Why does findobj not work with annotation tags?

When I create an annotation with a Tag and use findobj the result is empty.

an = annotation('textbox',[0 0 1 1],'string','Hallo','Tag','annotation');
findobj('Tag','annotation')

[Walter Roberson]

Is it possible that the handle is hidden ?

Answer 1

[per isakson]

findall returns the hg-handle. However, I find it strange that findobj fails, since HandleVisibility is on (by default). Matlab seems to behave this way and documentation is hard to read.

    >> an = annotation('textbox',[0 0 1 1],'string','Hello','Tag','annotation');
    >> h1 = findobj('Tag','annotation')
    h1 =
       Empty matrix: 0-by-1
    >> h2 = findall(0,'Tag','annotation')
    h2 =
      178.0016
    >> get( h2, 'HandleVis' )
    ans =
    on
    >>

With R2012a,64bit,Win7

.

@Walter

Yes, an and h2 seems to be the same

    ....
    >> [an,h2]
    ans =
      178.0024  178.0024
    >> get( [an,h2], 'type' )
    ans = 
        'hggroup'
        'hggroup'
    >> get( [an,h2], 'tag' )
    ans = 
        'annotation'
        'annotation'
     >>

However, you spotted the cause

    >> axh = get( h2, 'parent' )
    axh =
      173.0024
    >> get( axh, 'HandleVis' )
    ans =
    off

annotation returns the handle of a hggroup, which is the child of an axes the HandleVisibility of which is off.

[Walter Roberson]

but is h2 the same as "an" ?

If the object that got tagged got created as a child of something with an invisible handle, what you describe would be the result.

[yosey]

Thank you both.