Thanks for sharing all these insights! These are really helpful.

I am currently trying to implement a focus-follows-mouse mechanism in matlab, since versions from (at least) 2015a onwards no longer support this behaviour. I have sommething that sometimes works, but not always, and I am at a loss here. I am hoping you have some ideas. I have tried the following:

function focus()
    mde = com.mathworks.mde.desk.MLDesktop.getInstance;
    cw = mde.getClient('Command Window');
    xCmdWndView = cw.getComponent(0).getViewport.getComponent(0);
    h_cw = handle(xCmdWndView,'CallbackProperties');

    function callMe(varargin)
        desktop = com.mathworks.mde.desk.MLDesktop.getInstance;
        desktop.getMainFrame.setFocusable(true);       % This one doesn't always work
        desktop.getMainFrame.requestFocusInWindow();   % This one doesn't always work
    end

    set(h_cw, 'MouseEnteredCallback', @callMe);
end

This often works, but when I, e.g., click the windows desktop first (at an empty space), only the icon in my taskbar becomes blue, but the matlab desktop does not focus. When I come from a different window, it seems to work most of the times.

I hope you can help me with this,

Temu

For an editable combobox, you need to set the focusing customizations on the internal textfield sub-component rather than on the parent JComboBox. i.e., instead of:

h3.putClientProperty('TabCycleParticipant', true);
h3.setFocusable(true)

do this:

jEditor = h3.getEditor.getEditorComponent;  % or: h3.getComponent(2)
jEditor.putClientProperty('TabCycleParticipant', true);
jEditor.setFocusable(true)

% Open figure window
hFig = figure;
% Create two stadard text boxes
h1 = uicontrol(hFig,'style','edit','position',  [10 150 150 20],'String','One');
h2 = uicontrol(hFig,'style','edit','position',  [10 120 150 20],'String','Two');
% Create an editable combo box
model = javax.swing.DefaultComboBoxModel({'a','b','c'});
h3 = javacomponent({'javax.swing.JComboBox',model}, [10 90 150 20],hFig);
% Get it to tab here
h3.setFocusable(true)
h3.putClientProperty('TabCycleParticipant', true);
% Turn it into an editable box
h3.setEditable(true);
% Add two more standard text boxes
h4 = uicontrol(hFig,'style','edit','position',  [10 60 150 20],'String','Four');
h5 = uicontrol(hFig,'style','edit','position',  [10 30 150 20],'String','Five');

It is only with the h3.setEditable(true) that the tab order is disturbed.
Anyone have any thoughts?

Thanks Dirk, I was pulling my hair out trying to figure out why setFocusable wasn’t doing it. FYI, I can confirm that this works in 14b, 15a and 15b.

@Dirk – thanks. I assume this originated from Matlab’s change of its internal Java version, from 6 to 7.

h3.setFocusable(true);
h3.putClientProperty('TabCycleParticipant', true); % only components with this property will be accepted in the focus cycle

function ths = UIedit(oParent,oSkin,sDefault)
    ths.hCtrl = uicontrol('Style','edit',...
                          'Parent',handle(oParent),...
                          'String',ths.sDefault,...
                          'Enable','off',...
                          'ButtonDownFcn',@(hCtrl,oEventData)buttonDown(ths),...
                          'Callback',@(hCtrl,oEventData)callback(ths,oEventData),...
                          'KeyPressFcn',@(hCtrl,oEventData)keyPress(ths,oEventData),...
                          'KeyReleaseFcn',@(hCtrl,oEventData)keyRelease(ths,oEventData));
    ths.jCtrl = findjobj(ths.hCtrl);
    set(ths.jCtrl,'FocusLostCallback',@(src,evnt)focusLost(ths,src,evnt));
end % class constructor

If the edit box loses focus, the focusLost method is triggered and stuff happens. And it works just fine. Except…
I also have a listbox that is a regular Matlab uicontrol:

function ths = UIlistbox(oParent,oSkin)
    ths.hCtrl = uicontrol('Style','listbox',...
                          'Parent',handle(oParent),...
                          'Max',2,...
                          'Visible','off',...
                          'Callback',@(hCtrl,oEventData)callback(ths,oEventData));
end % class constructor

The listbox is initially hidden because it serves as an auto-completion list for the edit box. You know the concept – you start typing in the edit box and the auto-completion listbox appears with suggestions. And when I press enter, or click on a listbox item, or press escape, stuff happens and the editbox is cleared and the listbox is emptied and re-hidden.
Now, the reason for the java callback is if I click away from the editbox while typing – I don’t want the regular callback to fire and capture what I entered, I just want to clear and reset. As it happens this is not a very good solution at all, but it is illustrative of the problem.

Now, here’s the problem. There are other components that belong to the uipanel parent- 5 children in total, with the order of creation such that the listbox is item #3 in the hPanel.Children array. Visually, there is another uicontrol with position coordinates that are on top of the listbox, such that I have to restack the children, like so:

function moveToFront(ths)
    hCtrl = handle(ths);
    uistack(hCtrl,'top');
end

Before restacking the java callback triggers just fine. After restacking, the java callback no longer fires. And I have no idea why. Any idea how to fix this?

Support confirmed that in R2014b we are out of luck and it is not high up in the priority list.

This seems to have broken in R2014b. Calling setFocusable doesn’t seem to have any effect now.

For example:

figure(101)
clf

% Add a text uicontrol to label the slider.
txt = uicontrol('Style','edit', 'Position',[400 45 120 20], 'String','Vertical Exaggeration');

jButton = javax.swing.JButton('Click me!');
jbh = handle(jButton,'CallbackProperties');
set(jbh, 'ActionPerformedCallback', @(varargin) disp('CLICKED!'))
[hjButton,hContainer] = javacomponent(jButton, [10,10,80,20], gcf);

jButton.setFocusable(true);
jButton.requestFocus();

uicontrol('Style','text', 'Position',[100 245 240 60],...
    'String','Press TAB - java button should get focus...','FontSize',16);

If you run this in R2014a, then by pressing TAB and ENTER one can make the “CLICKED” message appear in the command window.

But in R2014b, pressing TAB will never give focus to the java button.

Do you have any ideas how to work around this?

Thanks,

Chris.