How do I make the background of a plot legend transparent?

The default background color of a plot legend is white. I want to make it transparent.

Answer 1

[MathWorks Support Team]

The background of a plot legend can be made transparent by setting the 'color' property of the legend to 'none' . This is shown in the following code sample:

plot(rand(5)); 

lgnd = legend('one','two','three','four','five');

set(lgnd,'color','none');

[Abhishek Pandey]

Hi, you can do this by turning off the 'Box' property of legend object.

set(lgnd, 'Box', 'off');

[jessupj]

I think what SN means it is possible the to set the opacity i.e. control the alpha of the background.

E.g. this won't work:

lgnd.Color = [1 1 1 0.75];

The OP's question is answered, but this isn't a general solution.

Instead, you need to do something like:

lgnd.BoxFace.ColorType='truecoloralpha'
lgnd.BoxFace.ColorData=uint8(255*[1 1 1 0.75]')

This works even with Box='off', but you may need to set EdgeColor='none' to remove it again after setting the BoxFace properties. Boxless semi-transparent legend backgrounds are my preference.

Maybe this is documented somewhere, but I can't find it to provide a reference. Note that BoxFace doesn't seem to be a visible property of the legend in the console.

[Walter Roberson]

Thanks, @jessupj