Add support for circular focus in linear layouts

dpadrecyclerview/src/androidTest/kotlin/com/rubensousa/dpadrecyclerview/test/tests/focus/HorizontalCircularFocusTest.kt

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2022 Rúben Sousa
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.rubensousa.dpadrecyclerview.test.tests.focus
+
+import androidx.recyclerview.widget.RecyclerView
+import com.rubensousa.dpadrecyclerview.ChildAlignment
+import com.rubensousa.dpadrecyclerview.FocusableDirection
+import com.rubensousa.dpadrecyclerview.ParentAlignment
+import com.rubensousa.dpadrecyclerview.test.TestAdapterConfiguration
+import com.rubensousa.dpadrecyclerview.test.TestLayoutConfiguration
+import com.rubensousa.dpadrecyclerview.test.helpers.assertFocusAndSelection
+import com.rubensousa.dpadrecyclerview.test.helpers.onRecyclerView
+import com.rubensousa.dpadrecyclerview.test.helpers.waitForAdapterUpdate
+import com.rubensousa.dpadrecyclerview.test.helpers.waitForIdleScrollState
+import com.rubensousa.dpadrecyclerview.test.tests.DpadRecyclerViewTest
+import com.rubensousa.dpadrecyclerview.testing.KeyEvents
+import com.rubensousa.dpadrecyclerview.testing.rules.DisableIdleTimeoutRule
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+
+class HorizontalCircularFocusTest : DpadRecyclerViewTest() {
+
+    @get:Rule
+    val idleTimeoutRule = DisableIdleTimeoutRule()
+
+    private val numberOfItems = 3
+
+    override fun getDefaultLayoutConfiguration(): TestLayoutConfiguration {
+        return TestLayoutConfiguration(
+            spans = 1,
+            orientation = RecyclerView.HORIZONTAL,
+            parentAlignment = ParentAlignment(
+                edge = ParentAlignment.Edge.MIN_MAX
+            ),
+            childAlignment = ChildAlignment(offset = 0)
+        )
+    }
+
+    override fun getDefaultAdapterConfiguration(): TestAdapterConfiguration {
+        return super.getDefaultAdapterConfiguration().copy(
+            numberOfItems = numberOfItems,
+            itemLayoutId = com.rubensousa.dpadrecyclerview.testing.R.layout.dpadrecyclerview_test_item_horizontal
+        )
+    }
+
+    @Before
+    fun setup() {
+        launchFragment()
+        onRecyclerView("Set focusable direction") { recyclerView ->
+            recyclerView.setFocusableDirection(FocusableDirection.CIRCULAR)
+        }
+    }
+
+    @Test
+    fun testKeyUpMovesToLastPosition() {
+        // when
+        KeyEvents.pressLeft()
+        waitForIdleScrollState()
+
+        // then
+        assertFocusAndSelection(numberOfItems - 1)
+    }
+
+    @Test
+    fun testKeyDownMovesToFirstPosition() {
+        // when
+        KeyEvents.pressRight(numberOfItems)
+        waitForIdleScrollState()
+
+        // then
+        assertFocusAndSelection(0)
+    }
+
+    @Test
+    fun testCircularFocusDoesNotWorkIfLayoutIsFilled() {
+        // given
+        mutateAdapter { adapter ->
+            adapter.submitList(MutableList(10) { it })
+        }
+        waitForAdapterUpdate()
+
+        // when
+        KeyEvents.pressLeft()
+
+        // then
+        assertFocusAndSelection(position = 0)
+    }
+
+}

dpadrecyclerview/src/androidTest/kotlin/com/rubensousa/dpadrecyclerview/test/tests/focus/VerticalCircularFocusTest.kt

