Feature: Reordring (#23)

* Reordering of Servers

* Fix drag handle being drawn outside of the screen

---------

Co-authored-by: Maksim Karasev <karasevm98@gmail.com>

app/src/main/java/ru/karasevm/privatednstoggle/DNSServerDialogFragment.kt

@@ -44,7 +44,7 @@ class DNSServerDialogFragment : DialogFragment() {
             items.add(0, resources.getString(R.string.dns_auto))
             items.add(0, resources.getString(R.string.dns_off))
 
-            adapter = RecyclerAdapter(items)
+            adapter = RecyclerAdapter(items, false)
             binding.recyclerView.adapter = adapter
 
 

app/src/main/java/ru/karasevm/privatednstoggle/MainActivity.kt

@@ -6,15 +6,26 @@ import android.content.Intent
 import android.content.SharedPreferences
 import android.content.pm.IPackageManager
 import android.content.pm.PackageManager
+import android.content.res.Resources
+import android.graphics.Color
+import android.graphics.drawable.Drawable
 import android.net.Uri
 import android.os.Build
 import android.os.Bundle
 import android.permission.IPermissionManager
 import android.util.Log
+import android.util.TypedValue
 import android.view.Menu
 import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
+import androidx.core.content.ContextCompat
+import androidx.recyclerview.widget.ItemTouchHelper
+import androidx.recyclerview.widget.ItemTouchHelper.DOWN
+import androidx.recyclerview.widget.ItemTouchHelper.END
+import androidx.recyclerview.widget.ItemTouchHelper.START
+import androidx.recyclerview.widget.ItemTouchHelper.UP
 import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
 import org.lsposed.hiddenapibypass.HiddenApiBypass
 import rikka.shizuku.Shizuku
 import rikka.shizuku.ShizukuBinderWrapper
@@ -34,6 +45,47 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
     private lateinit var sharedPrefs: SharedPreferences
     private lateinit var adapter: RecyclerAdapter
 
+    private val itemTouchHelper by lazy {
+        val simpleItemTouchCallback =
+            object : ItemTouchHelper.SimpleCallback(UP or
+                    DOWN, 0) {
+
+                override fun onMove(
+                    recyclerView: RecyclerView,
+                    viewHolder: RecyclerView.ViewHolder,
+                    target: RecyclerView.ViewHolder
+                ): Boolean {
+                    adapter.onItemMove(viewHolder.adapterPosition, target.adapterPosition)
+                    return true
+                }
+
+                override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {}
+
+                override fun onSelectedChanged(viewHolder: RecyclerView.ViewHolder?, actionState: Int) {
+                    super.onSelectedChanged(viewHolder, actionState)
+                    if (actionState == ItemTouchHelper.ACTION_STATE_DRAG) {
+                        viewHolder?.itemView?.apply {
+                            // Example: Elevate the view
+                            elevation = 8f
+                            alpha = 0.5f
+                            setBackgroundColor(Color.GRAY)
+                        }
+                    }
+                }
+
+                override fun clearView(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder) {
+                    super.clearView(recyclerView, viewHolder)
+                    viewHolder.itemView.apply {
+                        // Reset the appearance
+                        elevation = 0f
+                        alpha = 1.0f
+                        setBackgroundColor(Color.TRANSPARENT)
+                    }
+                }
+            }
+        ItemTouchHelper(simpleItemTouchCallback)
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
@@ -52,16 +104,24 @@ class MainActivity : AppCompatActivity(), AddServerDialogFragment.NoticeDialogLi
         if (items[0] == "") {
             items.removeAt(0)
         }
-        adapter = RecyclerAdapter(items)
+        adapter = RecyclerAdapter(items, true)
         adapter.onItemClick = { position ->
             val newFragment = DeleteServerDialogFragment(position)
             newFragment.show(supportFragmentManager, "delete_server")
         }
+        adapter.onItemsChanged = { swapedItems ->
+            items = swapedItems
+            sharedPrefs.dns_servers = swapedItems
+        }
+        adapter.onDragStart = { viewHolder ->
+            itemTouchHelper.startDrag(viewHolder);
+        }
         binding.floatingActionButton.setOnClickListener {
             val newFragment = AddServerDialogFragment()
             newFragment.show(supportFragmentManager, "add_server")
         }
         binding.recyclerView.adapter = adapter
+        itemTouchHelper.attachToRecyclerView(binding.recyclerView);
 
