feat: make boards drawer width adaptive by screen class

app/src/androidTest/java/space/hackenslacker/kanbn4droid/app/BoardsFlowTest.kt

@@ -281,7 +281,7 @@ class BoardsFlowTest {
     }
 
     @Test
-    fun drawerWidthNeverExceedsOneThirdOfScreen() {
+    fun drawerWidthIsAdaptiveForSmallAndLargeScreens() {
         MainActivity.dependencies.apiClientFactory = {
             FakeBoardsApiClient(
                 boards = mutableListOf(BoardSummary("1", "Alpha")),
@@ -292,9 +292,19 @@ class BoardsFlowTest {
         val scenario = ActivityScenario.launch(BoardsActivity::class.java)
 
         scenario.onActivity { activity ->
+            val drawerLayout = activity.findViewById<DrawerLayout>(R.id.boardsDrawerLayout)
             val drawerContent = activity.findViewById<View>(R.id.boardsDrawerContent)
-            val displayWidthPx = activity.resources.displayMetrics.widthPixels
-            assertTrue(drawerContent.layoutParams.width <= displayWidthPx / 3)
+            val resources = activity.resources
+            val breakpointSwDp = resources.getInteger(R.integer.boards_drawer_tablet_breakpoint_sw_dp)
+            val maxWidthPx = resources.getDimensionPixelSize(R.dimen.boards_drawer_max_width)
+            val isSmallScreen = resources.configuration.smallestScreenWidthDp < breakpointSwDp
+            val expectedWidth = if (isSmallScreen) {
+                drawerLayout.width
+            } else {
+                minOf((drawerLayout.width * 2) / 3, maxWidthPx)
+            }
+
+            assertEquals(expectedWidth, drawerContent.layoutParams.width)
         }
     }
 

app/src/main/java/space/hackenslacker/kanbn4droid/app/BoardsActivity.kt

@@ -13,6 +13,7 @@ import androidx.activity.viewModels
 import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.GravityCompat
+import androidx.core.view.doOnLayout
 import androidx.drawerlayout.widget.DrawerLayout
 import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.LinearLayoutManager
@@ -40,6 +41,7 @@ import space.hackenslacker.kanbn4droid.app.boards.BoardsRepository
 import space.hackenslacker.kanbn4droid.app.boards.BoardsUiEvent
 import space.hackenslacker.kanbn4droid.app.boards.BoardsUiState
 import space.hackenslacker.kanbn4droid.app.boards.BoardsViewModel
+import space.hackenslacker.kanbn4droid.app.boards.BoardsDrawerWidthCalculator
 import space.hackenslacker.kanbn4droid.app.boards.DrawerDataErrorCode
 import space.hackenslacker.kanbn4droid.app.boarddetail.BoardDetailActivity
 import space.hackenslacker.kanbn4droid.app.settings.SettingsDialogFragment
@@ -284,11 +286,18 @@ class BoardsActivity : AppCompatActivity() {
     }
 
     private fun applyDrawerWidth() {
-        val maxWidthPx = resources.getDimensionPixelSize(R.dimen.boards_drawer_max_width)
-        val displayWidthPx = resources.displayMetrics.widthPixels
-        val computedWidth = minOf(displayWidthPx / 3, maxWidthPx)
-        drawerContent.layoutParams = drawerContent.layoutParams.apply {
-            width = computedWidth
+        drawerLayout.doOnLayout {
+            val maxWidthPx = resources.getDimensionPixelSize(R.dimen.boards_drawer_max_width)
+            val breakpointSwDp = resources.getInteger(R.integer.boards_drawer_tablet_breakpoint_sw_dp)
+            val computedWidth = BoardsDrawerWidthCalculator.computeWidth(
+                smallestScreenWidthDp = resources.configuration.smallestScreenWidthDp,
+                tabletBreakpointSwDp = breakpointSwDp,
+                windowWidthPx = drawerLayout.width,
+                maxWidthPx = maxWidthPx,
+            )
+            drawerContent.layoutParams = drawerContent.layoutParams.apply {
+                width = computedWidth
+            }
         }
     }
 

app/src/main/java/space/hackenslacker/kanbn4droid/app/boards/BoardsDrawerWidthCalculator.kt

@@ -0,0 +1,15 @@
+package space.hackenslacker.kanbn4droid.app.boards
+
+object BoardsDrawerWidthCalculator {
+    fun computeWidth(
+        smallestScreenWidthDp: Int,
+        tabletBreakpointSwDp: Int,
+        windowWidthPx: Int,
+        maxWidthPx: Int,
+    ): Int {
+        if (smallestScreenWidthDp < tabletBreakpointSwDp) {
+            return windowWidthPx
+        }
+        return minOf((windowWidthPx * 2) / 3, maxWidthPx)
+    }
+}

app/src/main/res/values/integers.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <integer name="boards_drawer_tablet_breakpoint_sw_dp">600</integer>
+</resources>

app/src/test/java/space/hackenslacker/kanbn4droid/app/boards/BoardsDrawerWidthCalculatorTest.kt

@@ -0,0 +1,78 @@
+package space.hackenslacker.kanbn4droid.app.boards
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class BoardsDrawerWidthCalculatorTest {
+    @Test
+    fun smallScreenUsesFullWidth() {
+        val result = BoardsDrawerWidthCalculator.computeWidth(
+            smallestScreenWidthDp = 411,
+            tabletBreakpointSwDp = 600,
+            windowWidthPx = 1080,
+            maxWidthPx = 900,
+        )
+
+        assertEquals(1080, result)
+    }
+
+    @Test
+    fun smallScreenUsesFullWidthIgnoringCap() {
+        val result = BoardsDrawerWidthCalculator.computeWidth(
+            smallestScreenWidthDp = 411,
+            tabletBreakpointSwDp = 600,
+            windowWidthPx = 1080,
+            maxWidthPx = 320,
+        )
+
+        assertEquals(1080, result)
+    }
+
+    @Test
+    fun boundaryAtBreakpointUsesLargeRule() {
+        val result = BoardsDrawerWidthCalculator.computeWidth(
+            smallestScreenWidthDp = 600,
+            tabletBreakpointSwDp = 600,
+            windowWidthPx = 1000,
+            maxWidthPx = 700,
+        )
+
+        assertEquals(666, result)
+    }
+
+    @Test
+    fun largeScreenAppliesTwoThirdsWithCap() {
+        val result = BoardsDrawerWidthCalculator.computeWidth(
+            smallestScreenWidthDp = 1024,
+            tabletBreakpointSwDp = 600,
+            windowWidthPx = 1024,
+            maxWidthPx = 700,
+        )
+
+        assertEquals(682, result)
+    }
+
+    @Test
+    fun boundaryBelowBreakpointUsesSmallRule() {
+        val result = BoardsDrawerWidthCalculator.computeWidth(
+            smallestScreenWidthDp = 599,
+            tabletBreakpointSwDp = 600,
+            windowWidthPx = 1000,
+            maxWidthPx = 700,
+        )
+
+        assertEquals(1000, result)
+    }
+
+    @Test
+    fun largeScreenUsesCapWhenTwoThirdsExceedsCap() {
+        val result = BoardsDrawerWidthCalculator.computeWidth(
+            smallestScreenWidthDp = 840,
+            tabletBreakpointSwDp = 600,
+            windowWidthPx = 840,
+            maxWidthPx = 560,
+        )
+
+        assertEquals(560, result)
+    }
+}