Added inner AccessHelper class for talkback functional

app/src/main/kotlin/com/simplemobiletools/keyboard/views/MyKeyboardView.kt

@@ -10,6 +10,7 @@ import android.content.Intent
 import android.graphics.*
 import android.graphics.Paint.Align
 import android.graphics.drawable.*
+import android.os.Bundle
 import android.os.Handler
 import android.os.Looper
 import android.os.Message
@@ -24,6 +25,9 @@ import android.widget.PopupWindow
 import android.widget.TextView
 import androidx.core.animation.doOnEnd
 import androidx.core.animation.doOnStart
+import androidx.core.view.ViewCompat
+import androidx.core.view.accessibility.AccessibilityNodeInfoCompat
+import androidx.customview.widget.ExploreByTouchHelper
 import androidx.emoji2.text.EmojiCompat
 import androidx.emoji2.text.EmojiCompat.EMOJI_SUPPORTED
 import com.simplemobiletools.commons.extensions.*
@@ -95,6 +99,83 @@ class MyKeyboardView @JvmOverloads constructor(context: Context, attrs: Attribut
         fun reloadKeyboard()
     }
 
+    override fun dispatchHoverEvent(event: MotionEvent): Boolean {
+        return if (accessHelper.dispatchHoverEvent(event)) {
+            true
+        } else {
+            super.dispatchHoverEvent(event)
+        }
+    }
+
+    private val accessHelper = AccessHelper()
+
+
+    inner class AccessHelper() : ExploreByTouchHelper(this) {
+
+        /**
+         * We need to populate the list with the IDs of all of the visible virtual views (the intervals in the chart).
+         * In our case, all keys are always visible, so we’ll return a list of all IDs.
+         */
+        override fun getVisibleVirtualViews(virtualViewIds: MutableList<Int>) {
+            val keysSize = mKeyboard?.mKeys?.size ?: 0
+            for (i in 0 until keysSize) {
+                virtualViewIds.add(i)
+            }
+        }
+
+        /**
+         * For this function, we need to return the ID of the virtual view that’s under the x, y position,
+         * or ExploreByTouchHelper.HOST_ID if there’s no item at those coordinates.
+         */
+        override fun getVirtualViewAt(x: Float, y: Float): Int {
+            mKeyboard?.mKeys?.filterNotNull()?.let { keyList ->
+                val rects = keyList.map {
+                    Rect(it.x, it.y, it.x + it.width, it.y + it.height)
+                }
+                rects.firstOrNull { it.contains(x.toInt(), y.toInt()) }?.let { exactRect ->
+                    val exactIndexKey = rects.indexOf(exactRect)
+                    return exactIndexKey
+                } ?: return HOST_ID
+            }
+            return HOST_ID
+        }
+
+        /**
+         * This is where we provide all the metadata for our virtual view.
+         * We need to set the content description (or text, if it’s presented visually) and set the bounds in parent.
+         */
+        override fun onPopulateNodeForVirtualView(virtualViewId: Int, node: AccessibilityNodeInfoCompat) {
+            node.className = MyKeyboardView::class.simpleName
+            val key = mKeyboard?.mKeys?.get(virtualViewId)
+            node.contentDescription = key?.label ?: "keyboard key"
+            val bounds = updateBoundsForInterval(virtualViewId)
+            node.setBoundsInParent(bounds)
+        }
+
+        /**
+         * We need to set the content description (or text, if it’s presented visually) and set the bounds in parent.
+         * The bounds in the parent should match the logic in the onDraw() function.
+         */
+        private fun updateBoundsForInterval(index: Int): Rect {
+            val keys = mKeyboard?.mKeys ?: return Rect()
+            val key = keys[index]!!
+            return Rect().apply {
+                left = key.x
+                top = key.y
+                right = key.x + key.width
+                bottom = key.y + key.height
+            }
+        }
+
+        override fun onPerformActionForVirtualView(virtualViewId: Int, action: Int, arguments: Bundle?): Boolean {
+            return false
+        }
+    }
+
+    init {
+        ViewCompat.setAccessibilityDelegate(this, accessHelper)
+    }
+
     private var mKeyboard: MyKeyboard? = null
     private var mCurrentKeyIndex: Int = NOT_A_KEY