Updating of uicontrol edit

Hello everyone, I am trying to build a GUI programatically in Matlab for the first time and I've run into a problem.

I have a uicontrol with the edit style. I want to take the value from this control and send it to a callback of another uicontrol (which is a pushbutton). To do this, when creating the pushbutton, I've used the following line of code:

    'UserData',struct('neededValue',editboxString.String),...

After running my program, I've noticed that this value is updated only once, when the program is run for the first time, and when I push the button the value that I receive in its callback is the default one, even if I updated the value.

Is there any way to update the value from the edit control while still using the UserData struct? I know that I can also use different methods, such as a Tag for the edit control, but if possible I would rather keep the whole program with the same style.

Thank you

Answer 1

[Robert U]

Copied from

How do I use the Edit Text box in a GUI to define variables and structure fields in another function?

My Answer

Hi Yonatan Maor,

here a solution I gave for a different question which passes handles to (possibly external) callback functions ( Can I modify inputs for pushbutton callback, answer by Jan shows another solution possibility):

Example 1

 function mytest
    GUI.a = 1;

    GUI.fh = figure;
    GUI.h1 = uicontrol('style','Edit',...
                       'string','1',...
                       'Units','normalized',...
                       'Position',[0.1 0.8 0.8 0.2],...
                       'backgroundcolor','w',...
                       'Tag','EditField');

    GUI.h2 = uicontrol('style','Edit',...
                       'string','XX',...
                       'Units','normalized',...
                       'Position',[0.1 0.1 0.8 0.2],...
                       'backgroundcolor','c',...
                       'Tag','EditField2',...
                       'Enable','off');

    GUI.h3 = uicontrol('Style','PushButton',...
                       'String','Disp a2',...
                       'Units','normalized',...
                       'Position',[0.1 0.4 0.8 0.15],...
                       'callback',{@func_compute,GUI.h1,GUI.h2},...
                       'backgroundcolor',...
                       'r','FontSize',12);

 end

 function func_compute(~,~,InHandle,OutHandle)

   a = str2double(InHandle.String);
   b = a * a;

   OutHandle.String = num2str(b);
 end

The input of first Edit-Field is used to calculate the square of itself and is displayed in a result field.

Another possibility is to use "global" variables in the context of GUI (nested) functions:

Example 2

 function mytest2

    GUI = struct;
    GUI.a = 1;

    GUI.fh = figure;
    GUI.h1 = uicontrol('style','Edit',...
                       'string','1',...
                       'Units','normalized',...
                       'Position',[0.1 0.8 0.8 0.2],...
                       'backgroundcolor','w',...
                       'Tag','EditField');

    GUI.h2 = uicontrol('style','Edit',...
                       'string','XX',...
                       'Units','normalized',...
                       'Position',[0.1 0.1 0.8 0.2],...
                       'backgroundcolor','c',...
                       'Tag','EditField2',...
                       'Enable','off');

    GUI.h3 = uicontrol('Style','PushButton',...
                       'String','Disp a2',...
                       'Units','normalized',...
                       'Position',[0.1 0.4 0.8 0.15],...
                       'callback',{@func_compute},...
                       'backgroundcolor',...
                       'r','FontSize',12);

    function func_compute(~,~)
        GUI.a;

        GUI.a = str2double(GUI.h1.String);
        b = GUI.a * GUI.a;

        GUI.h2.String = num2str(b);
    end
 end

Kind regards,

Robert