MATLAB Answers


how to get string for empty Edit Text in Matlab GUI ?

Asked by MatlabFan
on 6 Apr 2013


I inserted an Edit Text in a Matlab GUI, and I would like to perform some actions when nothing is in the Edit Text (Edit Text empty). I have the following:


The problem is that, when the Edit Text is empty, isempty(extractPass)= 0. I was expecting isempty(extractPass)=1 when the Edit Text is empty.

What do I need to write to know when the Edit Text is empty ?





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1 Answer

Answer by per isakson
on 6 Apr 2013
 Accepted answer

With R2012a I fail to reproduce your problem. Try

    class( extractPass )
    double( extractPass )

to find out what get returns


I made a little experiment:

    >> ohe = uicontrol( 'Style', 'edit', 'max', 3,'min',1 )
    ohe =
    >> set(ohe,'String', {'abc','dfg'})

deleted the strings in the editbox interactively and

    >> str=get(ohe,'String')
    str = 
    >> isempty( char( str ) ) 
    ans =

or better

    isempty( [str{:}] )

the char doesn't hurt if str is character, but if str not a scalar it might. Matlab is sometimes tiresome!

Thank you very much for your help Isakon. I appreciate that. It still doesn't solve the problem though.

You have a < 2x1 cell> array of strings (or something else). Try this

    whos extractPass
    for ii = 1 : numel( extractPass )
        class( extractPass{ii} )
        isempty( extractPass{ii} )

or use the variable editor to find out what is in the cells.

Do you have a squeezed scroll bar to the right end of the edit box?

If nothing helps restart Matlab!

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