Let the last row of FAB lists scroll above the button

app/src/main/kotlin/com/nativeapptemplate/nativeapptemplatefree/ui/common/FabClearance.kt

@@ -0,0 +1,20 @@
+package com.nativeapptemplate.nativeapptemplatefree.ui.common
+
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.padding
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+
+/**
+ * Space below the last row of a list on a screen with a floating action button, so the last row
+ * (and the actions it reveals when swiped) can scroll above the button instead of staying under it.
+ * The tallest button is SubmitFab (64.dp; FloatingActionButton is 56.dp), the Scaffold places it
+ * 16.dp above the bottom, and 16.dp more keeps the row clear of it: 64 + 16 + 16 = 96.
+ */
+val FabClearance = 96.dp
+
+/** The lists' 24.dp margin, without the bottom: the bottom is [fabClearingContentPadding]. */
+val fabListModifier: Modifier = Modifier.padding(start = 24.dp, top = 24.dp, end = 24.dp)
+
+/** Content padding for a list on a screen with a floating action button; see [FabClearance]. */
+val fabClearingContentPadding = PaddingValues(bottom = FabClearance)

app/src/main/kotlin/com/nativeapptemplate/nativeapptemplatefree/ui/shop_settings/item_tag_list/ItemTagListView.kt

@@ -55,6 +55,8 @@ import com.nativeapptemplate.nativeapptemplatefree.ui.common.LoadingView
 import com.nativeapptemplate.nativeapptemplatefree.ui.common.MainButtonView
 import com.nativeapptemplate.nativeapptemplatefree.ui.common.SnackbarMessageEffect
 import com.nativeapptemplate.nativeapptemplatefree.ui.common.SwipeableItemWithActions
+import com.nativeapptemplate.nativeapptemplatefree.ui.common.fabClearingContentPadding
+import com.nativeapptemplate.nativeapptemplatefree.ui.common.fabListModifier
 
 @Composable
 internal fun ItemTagListView(
@@ -195,7 +197,8 @@ private fun ItemTagListContentView(
       ) {
         LazyColumn(
           state = listState,
-          modifier = Modifier.padding(24.dp),
+          modifier = fabListModifier,
+          contentPadding = fabClearingContentPadding,
         ) {
           item {
             Text(

app/src/main/kotlin/com/nativeapptemplate/nativeapptemplatefree/ui/shops/ShopListView.kt

@@ -48,6 +48,8 @@ import com.nativeapptemplate.nativeapptemplatefree.ui.common.ErrorView
 import com.nativeapptemplate.nativeapptemplatefree.ui.common.LoadingView
 import com.nativeapptemplate.nativeapptemplatefree.ui.common.MainButtonView
 import com.nativeapptemplate.nativeapptemplatefree.ui.common.SnackbarMessageEffect
+import com.nativeapptemplate.nativeapptemplatefree.ui.common.fabClearingContentPadding
+import com.nativeapptemplate.nativeapptemplatefree.ui.common.fabListModifier
 
 @Composable
 internal fun ShopListView(
@@ -164,7 +166,8 @@ private fun ShopListContentView(
           .padding(padding),
       ) {
         LazyColumn(
-          Modifier.padding(24.dp),
+          modifier = fabListModifier,
+          contentPadding = fabClearingContentPadding,
         ) {
           item {
             if (!uiState.didShowTapShopBelowTip) {

app/src/test/kotlin/com/nativeapptemplate/nativeapptemplatefree/ui/shop_settings/item_tag_list/ItemTagListViewModelTest.kt

@@ -2,14 +2,17 @@ package com.nativeapptemplate.nativeapptemplatefree.ui.shop_settings.item_tag_li
 
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
+import androidx.compose.ui.test.getUnclippedBoundsInRoot
 import androidx.compose.ui.test.hasScrollToIndexAction
 import androidx.compose.ui.test.hasScrollToKeyAction
 import androidx.compose.ui.test.junit4.v2.createComposeRule
+import androidx.compose.ui.test.onNodeWithContentDescription
 import androidx.compose.ui.test.onNodeWithText
 import androidx.compose.ui.test.performScrollToIndex
 import androidx.compose.ui.test.performScrollToKey
 import androidx.lifecycle.SavedStateHandle
 import androidx.navigation.testing.invoke
+import com.nativeapptemplate.nativeapptemplatefree.R
 import com.nativeapptemplate.nativeapptemplatefree.data.item_tag.ItemTagRepository
 import com.nativeapptemplate.nativeapptemplatefree.model.Attributes
 import com.nativeapptemplate.nativeapptemplatefree.model.Data
@@ -36,6 +39,7 @@ import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.robolectric.RobolectricTestRunner
+import org.robolectric.RuntimeEnvironment
 
 /**
  * These tests use Robolectric because the subject under test (the ViewModel) uses
@@ -298,6 +302,35 @@ class ItemTagListViewModelTest {
     composeTestRule.onNodeWithText("A007").assertExists()
   }
 
+  // The last row (and the Delete button its swipe reveals) must be able to scroll above the "+"
+  // button; without bottom content padding the list ends behind the button and the row stays under it.
+  @Test
+  fun lastRow_scrollsAboveTheAddButton() {
+    // 20 tags on one page: longer than the screen, so the list scrolls.
+    itemTagRepository.itemTagsForPage = { page -> pagedItemTags(page = page ?: 1, totalPages = 1, perPage = 20) }
+    shopRepository.sendShop(testInputShop)
+    composeTestRule.setContent {
+      val uiState by viewModel.uiState.collectAsState()
+      ItemTagListView(
+        viewModel = viewModel,
+        uiState = uiState,
+        onItemClick = {},
+        onAddItemTagClick = {},
+        onBackClick = {},
+      )
+    }
+    composeTestRule.runOnIdle { viewModel.reload() }
+
+    // Scrolling to the last tag scrolls the list to its end. pagedItemTags names tag 20 "A020".
+    composeTestRule.onNode(hasScrollToKeyAction()).performScrollToKey("item-tag-20")
+    val context = RuntimeEnvironment.getApplication()
+    val lastRowBottom = composeTestRule.onNodeWithText("A020").getUnclippedBoundsInRoot().bottom
+    val addButtonTop = composeTestRule.onNodeWithContentDescription(context.getString(R.string.label_add_item_tag))
+      .getUnclippedBoundsInRoot().top
+
+    assertTrue("last row ends at $lastRowBottom, the add button starts at $addButtonTop", lastRowBottom <= addButtonTop)
+  }
+
   // The API rejects it: the coded error is shown, the spinner stops, and the list stays.
   @Test
   fun deleteItemTag_whenTheApiRejectsIt_showsTheErrorAndKeepsTheList() = runTest {