refactor internal code

platacard · Nov 8, 2024 · eb401d8 · eb401d8
1 parent e2c70cd
commit eb401d8
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Showing 4 changed files with 31 additions and 37 deletions.
diff --git a/gradle.properties b/gradle.properties
@@ -1,4 +1,4 @@
-version=0.0.6
+version=0.0.7
 org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
 android.useAndroidX=true
 kotlin.code.style=official

diff --git a/pagerindicator/src/main/java/mx/platacard/pagerindicator/internal/Calculations.kt b/pagerindicator/src/main/java/mx/platacard/pagerindicator/internal/Calculations.kt
@@ -1,23 +1,22 @@
 package mx.platacard.pagerindicator.internal
 
-internal fun calculateDrawableDotIndices(
+internal fun calculateVisibleDotIndices(
     dotCount: Int,
     currentPage: Int,
     pageCount: Int,
 ): Pair<Int, Int> {
 
-    val onTheSidesDotCount = dotCount / 2
-
     val firstVisible: Int
     val lastVisible: Int
 
     if (currentPage < pageCount / 2) {
-        firstVisible = (currentPage - onTheSidesDotCount).coerceAtLeast(0)
-        lastVisible = (firstVisible + onTheSidesDotCount * 2)
+        firstVisible = (currentPage - dotCount / 2).coerceAtLeast(0)
+        lastVisible = (firstVisible + (dotCount - 1))
     } else {
-        lastVisible = (currentPage + onTheSidesDotCount).coerceAtMost(pageCount - 1)
-        firstVisible = (lastVisible - onTheSidesDotCount * 2)
+        lastVisible = (currentPage + dotCount / 2).coerceAtMost(pageCount - 1)
+        firstVisible = (lastVisible - (dotCount - 1))
     }
+
     return firstVisible to lastVisible
 }
 
@@ -30,7 +29,7 @@ internal fun calculateTargetDotSizeForPage(
 
     val onTheSidesDotCount = dotCount / 2
 
-    val (firstVisible, lastVisible) = calculateDrawableDotIndices(
+    val (firstVisible, lastVisible) = calculateVisibleDotIndices(
         dotCount = dotCount,
         currentPage = currentPage,
         pageCount = pageCount,

diff --git a/pagerindicator/src/main/java/mx/platacard/pagerindicator/internal/PagerIndicatorInternal.kt b/pagerindicator/src/main/java/mx/platacard/pagerindicator/internal/PagerIndicatorInternal.kt
@@ -51,7 +51,10 @@ internal fun PagerIndicatorInternal(
     onAfterDraw: DrawScope.() -> Unit = {},
 ) {
 
-    val adjustedDotCount = minOf(dotCount, pageCount)
+    val adjustedDotCount = when {
+        dotCount >= pageCount -> pageCount
+        else -> if (dotCount % 2 == 0) dotCount - 1 else dotCount
+    }
 
     val density = LocalDensity.current
 
@@ -94,28 +97,18 @@ internal fun PagerIndicatorInternal(
             .height(if (orientation == Horizontal) activeDotSize else mainAxisSize)
     ) {
 
-        val centerDot = pageCount / 2
-
         val pagerFraction = currentPageFraction.value
-        val pagesFromCenter = pagerFraction - centerDot
-
-        val additionalOffset = if (pageCount % 2 == 0 && adjustedDotCount != pageCount) 1 else 0
 
-        val mainAxisCenterX = if (orientation == Horizontal) center.x else center.y
-
-        val firstItemStart = mainAxisCenterX - (pageCount / 2f + additionalOffset) * dotSizePx -
-                ((pageCount - 1 - additionalOffset) / 2f) * spacePx
+        val itemsCount = (pagerFraction - adjustedDotCount / 2)
+            .coerceIn(
+                minimumValue = 0f,
+                maximumValue = pageCount - adjustedDotCount.toFloat(),
+            )
 
-        val scroll = when {
-            adjustedDotCount == pageCount -> 0f
-            else -> -pagesFromCenter.coerceIn(
-                minimumValue = (adjustedDotCount / 2 - centerDot).toFloat(),
-                maximumValue = (-adjustedDotCount / 2 + centerDot - additionalOffset).toFloat(),
-            ) * (dotSizePx + spacePx)
-        } + firstItemStart
+        val scroll = -itemsCount * (dotSizePx + spacePx)
 
-        val (firstVisible, lastVisible) = calculateDrawableDotIndices(
-            dotCount = dotCount,
+        val (firstVisible, lastVisible) = calculateVisibleDotIndices(
+            dotCount = adjustedDotCount,
             currentPage = pagerFraction.roundToInt(),
             pageCount = pageCount,
         ).let { (first, second) ->
@@ -189,7 +182,7 @@ internal fun Modifier.onDotClick(
 ): Modifier {
     return this.pointerInput(Unit) {
         detectTapGestures { offset ->
-            val (start, stop) = calculateDrawableDotIndices(
+            val (start, stop) = calculateVisibleDotIndices(
                 dotCount = dotCount,
                 currentPage = currentPageFraction.value.roundToInt(),
                 pageCount = pageCount,

diff --git a/sample/src/main/java/mx/platacard/pagerindicator/sample/SampleActivity.kt b/sample/src/main/java/mx/platacard/pagerindicator/sample/SampleActivity.kt
@@ -37,14 +37,16 @@ class SampleActivity : AppCompatActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContent {
-            Column(
-                modifier = Modifier
-                    .fillMaxSize(),
-                horizontalAlignment = Alignment.CenterHorizontally,
-                verticalArrangement = Arrangement.SpaceEvenly,
-            ) {
-                HorizontalPagerSample()
-                VerticalPagerSample()
+            Box {
+                Column(
+                    modifier = Modifier
+                        .fillMaxSize(),
+                    horizontalAlignment = Alignment.CenterHorizontally,
+                    verticalArrangement = Arrangement.SpaceEvenly,
+                ) {
+                    HorizontalPagerSample()
+                    VerticalPagerSample()
+                }
             }
         }
     }