Merge pull request #1 from fumoboy007/master

Fix bug in `XBounds` calculation of minimum/maximum visible entry index.
JackMoseley2001 · Jul 30, 2022 · 2643deb · 2643deb
2 parents b38b8d4 + cfd7e8e
commit 2643deb
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Showing 2 changed files with 10 additions and 4 deletions.
diff --git a/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift
@@ -217,7 +217,7 @@ open class ChartDataSet: ChartBaseDataSet
         rounding: ChartDataSetRounding) -> Int
     {
         var closest = partitioningIndex { $0.x >= xValue }
-        guard closest < endIndex else { return rounding == .closest ? (endIndex-1) : -1 }
+        guard closest < endIndex else { return [.down, .closest].contains(rounding) ? (endIndex-1) : -1 }
 
         var closestXValue = self[closest].x
 

diff --git a/Source/Charts/Renderers/BarLineScatterCandleBubbleRenderer.swift b/Source/Charts/Renderers/BarLineScatterCandleBubbleRenderer.swift
@@ -102,9 +102,15 @@ open class BarLineScatterCandleBubbleRenderer: NSObject, DataRenderer
 
             let low = chart.lowestVisibleX
             let high = chart.highestVisibleX
-
-            let entryFrom = dataSet.entryForXValue(low, closestToY: .nan, rounding: .down)
-            let entryTo = dataSet.entryForXValue(high, closestToY: .nan, rounding: .up)
+
+            // First, try to find entries on the boundary of or outside of the visible range. Then, if there are none, try to find entries
+            // inside of the visible range.
+            //
+            // We want to allow and prioritize entries outside of the visible range because renderers may draw graphics in between entries.
+            // For example, a zoomed-in line graph should still show a line connecting the entry outside of the visible range with the entry
+            // inside of the visible range even if the line is only partially shown.
+            let entryFrom = dataSet.entryForXValue(low, closestToY: .nan, rounding: .down) ?? dataSet.entryForXValue(low, closestToY: .nan, rounding: .up)
+            let entryTo = dataSet.entryForXValue(high, closestToY: .nan, rounding: .up) ?? dataSet.entryForXValue(high, closestToY: .nan, rounding: .down)
 
             self.min = entryFrom == nil ? 0 : dataSet.entryIndex(entry: entryFrom!)
             self.max = entryTo == nil ? 0 : dataSet.entryIndex(entry: entryTo!)