Mathematica: Can I match the BarChart Legend to th

问题:

I would like to have the vertical arrangement of colors in stacked bars match the arrangement of colors in the chart legend. But no matter what I try, they don't match. Here's the situation

BarChart[{{5, 37, 56}, {22, 49, 28}, {31, 60, 10}},
   ChartLayout -> "Percentile",
   ChartLegends -> Placed[{"1-Volume", "2-Area", "3-Length"}, Right],
   ChartLabels -> {{"Before", "During", "After"}, None}]

In the real-world example the legend has quite a few more entries (6), so it would be nice if the order of the legend colors matched the order in the bars. I realize that I could set the ChartLegends to display at Bottom, but doesn't look good given the many legend entries.

Also, reversing the Legends list does not work as desired. The text of the legends was re-ordered, but the colors were not reordered (see below), so the legend captions no longer match the data in the chart.

Changing the order of the data (or the data and the legend items) does not work either.

Any suggestions?

回答1:

BarChart[{{5, 37, 56}, {22, 49, 28}, {31, 60, 10}}, 
  ChartLayout -> "Percentile", 
  ChartLegends -> {"1-Volume", "2-Area", "3-Length"}, 
  ChartLabels -> {{"Before", "During", "After"}, None}] /. 
 Column[List[a : Grid[List[___]] ..]] :> Column[Reverse@List@a]

Edit

Remember to use FullForm when you want to mess up with Graphics/Chart/Plot internals

回答2:

Building on the nice answer given by Belisarius, an alternative method using Part

bc[[2,1,1,1]]= Reverse@bc[[2,1,1,1]];bc

This may be inferred from FullForm and

Position[bc, #, Infinity]& /@ {Framed[___],
Column[___],List[___,"1-Volume",___]}

or from any one of these, perhaps, and trial-and-error.

Although not part of the question, Simon's trick (see here) may be used to further manipulate the legend.

bc/.Labeled[g_,Framed[leg_],pos_]:>
Labeled[g,Framed[leg,FrameStyle->Orange,RoundingRadius->10,
Background->LightYellow],pos]

for example, gives the following:

Part may also be used to remove the frame around the legend (see this question) but Simon's method is much more versatile.

bc[[2]]=bc[[2,1]];bc

回答3:

You can use LegendContainer for this.

SetOptions[Legending`GridLegend, 
  Legending`LegendContainer -> (Framed@MapAt[Reverse, #, {1, 1}] &)];

BarChart[{{5, 37, 56}, {22, 49, 28}, {31, 60, 10}}, 
 ChartLayout -> "Percentile", 
 ChartLegends -> {"1-Volume", "2-Area", "3-Length"}, 
 ChartLabels -> {{"Before", "During", "After"}, None}]