         binding.topAppBar.setOnMenuItemClickListener { item ->
             when (item.itemId) {

app/src/main/java/ru/karasevm/privatednstoggle/RecyclerAdapter.kt

@@ -1,15 +1,21 @@
 package ru.karasevm.privatednstoggle
 
+import android.annotation.SuppressLint
 import android.view.LayoutInflater
+import android.view.MotionEvent
 import android.view.View
 import android.view.ViewGroup
+import android.widget.ImageView
 import android.widget.TextView
 import androidx.recyclerview.widget.RecyclerView
+import java.util.Collections
 
-class RecyclerAdapter(private val items: MutableList<String>) :
+class RecyclerAdapter(private val items: MutableList<String>, private val showDragHandle: Boolean) :
     RecyclerView.Adapter<RecyclerAdapter.ViewHolder>() {
 
     var onItemClick: ((Int) -> Unit)? = null
+    var onItemsChanged: ((MutableList<String>) -> Unit)? = null
+    var onDragStart: ((RecyclerAdapter.ViewHolder) -> Unit)? = null
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerAdapter.ViewHolder {
         val view =
@@ -18,20 +24,39 @@ class RecyclerAdapter(private val items: MutableList<String>) :
         return vh
     }
 
+    @SuppressLint("ClickableViewAccessibility")
     override fun onBindViewHolder(holder: RecyclerAdapter.ViewHolder, position: Int) {
         val item = items[position]
 
         // sets the text to the textview from our itemHolder class
         holder.textView.text = item
+        if(showDragHandle) {
+            holder.dragHandle.visibility = View.VISIBLE
+            holder.dragHandle.setOnTouchListener {
+                    _, event ->
+                if (event.actionMasked == MotionEvent.ACTION_DOWN) {
+                    onDragStart?.invoke(holder)
+                }
+                return@setOnTouchListener true
+            }
+        }
     }
 
     override fun getItemCount(): Int {
         return items.size
     }
 
+    fun onItemMove(fromPosition: Int, toPosition: Int) {
+        // Swap items in your data list
+        Collections.swap(items, fromPosition, toPosition)
+        notifyItemMoved(fromPosition, toPosition)
+        onItemsChanged?.invoke(items)
+    }
+
 
     inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
         val textView: TextView = itemView.findViewById(R.id.textView)
+        val dragHandle: ImageView = itemView.findViewById(R.id.dragHandle)
 
         init {
             itemView.setOnClickListener {

app/src/main/res/drawable/ic_drag_handle_24.xml

@@ -0,0 +1,10 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="?attr/colorControlNormal">
+  <path
+      android:fillColor="@android:color/white"
+      android:pathData="M20,9H4v2h16V9zM4,15h16v-2H4v2z"/>
+</vector>

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

@@ -13,7 +13,18 @@
         android:layout_height="wrap_content"
         android:layout_marginStart="32dp"
         app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintEnd_toStartOf="@+id/dragHandle"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toTopOf="parent" />
+
+    <ImageView
+        android:id="@+id/dragHandle"
+        android:layout_width="32dp"
+        android:layout_height="32dp"
+        android:layout_marginEnd="32dp"
+        android:src="@drawable/ic_drag_handle_24"
+        android:visibility="gone"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintRight_toRightOf="parent"/>
 </androidx.constraintlayout.widget.ConstraintLayout>