@@ -0,0 +1,103 @@
+/*
+ * Copyright 2022 Rúben Sousa
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.rubensousa.dpadrecyclerview.test.tests.focus
+
+import androidx.recyclerview.widget.RecyclerView
+import com.rubensousa.dpadrecyclerview.ChildAlignment
+import com.rubensousa.dpadrecyclerview.FocusableDirection
+import com.rubensousa.dpadrecyclerview.ParentAlignment
+import com.rubensousa.dpadrecyclerview.test.TestAdapterConfiguration
+import com.rubensousa.dpadrecyclerview.test.TestLayoutConfiguration
+import com.rubensousa.dpadrecyclerview.test.helpers.assertFocusAndSelection
+import com.rubensousa.dpadrecyclerview.test.helpers.onRecyclerView
+import com.rubensousa.dpadrecyclerview.test.helpers.waitForAdapterUpdate
+import com.rubensousa.dpadrecyclerview.test.helpers.waitForIdleScrollState
+import com.rubensousa.dpadrecyclerview.test.tests.DpadRecyclerViewTest
+import com.rubensousa.dpadrecyclerview.testing.KeyEvents
+import com.rubensousa.dpadrecyclerview.testing.rules.DisableIdleTimeoutRule
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+
+class VerticalCircularFocusTest : DpadRecyclerViewTest() {
+
+    @get:Rule
+    val idleTimeoutRule = DisableIdleTimeoutRule()
+
+    private val numberOfItems = 3
+
+    override fun getDefaultLayoutConfiguration(): TestLayoutConfiguration {
+        return TestLayoutConfiguration(
+            spans = 1,
+            orientation = RecyclerView.VERTICAL,
+            parentAlignment = ParentAlignment(
+                edge = ParentAlignment.Edge.MIN_MAX
+            ),
+            childAlignment = ChildAlignment(offset = 0)
+        )
+    }
+
+    override fun getDefaultAdapterConfiguration(): TestAdapterConfiguration {
+        return super.getDefaultAdapterConfiguration().copy(
+            numberOfItems = numberOfItems
+        )
+    }
+
+    @Before
+    fun setup() {
+        launchFragment()
+        onRecyclerView("Set focusable direction") { recyclerView ->
+            recyclerView.setFocusableDirection(FocusableDirection.CIRCULAR)
+        }
+    }
+
+    @Test
+    fun testKeyUpMovesToLastPosition() {
+        // when
+        KeyEvents.pressUp()
+        waitForIdleScrollState()
+
+        // then
+        assertFocusAndSelection(numberOfItems - 1)
+    }
+
+    @Test
+    fun testKeyDownMovesToFirstPosition() {
+        // when
+        KeyEvents.pressDown(numberOfItems)
+        waitForIdleScrollState()
+
+        // then
+        assertFocusAndSelection(0)
+    }
+
+    @Test
+    fun testCircularFocusDoesNotWorkIfLayoutIsFilled() {
+        // given
+        mutateAdapter { adapter ->
+            adapter.submitList(MutableList(10) { it })
+        }
+        waitForAdapterUpdate()
+
+        // when
+        KeyEvents.pressUp()
+
+        // then
+        assertFocusAndSelection(position = 0)
+    }
+
+}

dpadrecyclerview/src/main/java/com/rubensousa/dpadrecyclerview/layoutmanager/PivotLayoutManager.kt

@@ -75,7 +75,7 @@ class PivotLayoutManager(properties: Properties) : RecyclerView.LayoutManager(),
         this, configuration, layoutInfo, pivotSelector, scroller
     )
     private var hadFocusBeforeLayout = false
-    private var recyclerView: RecyclerView? = null
+    private var recyclerView: DpadRecyclerView? = null
     private var isScrollingFromTouchEvent = false
     internal var layoutCompletedListener: DpadRecyclerView.OnLayoutCompletedListener? = null
 

dpadrecyclerview/src/main/java/com/rubensousa/dpadrecyclerview/layoutmanager/focus/CircularFocusInterceptor.kt

@@ -17,20 +17,19 @@
 package com.rubensousa.dpadrecyclerview.layoutmanager.focus
 
 import android.view.View
-import androidx.recyclerview.widget.RecyclerView
+import com.rubensousa.dpadrecyclerview.DpadRecyclerView
 import com.rubensousa.dpadrecyclerview.FocusableDirection
 import com.rubensousa.dpadrecyclerview.layoutmanager.layout.LayoutInfo
 
 /**
  * Implementation for [FocusableDirection.CIRCULAR]
- * TODO: Add tests
  */
 internal class CircularFocusInterceptor(
     private val layoutInfo: LayoutInfo
 ) : FocusInterceptor {
 
     override fun findFocus(
-        recyclerView: RecyclerView,
+        recyclerView: DpadRecyclerView,
         focusedView: View,
         position: Int,
         direction: Int
@@ -40,10 +39,55 @@ internal class CircularFocusInterceptor(
             reverseLayout = layoutInfo.shouldReverseLayout(),
             direction = direction
         ) ?: return null
-        return findFocus(position, focusDirection)
+        return if (recyclerView.getSpanCount() == 1) {
+            findLinearFocus(position, focusDirection)
+        } else {
+            findGridFocus(position, focusDirection)
+        }
+    }
+
+    private fun findLinearFocus(position: Int, direction: FocusDirection): View? {
+        // We only support the main direction or if the layout is not looping
+        if (direction.isSecondary() || layoutInfo.isLoopingAllowed) {
+            return null
+        }
+        // We only allow circular focus for linear layouts if all the positions are displayed
+        if (!layoutInfo.hasCreatedFirstItem() || !layoutInfo.hasCreatedLastItem()) {
+            return null
+        }
+        val positionIncrement = layoutInfo.getPositionIncrement(
+            goingForward = direction == FocusDirection.NEXT_ROW
+                    || direction == FocusDirection.NEXT_COLUMN
+        )
+        val nextPosition = position + positionIncrement
+        return findNextFocusableView(
+            fromPosition = when (nextPosition) {
+                layoutInfo.getItemCount() -> 0
+                -1 -> layoutInfo.getItemCount() - 1
+                else -> nextPosition
+            },
+            limitPosition = position,
+            positionIncrement = positionIncrement
+        )
+    }
+
+    private fun findNextFocusableView(
+        fromPosition: Int,
+        limitPosition: Int,
+        positionIncrement: Int
+    ): View? {
+        var currentPosition = fromPosition
+        while (currentPosition != limitPosition) {
+            val view = layoutInfo.findViewByPosition(currentPosition)
+            if (view != null && layoutInfo.isViewFocusable(view)) {
+                return view
+            }
+            currentPosition += positionIncrement
+        }
+        return null
     }
 
