Add LazyColumnWithFooter to design system

config/detekt/detekt.yml

@@ -578,6 +578,8 @@ style:
     ignoreConstantDeclaration: true
     ignoreCompanionObjectPropertyDeclaration: true
     ignoreAnnotation: false
+    ignoreAnnotated:
+      - 'Preview'
     ignoreNamedArgument: true
     ignoreEnums: false
     ignoreRanges: false

core/ui/compose/designsystem/src/main/kotlin/app/k9mail/core/ui/compose/designsystem/template/LazyColumnWithFooter.kt

@@ -0,0 +1,86 @@
+package app.k9mail.core.ui.compose.designsystem.template
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.LazyListScope
+import androidx.compose.material.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.Density
+import androidx.compose.ui.unit.dp
+import app.k9mail.core.ui.compose.designsystem.atom.Surface
+import app.k9mail.core.ui.compose.theme.K9Theme
+
+/**
+ * The [LazyColumnWithFooter] composable creates a [LazyColumn] with a footer.
+ *
+ * @param modifier The modifier to be applied to the layout.
+ * @param verticalArrangement The vertical arrangement of the children.
+ * @param horizontalAlignment The horizontal alignment of the children.
+ * @param footer The footer to be displayed at the bottom of the [LazyColumn].
+ * @param content The content of the [LazyColumn].
+ */
+@Composable
+fun LazyColumnWithFooter(
+    modifier: Modifier = Modifier,
+    verticalArrangement: Arrangement.Vertical = Arrangement.Top,
+    horizontalAlignment: Alignment.Horizontal = Alignment.Start,
+    footer: @Composable () -> Unit = {},
+    content: LazyListScope.() -> Unit,
+) {
+    LazyColumn(
+        modifier = modifier,
+        verticalArrangement = verticalArrangementWithFooter(verticalArrangement),
+        horizontalAlignment = horizontalAlignment,
+    ) {
+        content()
+        item { footer() }
+    }
+}
+
+@Composable
+private fun verticalArrangementWithFooter(verticalArrangement: Arrangement.Vertical) = remember {
+    object : Arrangement.Vertical {
+        override fun Density.arrange(
+            totalSize: Int,
+            sizes: IntArray,
+            outPositions: IntArray,
+        ) {
+            val innerSizes = sizes.dropLast(1).toIntArray()
+            val footerSize = sizes.last()
+            val innerTotalSize = totalSize - footerSize
+
+            with(verticalArrangement) {
+                arrange(
+                    totalSize = innerTotalSize,
+                    sizes = innerSizes,
+                    outPositions = outPositions,
+                )
+            }
+
+            outPositions[outPositions.lastIndex] = totalSize - footerSize
+        }
+    }
+}
+
+@Composable
+@Preview
+internal fun LazyColumnWithFooterPreview() {
+    K9Theme {
+        Surface {
+            LazyColumnWithFooter(
+                modifier = Modifier.fillMaxSize(),
+                verticalArrangement = Arrangement.spacedBy(32.dp, Alignment.CenterVertically),
+                footer = { Text(text = "Footer") },
+            ) {
+                items(10) {
+                    Text(text = "Item $it")
+                }
+            }
+        }
+    }
+}