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

What I am trying to do seems simple but I cannot figure it out. Lets say I have variable A in a function. How do I make whatever I enter in a text box define variable A? Same thing with defining fields in a structure, how can I use the edit text box to define them?

Answer 1

[Robert U]

Hi Hector De La Torre,

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