Manage multiple callbacks - matlab

Question

I have made a user interface with many edit text boxes created in loops, now I want to store the user inputs in a variable with callback.
For example consider this code,
function p = myfun()
f = figure;
set(f,'Position',[200 350 250 150],'Color',[.4 .6 .4],'MenuBar','none',...
'Visible','off');
bc = [.4 .6 .4];
uicontrol('Style','text','Position',[50 80 80 30],...
'String','X','BackgroundColor',bc,'ForegroundColor','w');
uicontrol('Style','text','Position',[50 40 80 30],...
'String','Y','BackgroundColor',bc,'ForegroundColor','w');
uicontrol('style','edit','Position', [120 80 80 30],...
'BackgroundColor',bc,'ForegroundColor','w','Callback',{#My_Callback});
uicontrol('style','edit','Position', [120 40 80 30],...
'BackgroundColor',bc,'ForegroundColor','w','Callback',{#My_Callback});
uicontrol('Style', 'pushbutton', 'String', 'Ok',...
'Position', [100 5 60 30],'Callback', 'close');
movegui(f,'center')
set(f,'Visible','on')
function My_Callback(hObject,eventdata)
p = str2double(get(hObject,'string'));
end
end
Now My_Callback will be called twice but only the last one will be stored in p.
But I want them to be stored like p.x and p.y.
I think I should use Tag, it says:
Tag
string (GUIDE sets this property)
User-specified object label. The Tag property provides a means to identify graphics objects with a user-specified label. This is particularly useful when constructing interactive graphics programs that would otherwise need to define object handles as global variables or pass them as arguments between callback routines. You can define Tag as any string.
But I don't know how (I have about 16 editable boxes),
Thanks for any help.

Answer 1

If I understood your question correctly, you could use the UserData property of uicontrols to store the content of the edit boxes as you enter it, that way it would be very easy to recover them anywhere within your GUI or elsewhere.
Moreover, to facilitate things you can assign names to uicontrols during their creation, so when you need to get one/many of their property you can call the handles with its name instead of the hObject argument.
For example, let's say you name the box with the X data x1, then you can create and store it in the handles structure of the GUI like so:
handles.x1 = uicontrol(...)
so when you need to fetch a property, you can use
get(handles.x1,'Some Property');
So to come back to your question, you could use this syntax to set the UserData property of all the boxes inside My_Callback. Afterward you can recover them in any callback you want. Of course a simple way would be to get the String property of the edit boxes instead of their UserData, but with the latter you can store anything you want which might come handy.
In the following GUI I modified yours to change the callback for the 'OK' button for a function called DisplayData which gets the UserData from each edit box and displays it.
function p = myfun()
clear
clc
f = figure;
set(f,'Position',[200 350 250 150],'Color',[.4 .6 .4],'MenuBar','none',...
'Visible','off');
bc = [.4 .6 .4];
%//===============
uicontrol('Style','text','Position',[50 80 80 30],...
'String','X','BackgroundColor',bc,'ForegroundColor','w');
uicontrol('Style','text','Position',[50 40 80 30],...
'String','Y','BackgroundColor',bc,'ForegroundColor','w');
%//===============
handles.x1 = uicontrol('style','edit's,'Position', [120 80 80 30],...
'BackgroundColor',bc,'ForegroundColor','w','Callback',{#My_Callback});
handles.y1 = uicontrol('style','edit','Position', [120 40 80 30],...
'BackgroundColor',bc,'ForegroundColor','w','Callback',{#My_Callback});
%//===============
uicontrol('Style', 'pushbutton', 'String', 'Ok',...
'Position', [100 5 60 30],'Callback', #(s,e) DisplayData);
movegui(f,'center')
set(f,'Visible','on')
guidata(f,handles); %// Updata guidata
function My_Callback(hObject,eventdata)
p = str2double(get(hObject,'string'));
%// Assign the content of the box to its "UserData" property
set(hObject,'UserData',p)
guidata(f,handles)
end
function DisplayData(~,~)
%// You could do it for all the boxes in your GUI.
x1Data = get(handles.x1,'UserData');
y1Data = get(handles.y1,'UserData');
fprintf('The number in box 1 is %0.2f and the number in box 2 is %0.2f\n',x1Data,y1Data);
guidata(f,handles)
end
end
Sample output:
And after pressing the "OK" button, this string is displayed in the Command Window:
The number in box 1 is 2.00 and the number in box 2 is 4.00
Hope that helps!

Answer 2

As you mentioned in comments, you want to read your values from editbox after the "Ok" button pressed. In order to do this, you should assign your callback function to the "ok" button, not edit boxes:
uicontrol('Style', 'pushbutton', 'String', 'Ok',...
'Position', [100 5 60 30],'Callback', {#My_Callback});
In your Callback function you should read values from all your edit boxes.
I suggest you to use handles when you defined your edit boxes (and better to use it for all the objects):
e1=uicontrol('style','edit','Position', [120 80 80 30],...
'BackgroundColor',bc,'ForegroundColor','w');
e2=uicontrol('style','edit','Position', [120 40 80 30],...
'BackgroundColor',bc,'ForegroundColor','w');
Now, in order to read values, you just use handles of the corresponding edit box.
function My_Callback(hObject,eventdata)
p1 = str2double(get(e1,'string'));
p2 = str2double(get(e2,'string'));
end
Note: this handles (e1,e2) will have cyan color in your code, that means that they are "global" variables, i.e. are used in main code and callback function.
If you don't want to use global handles, you can pass them into callback function. So your callback function will have more arguments.
uicontrol('Style', 'pushbutton', 'String', 'Ok',...
'Position', [100 5 60 30],'Callback', {#My_Callback(e1,e2)});
function My_Callback(hObject,eventdata,e1,e2)
p1 = str2double(get(e1,'string'));
p2 = str2double(get(e2,'string'));
end