diff --git a/app/src/main/kotlin/info/appdev/chartexample/LineChartTimeActivity.kt b/app/src/main/kotlin/info/appdev/chartexample/LineChartTimeActivity.kt
index 8c95cfe30..584843809 100644
--- a/app/src/main/kotlin/info/appdev/chartexample/LineChartTimeActivity.kt
+++ b/app/src/main/kotlin/info/appdev/chartexample/LineChartTimeActivity.kt
@@ -158,22 +158,22 @@ class LineChartTimeActivity : DemoBase(), OnSeekBarChangeListener {
             }
 
             R.id.actionToggleValues -> {
-                binding.chart1.data!!.dataSets.forEach { set ->
-                    set?.isDrawValues = !set.isDrawValues
+                binding.chart1.data?.dataSets?.forEach {
+                    it.isDrawValues = !it.isDrawValues
                 }
                 binding.chart1.invalidate()
             }
 
             R.id.actionToggleHighlight -> {
-                if (binding.chart1.data != null) {
-                    binding.chart1.data!!.isHighlightEnabled = !binding.chart1.data!!.isHighlightEnabled()
-                    binding.chart1.invalidate()
+                binding.chart1.data?.let {
+                    it.isHighlightEnabled = !it.isHighlightEnabled
                 }
+                binding.chart1.invalidate()
             }
 
             R.id.actionToggleFilled -> {
-                binding.chart1.data!!.dataSets.forEach { set ->
-                    set?.let {
+                binding.chart1.data?.dataSets?.forEach { set ->
+                    set.let {
                         if (set.isDrawFilledEnabled)
                             set.setDrawFilled(false)
                         else
@@ -184,20 +184,14 @@ class LineChartTimeActivity : DemoBase(), OnSeekBarChangeListener {
             }
 
             R.id.actionToggleCircles -> {
-                val sets = binding.chart1.data!!.dataSets
-
-                for (iSet in sets) {
-                    val set = iSet as LineDataSet
+                binding.chart1.data?.dataSets?.forEach { set ->
                     set.isDrawCirclesEnabled = !set.isDrawCirclesEnabled
                 }
                 binding.chart1.invalidate()
             }
 
             R.id.actionToggleCubic -> {
-                val sets = binding.chart1.data!!.dataSets
-
-                for (iSet in sets) {
-                    val set = iSet as LineDataSet
+                binding.chart1.data?.dataSets?.forEach { set ->
                     if (set.lineMode == LineDataSet.Mode.CUBIC_BEZIER)
                         set.lineMode = LineDataSet.Mode.LINEAR
                     else
@@ -207,10 +201,7 @@ class LineChartTimeActivity : DemoBase(), OnSeekBarChangeListener {
             }
 
             R.id.actionToggleStepped -> {
-                val sets = binding.chart1.data!!.dataSets
-
-                for (iSet in sets) {
-                    val set = iSet as LineDataSet
+                binding.chart1.data?.dataSets?.forEach { set ->
                     if (set.lineMode == LineDataSet.Mode.STEPPED)
                         set.lineMode = LineDataSet.Mode.LINEAR
                     else