Bug/ml fixes

Source/Meadow.Foundation.Libraries_and_Frameworks/Graphics.MicroLayout/Driver/Charts/HistogramChart.cs

@@ -171,7 +171,14 @@ private void DrawSeries(MicroGraphics graphics, List<HistogramChartSeries> serie
                 var barHeight = (int)(heightScale * pair.Y);
 
                 // make sure we don't draw off-chart for over-scale values
-                if (barHeight > ChartAreaHeight) { barHeight = ChartAreaHeight; }
+                if (barHeight > ChartAreaHeight)
+                {
+                    barHeight = ChartAreaHeight;
+                }
+                if ((x < ChartAreaLeft) || (x > ChartAreaLeft + ChartAreaWidth))
+                {
+                    continue;
+                }
 
                 DrawValueBar(
                     graphics,

Source/Meadow.Foundation.Libraries_and_Frameworks/Graphics.MicroLayout/Driver/Controls/Box.cs

@@ -6,11 +6,16 @@
 public class Box : ThemedControl
 {
     private Color _foreColor;
+    private bool _isFilled = true;
 
     /// <summary>
     /// Gets or sets a value indicating whether the display box is filled with the foreground color.
     /// </summary>
-    public bool IsFilled { get; set; } = true;
+    public bool IsFilled
+    {
+        get => _isFilled;
+        set => SetInvalidatingProperty(ref _isFilled, value);
+    }
 
     /// <summary>
     /// Initializes a new instance of the <see cref="Box"/> class with the specified dimensions.

Source/Meadow.Foundation.Libraries_and_Frameworks/Graphics.MicroLayout/Driver/ControlsCollection.cs

@@ -77,6 +77,8 @@ public void Add(params IControl[] controls)
         {
             foreach (var control in controls)
             {
+                if (control is null) continue;
+
                 control.Parent = _container;
                 _controls.Add(control);
             }