MATLAB: Is the child of the parent of the Birds Eye Plot a line object

Automated Driving Toolboxaxesbirdseyegraphicshandlelineplot

I'm trying the following code:
BEP = birdsEyePlot('Xlimits', [0 220], 'Ylimits', [-200 200]); 
radarPlotter = detectionPlotter(BEP,'DisplayName','Radar detections'); 
plotDetection(radarPlotter,[[10 10]',[30 20]'])
BEP is a plot, hence as expected its parent is an axis: 
>>BEP.Parent 
ans = 
Axes (bepAxes) with properties: 
XLim: [0 220] 
YLim: [-200 200] 
XScale: 'linear' 
YScale: 'linear' 
GridLineStyle: '-' 
Position: [1×4 double] 
Units: 'normalized' 
>>BEP.Parent.Children 
ans = 
Line (bepDetectionPositions_Radar detections) with properties: 
Color: [0 0.447000000000000 0.741000000000000] 
LineStyle: 'none' 
LineWidth: 0.500000000000000 
Marker: 'o' 
MarkerSize: 6 
MarkerFaceColor: 'none' 
XData: [10 10] 
YData: [30 20] 
ZData: [1×0 double]
The children of its parent should be the BEP plot and the detection plot or am I misunderstanding something? 
I am thinking of using this approach to work with the created plots unless you see any reason not to do so: 
my_fig=BEP.Parent.Parent 
my_fig.Children(2).Children.LineStyle ='-';

Best Answer

It is important to note here that the Birds Eye Plot is a MATLAB class and not a graphics handle. Like with all plots, the "parent" of the Birds Eye Plot is a handle to the axes containing the plot. Therefore, when using the command - BEP.Parent.Children, the output will be the "children" of the axes handle which is a 'Line' object and not the BEP object as it is not a part of the handle graphics system.
In regards to your question about the approach, there seems to be nothing incorrect with the commands. Although a shorter route to specify the line style would be as follows:
my_Line = BEP.Parent.Children; 
my_Line.LineStyle ='-';
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