Why is line visible while its parent axes is unvisible?

Say a script as following,

fig = figure;
ax = axes(fig, 'Visible', 'on');
plot(ax, 1:8, cos(pi*(1:8)),'r-x');
set(ax, 'Visible', 'off');

Why is the line still visible?

Answer 1

[Steven Lord]

Because the line has its own Visible property and that property's value is 'on'.

fig = figure;
ax = axes(fig, 'Visible', 'on');
h = plot(ax, 1:8, cos(pi*(1:8)),'r-x');
set(ax, 'Visible', 'off');

lineVisiblePropertyValue = h.Visible

lineVisiblePropertyValue = 
  OnOffSwitchState enumeration

    on

[Rik]

I would have expected the line object to follow the parent axes property (just like would happen if you set(fig, 'Visible', 'off');). I understand why it doesn't work like that, but that is what I would expected.

[Steven Lord]

Just because two or more Handle Graphics objects have properties with the same name doesn't mean those properties are synchronized. In the code below, changing the figure's Color property does not change the Color properties of the axes or the line inside the figure.

h = plot(1:10);
ax = ancestor(h, 'axes');
f = ancestor(h, 'figure');
f.Color = 'r';

fprintf("%s", "The line has color [" + join(string(h.Color), ",") + "] " + ...
    "while the axes has color [" + join(string(ax.Color), ",") + "] " + ...
    "and the figure has color [" + join(string(f.Color), ",") + "].")

The line has color [0,0.447,0.741] while the axes has color [1,1,1] and the figure has color [1,0,0].