controlling background color of selected uicontrol popup?

I can create a uicontrol('Style','popup') with a 'backgroundcolor'. This works and the color is the one I chose. However, as soon as I select any value, the background color goes to a grayish, with the text in the foreground color I have set. The selected pop-up entry does not use the background color.

Is there a way to control the background color of a selected pop-up entry?

(I am trying to color-code my uicontrols according to the major class of functionality they have within the terms of my program. Although I could in theory do so just by adjusting their text foreground colors, the area of the text compared to the area of the control is relatively small and the color coding of the text is not nearly as distinguishable as color coding the background.)

[Walter Roberson]

Dang. Jan's technique worked for popups, but not for a list box. I had to force it to unrender (by setting max to 1 on a multivalued list) and rerender. That emits a warning each time, so I don't want to handle things that way. Oh yes, changing the box size massively wasn't enough of a re-rendering!

[Jan]

Does REFRESH(FigHandle) help?

[Walter Roberson]

Alas, refresh() doesn't do a thing. It doesn't even cause the figure to flash momentarily if I'm stepping in debug mode.

Answer 1

[Jan]

The selected pop-up gets the different color as long as the UICONTROL has the focus. Although Matlab's documentation claims that "figure(gcf)" gives the focus to the figure, this does not work from at least Matlab 5.3 to 2009a. Therefore I usually insert a call to a function named "FocusToFig" in the UICONTROL's callback function:

function FocusToFig(ObjH, EventData)  %#ok<INUSD>
% Move focus to figure
% FocusToFig(ObjH, [DummyEventData])
% INPUT:
%   ObjH: Handle of a graphics object. It is tried to move the focus to the
%         parent figure and making it the CurrentFigure of the root object.
%   DummyEventData: The 2nd input is optional and ignored.
%
% Tested: Matlab 6.5, 7.7, 7.8, WinXP
% Author: Jan Simon, Heidelberg, (C) 2009-2011

if any(ishandle(ObjH))   % Catch no handle and empty ObjH
   FigH = ancestor(ObjH, 'figure');
   if strcmpi(get(ObjH, 'Type'), 'uicontrol')
      set(ObjH, 'enable', 'off');
      drawnow;
      set(ObjH, 'enable', 'on');
   end

     % Methods according to the documentation (does not move the focus for
     % keyboard events under Matlab 5.3, 6.5, 2008b, 2009a):
     figure(FigH);
     set(0, 'CurrentFigure', FigH);
  end

return;

This moves the keyboard focus also to the figure, such that the KeyPressFcn is called again.

[Walter Roberson]

The grayish color is retained even when focus moves elsewhere. A uicontrol popup that has focus has a single-pixel rectangle of color drawn around the outside of it (it looks orange-y at least with the controls I tested on.)

[Jan]

The main task of my function for your purpose is not to move the focus, but to disable the UICONTROL temporarily, what forces a redraw.

Because the moving of the focus does not work correctly under Windows for 10 years, I expect there could be corresponding problems for a Ubuntu64 server displayed to a Linux32 client...

Answer 2

[Matt Fig]

Things seem to work here as you wish, unless I misunderstand you.

uicontrol('Style','popup','backgroundcol',[.9 .7 .3],'string',{'P';'Y';'F'})

This creates a popupmenu with an orange-ish bgc. After I select any of the three strings, the bgc is the same.

[Walter Roberson]

2008b, Linux-64 (Ubuntu) server displayed to Linux-32 (Ubuntu), after I select any of the strings, the background turns to gray . The control is outlined in orange as long as the control has focus.

If set() the background of the control when it has something selected by the user, nothing changes. If I set() the Value of the control, the appropriate entry comes up but the color is still wrong.

But! If I set the Value of the control so that it does not render (generating a warning) and then set the Value back again, then when the control re-appears it will have the appropriate entry and the appropriate background color. And if I then set the Value to something else without clicking on it, the new appropriate entry is displayed, still with the right background.

Thus this has something to do with the clicking rather than the change in Value.

Perhaps it is an (ahem) "undocumented feature" for this configuration.

[Jan]

And this is exactly what my suggested method does: Disable the uicontrol temporarily, what forces a redraw. The moving of the focus is just a side-effect. Did you try my function?

[Walter Roberson]

Jan, you are right, disable / drawnow / enable does get the color back to what it should be.

[Walter Roberson]

s/write/right/

(We need a commented editor!)

[Walter Roberson]

Aggh. We need a *comment* editor!

[Jan]

Fine. Is your problem solved then?

Answer 3

[Daniele Scaranari]

figure(gcf) works correctly in Matlab R2017a, Windows10.