-    private fun findFocus(position: Int, direction: FocusDirection): View? {
+    private fun findGridFocus(position: Int, direction: FocusDirection): View? {
         if (direction != FocusDirection.PREVIOUS_COLUMN && direction != FocusDirection.NEXT_COLUMN) {
             return null
         }

dpadrecyclerview/src/main/java/com/rubensousa/dpadrecyclerview/layoutmanager/focus/ContinuousFocusInterceptor.kt

@@ -17,20 +17,19 @@
 package com.rubensousa.dpadrecyclerview.layoutmanager.focus
 
 import android.view.View
-import androidx.recyclerview.widget.RecyclerView
+import com.rubensousa.dpadrecyclerview.DpadRecyclerView
 import com.rubensousa.dpadrecyclerview.FocusableDirection
 import com.rubensousa.dpadrecyclerview.layoutmanager.layout.LayoutInfo
 
 /**
  * Implementation for [FocusableDirection.CONTINUOUS]
- * TODO: Add tests
  */
 internal class ContinuousFocusInterceptor(
     private val layoutInfo: LayoutInfo,
 ) : FocusInterceptor {
 
     override fun findFocus(
-        recyclerView: RecyclerView,
+        recyclerView: DpadRecyclerView,
         focusedView: View,
         position: Int,
         direction: Int

dpadrecyclerview/src/main/java/com/rubensousa/dpadrecyclerview/layoutmanager/focus/DefaultFocusInterceptor.kt

@@ -18,7 +18,7 @@ package com.rubensousa.dpadrecyclerview.layoutmanager.focus
 
 import android.view.FocusFinder
 import android.view.View
-import androidx.recyclerview.widget.RecyclerView
+import com.rubensousa.dpadrecyclerview.DpadRecyclerView
 import com.rubensousa.dpadrecyclerview.FocusableDirection
 import com.rubensousa.dpadrecyclerview.layoutmanager.LayoutConfiguration
 import com.rubensousa.dpadrecyclerview.layoutmanager.layout.LayoutInfo
@@ -33,7 +33,7 @@ internal class DefaultFocusInterceptor(
 ) : FocusInterceptor {
 
     override fun findFocus(
-        recyclerView: RecyclerView,
+        recyclerView: DpadRecyclerView,
         focusedView: View,
         position: Int,
         direction: Int

dpadrecyclerview/src/main/java/com/rubensousa/dpadrecyclerview/layoutmanager/focus/FocusDirection.kt

@@ -24,6 +24,14 @@ internal enum class FocusDirection {
     PREVIOUS_COLUMN,
     NEXT_COLUMN;
 
+    fun isPrimary(): Boolean {
+        return this == PREVIOUS_ROW || this == NEXT_ROW
+    }
+
+    fun isSecondary(): Boolean {
+        return this == PREVIOUS_COLUMN || this == NEXT_COLUMN
+    }
+
     fun getScrollSign(reverseLayout: Boolean): Int {
         if (this == NEXT_COLUMN || this == PREVIOUS_COLUMN) {
             return 0
@@ -65,19 +73,23 @@ internal enum class FocusDirection {
                     View.FOCUS_LEFT -> {
                         if (reverseLayout) NEXT_COLUMN else PREVIOUS_COLUMN
                     }
+
                     View.FOCUS_RIGHT -> {
                         if (reverseLayout) PREVIOUS_COLUMN else NEXT_COLUMN
                     }
+
                     else -> null
                 }
             } else {
                 when (absoluteDirection) {
                     View.FOCUS_LEFT -> {
                         if (reverseLayout) NEXT_ROW else PREVIOUS_ROW
                     }
+
                     View.FOCUS_RIGHT -> {
                         if (reverseLayout) PREVIOUS_ROW else NEXT_ROW
                     }
+
                     View.FOCUS_UP -> if (reverseLayout) NEXT_COLUMN else PREVIOUS_COLUMN
                     View.FOCUS_DOWN -> if (reverseLayout) PREVIOUS_COLUMN else NEXT_COLUMN
                     else -> null