diff --git a/Source/Charts/Renderers/BarChartRenderer.swift b/Source/Charts/Renderers/BarChartRenderer.swift
index 842bcc67b9..138ee4f92d 100644
--- a/Source/Charts/Renderers/BarChartRenderer.swift
+++ b/Source/Charts/Renderers/BarChartRenderer.swift
@@ -25,7 +25,7 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
     
     @objc open weak var dataProvider: BarChartDataProvider?
     
-    @objc public init(dataProvider: BarChartDataProvider?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(dataProvider: BarChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/BubbleChartRenderer.swift b/Source/Charts/Renderers/BubbleChartRenderer.swift
index bf84a0eccf..cd727cf853 100644
--- a/Source/Charts/Renderers/BubbleChartRenderer.swift
+++ b/Source/Charts/Renderers/BubbleChartRenderer.swift
@@ -21,7 +21,7 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
 {
     @objc open weak var dataProvider: BubbleChartDataProvider?
     
-    @objc public init(dataProvider: BubbleChartDataProvider?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(dataProvider: BubbleChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/CandleStickChartRenderer.swift b/Source/Charts/Renderers/CandleStickChartRenderer.swift
index 01dc0e8b45..2a3eddcdec 100644
--- a/Source/Charts/Renderers/CandleStickChartRenderer.swift
+++ b/Source/Charts/Renderers/CandleStickChartRenderer.swift
@@ -21,7 +21,7 @@ open class CandleStickChartRenderer: LineScatterCandleRadarRenderer
 {
     @objc open weak var dataProvider: CandleChartDataProvider?
     
-    @objc public init(dataProvider: CandleChartDataProvider?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(dataProvider: CandleChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/CombinedChartRenderer.swift b/Source/Charts/Renderers/CombinedChartRenderer.swift
index 7fe5106bf2..e36853ac6b 100644
--- a/Source/Charts/Renderers/CombinedChartRenderer.swift
+++ b/Source/Charts/Renderers/CombinedChartRenderer.swift
@@ -26,7 +26,7 @@ open class CombinedChartRenderer: DataRenderer
     
     internal var _drawOrder: [CombinedChartView.DrawOrder] = [.bar, .bubble, .line, .candle, .scatter]
     
-    @objc public init(chart: CombinedChartView?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(chart: CombinedChartView, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/HorizontalBarChartRenderer.swift b/Source/Charts/Renderers/HorizontalBarChartRenderer.swift
index 9f40cabb46..00e1f3d86a 100644
--- a/Source/Charts/Renderers/HorizontalBarChartRenderer.swift
+++ b/Source/Charts/Renderers/HorizontalBarChartRenderer.swift
@@ -24,7 +24,7 @@ open class HorizontalBarChartRenderer: BarChartRenderer
         var rects = [CGRect]()
     }
     
-    public override init(dataProvider: BarChartDataProvider?, animator: Animator, viewPortHandler: ViewPortHandler)
+    public override init(dataProvider: BarChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(dataProvider: dataProvider, animator: animator, viewPortHandler: viewPortHandler)
     }
diff --git a/Source/Charts/Renderers/LineChartRenderer.swift b/Source/Charts/Renderers/LineChartRenderer.swift
index 2209ac0f62..b1c2b816f2 100644
--- a/Source/Charts/Renderers/LineChartRenderer.swift
+++ b/Source/Charts/Renderers/LineChartRenderer.swift
@@ -21,7 +21,7 @@ open class LineChartRenderer: LineRadarRenderer
 {
     @objc open weak var dataProvider: LineChartDataProvider?
     
-    @objc public init(dataProvider: LineChartDataProvider?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(dataProvider: LineChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/PieChartRenderer.swift b/Source/Charts/Renderers/PieChartRenderer.swift
index b0f5a6d318..23bc60b515 100644
--- a/Source/Charts/Renderers/PieChartRenderer.swift
+++ b/Source/Charts/Renderers/PieChartRenderer.swift
@@ -21,7 +21,7 @@ open class PieChartRenderer: DataRenderer
 {
     @objc open weak var chart: PieChartView?
     
-    @objc public init(chart: PieChartView?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(chart: PieChartView, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/RadarChartRenderer.swift b/Source/Charts/Renderers/RadarChartRenderer.swift
index d0b63bcf80..d9bd19d3d2 100644
--- a/Source/Charts/Renderers/RadarChartRenderer.swift
+++ b/Source/Charts/Renderers/RadarChartRenderer.swift
@@ -21,7 +21,7 @@ open class RadarChartRenderer: LineRadarRenderer
 {
     @objc open weak var chart: RadarChartView?
 
-    @objc public init(chart: RadarChartView?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(chart: RadarChartView, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/ScatterChartRenderer.swift b/Source/Charts/Renderers/ScatterChartRenderer.swift
index 99f74fd6f7..d187eb0023 100644
--- a/Source/Charts/Renderers/ScatterChartRenderer.swift
+++ b/Source/Charts/Renderers/ScatterChartRenderer.swift
@@ -21,7 +21,7 @@ open class ScatterChartRenderer: LineScatterCandleRadarRenderer
 {
     @objc open weak var dataProvider: ScatterChartDataProvider?
     
-    @objc public init(dataProvider: ScatterChartDataProvider?, animator: Animator, viewPortHandler: ViewPortHandler)
+    @objc public init(dataProvider: ScatterChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
diff --git a/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift b/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift
index d46b67cf4f..81e9c2cd6e 100644
--- a/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift
+++ b/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift
@@ -20,7 +20,7 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
 {
     @objc internal var chart: BarChartView?
     
-    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, transformer: Transformer?, chart: BarChartView?)
+    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, transformer: Transformer?, chart: BarChartView)
     {
         super.init(viewPortHandler: viewPortHandler, xAxis: xAxis, transformer: transformer)
         
diff --git a/Source/Charts/Renderers/XAxisRendererRadarChart.swift b/Source/Charts/Renderers/XAxisRendererRadarChart.swift
index be72585763..8b98791c23 100644
--- a/Source/Charts/Renderers/XAxisRendererRadarChart.swift
+++ b/Source/Charts/Renderers/XAxisRendererRadarChart.swift
@@ -20,7 +20,7 @@ open class XAxisRendererRadarChart: XAxisRenderer
 {
     @objc open weak var chart: RadarChartView?
     
-    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, chart: RadarChartView?)
+    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, chart: RadarChartView)
     {
         super.init(viewPortHandler: viewPortHandler, xAxis: xAxis, transformer: nil)
         
diff --git a/Source/Charts/Renderers/YAxisRendererRadarChart.swift b/Source/Charts/Renderers/YAxisRendererRadarChart.swift
index f9311adc72..e34b7d8009 100644
--- a/Source/Charts/Renderers/YAxisRendererRadarChart.swift
+++ b/Source/Charts/Renderers/YAxisRendererRadarChart.swift
@@ -20,7 +20,7 @@ open class YAxisRendererRadarChart: YAxisRenderer
 {
     fileprivate weak var chart: RadarChartView?
     
-    @objc public init(viewPortHandler: ViewPortHandler, yAxis: YAxis?, chart: RadarChartView?)
+    @objc public init(viewPortHandler: ViewPortHandler, yAxis: YAxis?, chart: RadarChartView)
     {
         super.init(viewPortHandler: viewPortHandler, yAxis: yAxis, transformer: nil)