WTA #71: Added accompanist for horizontal pager and modifier of mater…

…ial 3 version.

details/build.gradle.kts

@@ -7,4 +7,6 @@ android {
 }
 
 dependencies {
+    implementation("com.google.accompanist:accompanist-pager:0.29.0-alpha")
+    implementation("com.google.accompanist:accompanist-pager-indicators:0.29.0-alpha")
 }

details/src/main/java/com/jacob/wakatimeapp/details/ui/modiffiers/PagerTabIndicatorOffset.kt

@@ -0,0 +1,76 @@
+package com.jacob.wakatimeapp.details.ui.modiffiers
+
+import androidx.compose.material3.TabPosition
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.layout.layout
+import androidx.compose.ui.unit.Constraints
+import androidx.compose.ui.unit.lerp
+import com.google.accompanist.pager.ExperimentalPagerApi
+import com.google.accompanist.pager.PagerState
+
+/**
+ * [See Issue](https://github.com/google/accompanist/issues/1076)
+ * [Source](https://github.com/c5inco/Material3Pager/blob/main/app/src/main/java/com/c5inco/material3pager/PagerTab.kt)
+ */
+@ExperimentalPagerApi
+fun Modifier.pagerTabIndicatorOffset(
+    pagerState: PagerState,
+    tabPositions: List<TabPosition>,
+    pageIndexMapping: (Int) -> Int = { it },
+): Modifier = layout { measurable, constraints ->
+    if (tabPositions.isEmpty()) return@layout layout(constraints.maxWidth, 0) {}
+
+    val currentPage = minOf(tabPositions.lastIndex, pageIndexMapping(pagerState.currentPage))
+    val currentTab = tabPositions[currentPage]
+    val previousTab = tabPositions.getOrNull(currentPage - 1)
+    val nextTab = tabPositions.getOrNull(currentPage + 1)
+    val fraction = pagerState.currentPageOffset
+
+    val indicatorWidth = when {
+        fraction > 0 && nextTab != null -> lerp(
+            currentTab.width,
+            nextTab.width,
+            fraction
+        ).roundToPx()
+
+        fraction < 0 && previousTab != null -> lerp(
+            currentTab.width,
+            previousTab.width,
+            -fraction
+        ).roundToPx()
+
+        else -> currentTab.width.roundToPx()
+    }
+
+    val indicatorOffset = when {
+        fraction > 0 && nextTab != null -> lerp(
+            currentTab.left,
+            nextTab.left,
+            fraction
+        ).roundToPx()
+
+        fraction < 0 && previousTab != null -> lerp(
+            currentTab.left,
+            previousTab.left,
+            -fraction
+        ).roundToPx()
+
+        else -> currentTab.left.roundToPx()
+    }
+
+    val placeable = measurable.measure(
+        Constraints(
+            minWidth = indicatorWidth,
+            maxWidth = indicatorWidth,
+            minHeight = 0,
+            maxHeight = constraints.maxHeight
+        )
+    )
+
+    return@layout layout(constraints.maxWidth, maxOf(placeable.height, constraints.minHeight)) {
+        placeable.placeRelative(
+            indicatorOffset,
+            maxOf(constraints.minHeight - placeable.height, 0)
+        )
+    }
+}