Make Pushbutton Visible in GUI

I'm attempting to make a pushbutton visible in my GUI when a specific selection is picked in the popup menu. Here's my code:

hbutton0 = uicontrol('Style','pushbutton','String','Load Time','Position',...
    [150,365,90,30],'Callback',@callbackfn);
set(hbutton0,'Visible','Off')

hspopup0 = uicontrol('Style','popup','BackgroundColor','white','position',[20,350,100,40],'String',{'Modality';'PBS';'DS'});

if strcmp(get(hspopup0,'String'),'PBS')
    set(hbutton0,'Visible','On');
end

Yet the hbutton0 does not appear when 'PBS' is selected. Can you please help? Thank you.

Answer 1

[Walter Roberson]

The String property of a uicontrol('Style','popup') always holds all of the menu items, not just the currently selected item. In order to determine the currently selected item, you need to look at the numeric property Value of the uicontrol (which can be empty if nothing has been selected.) You can get() the String property and index it by the Value property if you want to know the string that was selected.

Answer 2

[Image Analyst]

% Get the index of the item they chose.
selectedIndex = get(hspopup0, 'Value');
% Get a list of everything in the popup.
allItems = get(hspopup0,'String'); % Cell array of all items in the popup
% Get the string indicating the exact one item that they chose.
selectedItem = allItems{selectedIndex};
% Now do the comparison.
if strcmp(selectedItem ,'PBS')
    set(hbutton0,'Visible','On');
end

[Image Analyst]

Or, even better if you know what index PBS is at:

% Get the index of the item they chose.
selectedIndex = get(hspopup0, 'Value');
% Now do the comparison.
if selectedIndex  = 3 % Or whatever number PBS happens to be at
    set(hbutton0,'Visible','On');
end

[Adam Glick]

I've actually tried both those methods already and neither one will make my button visible when I select 'PBS'.

[Walter Roberson]

Works for me when I test it by using your code

hbutton0 = uicontrol('Style','pushbutton','String','Load Time','Position',...
    [150,365,90,30],'Callback',@callbackfn);
set(hbutton0,'Visible','Off')

hspopup0 = uicontrol('Style','popup','BackgroundColor','white','position',[20,350,100,40],'String',{'Modality';'PBS';'DS'});

and then selecting the PBS entry and then using Image Analyst's code.

If you are looking to have it immediately switch then you would need to set up a callback on hspopup0

[Image Analyst]

Use the debugger to step through your code and find out what lines of code it's actually executing.