charts - Retrieving PlotRange from BarChart

Consider the following data:

data1={73.9377, 54.4122, 53.0826, 24.1936};
data2={76.828, 49.1673, 45.7883, 18.9015};

I defined my own BarChart as follows:

MyBarCharts[list_]:= 
 BarChart[
   list,

   Frame -> {{True, None}, {True, None}}
 ]

When applying MyBarCharts to data1 and data2 I get (not really surprising) two different (with regard to the coordinate system) plots. Now I would like to have for both plots the exact same coordinate system. I know that with Histogram it works as follows:

Histogram[
data2,
PlotRange -> Part[PlotRange /. Options[Histogram[
                                       data1,
                                       PlotRange -> Automatic
                                       ],PlotRange], 2],

Frame -> {{True, None}, {True, None}}]

But the implementation of that approach in MyBarCharts does not give the desired result. Has anyone an idea?

Answer

Extracting the PlotRange from a BarChart is not as straightforward as it should be. If no PlotRange is specified in creating the chart, then Options will return PlotRange -> All and AbsoluteOptions will return PlotRange -> {{0., 1.}, {0., 1.}

bc = BarChart[{1, 2, 3, 4}];

Options[bc, PlotRange]
(* {PlotRange -> All} *)


AbsoluteOptions[bc, PlotRange]
(* {PlotRange -> {{0., 1.}, {0., 1.}}} *)

The incorrect result from AbsoluteOptions appears to be related to the presence of dynamic objects in the graphics expression (i.e. the bars with their mouseover effects) . I don't know why this causes AbsoluteOptions to go wrong, but a workaround is to replace the dynamic bars with straighforward rectangles, allowing AbsoluteOptions to extract the correct PlotRange. Thus, a replacement for AbsoluteOptions for BarCharts is:

barChartOptions[chart_, opts___] := 
 AbsoluteOptions[chart /. 
  Tooltip[StatusArea[RawBoxes[DynamicBox[{_, RectangleBox[data__]}]], _], _] :> 
    Rectangle[data], opts]

barChartOptions[bc, PlotRange]

(* {PlotRange -> {{0.545455, 4.45455}, {0., 4.}}} *)