Problems overlaying contour on image in uifigure

I am trying to mimic the following code:

f1=figure;

a1=gca;

hi1 = imshow(repmat(reshape(uint8(normalize(dose(:), "range")* 256), size(xg)), [1 1 3]), R, 'Parent', a1, 'InitialMagnification', 1500)

hold on

w = 17;

[~, hc] = contour(reshape(actual_positions(:, 1), w, []), reshape(actual_positions(:, 2), w, []), reshape(points, w, []), 'Parent', a1)

which works OK and outputs the following:

in a UIFigure like this:

f2 = uifigure();

a2 = uiaxes(f2);

hi2 = imshow(repmat(reshape(uint8(normalize(dose(:), "range")* 256), size(xg)), [1 1 3]), R, 'Parent', a2, 'InitialMagnification', 1500);

which displays the image OK:

The Image seems to be a child of the figure:

>> f2.Children(1).Children

ans =

Image with properties:

CData: [53×53×3 uint8]

CDataMapping: 'direct'

Show all properties

But it fails to overlay the contours properly with this code:

hold all

[~, hc] = contour(reshape(actual_positions(:, 1), w, []), reshape(actual_positions(:, 2), w, []), reshape(points, w, []), 'Parent', a2);

hc.Parent.Color = 'none';

It seems to remove the image and replace it with the contour plot instead of overlaying it.

There is only one child and it is the contour plot:

>> f2.Children(1).Children

ans =

Contour with properties:

EdgeColor: 'flat'

LineStyle: '-'

LineWidth: 0.5000

FaceColor: 'none'

LevelList: [0.0100 0.0200 0.0300 0.0400 0.0500 0.0600 0.0700 0.0800 0.0900]

XData: [17×17 double]

YData: [17×17 double]

ZData: [17×17 double]

Show all properties

Is there any way to make the behavior the same for a figure and a uifigure?

Answer 1

[Voss]

Use

hold(a2,'all')

That is, you need to specify the axes you want to hold.

[Voss]

To explain:

hold and other functions, when no axes is specified, use the CurrentAxes (which is a (ui)figure property) of the CurrentFigure (which is a Graphics Root (a.k.a. groot) property).

A uifigure will not be the CurrentFigure by default because uifigures' HandleVisibility is 'off' by default (whereas figures' HandleVisibility is 'on' by default).

So hold et al, with no axes specified, will not apply to an axes in a uifigure by default, so you need to specify which axes to apply to.

[Jonathan]

Thanks, your solution works for me, the additional explanation was usefull in understanding the mechanisms behind it. I bet I would not have found that easily through Matlab documentation/help features. :-D

[Voss]

You're welcome!