/goooler/demoapp/main/vm/MainSrlViewModel.kt

@@ -7,6 +7,7 @@ import io.goooler.demoapp.common.base.BaseRxViewModel
 import io.goooler.demoapp.common.type.CommonConstants
 import io.goooler.demoapp.main.model.MainCommonVhModel
 import io.goooler.demoapp.main.repository.MainCommonRepository
+import java.util.Collections
 import javax.inject.Inject
 
 @HiltViewModel
@@ -38,6 +39,16 @@ class MainSrlViewModel @Inject constructor(private val repository: MainCommonRep
     fetchListData(page)
   }
 
+  fun swapItems(fromPosition: Int, toPosition: Int) {
+    Collections.swap(_listData, fromPosition, toPosition)
+    listData.value = _listData
+  }
+
+  fun deleteItem(position: Int) {
+    _listData.removeAt(position)
+    listData.value = _listData
+  }
+
   private fun fetchListData(page: Int) {
     repository.getRepoListWithRx("goooler", page)
       .doFinally(::finishRefreshAndLoadMore)