@Ozgu – yes you can but only if you create a dedicated Java cellrenderer class for this (i.e., not in pure Matlab)

Thank you for your answer Yair,

Ok. Can I add a mouse hover event for each item for Jcombobox

Thanks again

Ozgu

@Ozgu – combobox popups are not the same as listboxes, although they share some common aspects. For example, combo-box items do not have tooltips by default – only the main edit-box component of the combo-box has a tooltip. It is indeed possible to use Java to display a tooltip for each combo-box item (using a dedicated renderer, example 1, example 2), but this is not easy to achieve in Matlab, and is beyond the scope of this post.

I applied dynamic tooltip example on jcombobox, but there is no
“locationToIndex” property for jcombobox.

How can I overcome this problem?

Thanks

Ozgu

@Claudio – I don’t know why you posted this question here – it seems to relate to popup/dropdown menus and not listboxes. In any case, such menu items cannot be modified using the setBackground method, you need to either use a custom Java cell-renderer object, or modify the menu string to include HTML background, for example:

menuCheck.setText(sprintf('Check recording',bgcolor))

how can I change background color for jmenu described in the previous example?
I try

menuCheck = javax.swing.JMenuItem('Check recording');
bgcolor = get(gcf,'Color');   % background color = white 
menuCheck.setBackground(java.awt.Color(bgcolor(1),bgcolor(2),bgcolor(3)));
menuCheck.repaint

But the classic gray background color does not change…

Thanks Yair,

I looked at your book and I found some part of the modification I should implement on p. 414:

hFig = figure;

% Prepare the list of JLabel objects
iconsFolder = fullfile(matlabroot,'toolbox/matlab/icons'); 
imgs = dir(fullfile(iconsFolder,'*.gif'));
for idx=1 : length(imgs)
    iconFilename=fullfile(iconsFolder, imgs(idx).name); 
    iconTooltip=['Item-specific tooltip: ' imgs(idx).name]; 
    jLabels{idx} = javax.swing.JLabel; 
    jLabels{idx}.setIcon(javax.swing.ImageIcon(iconFilename)); 
    jLabels{idx}.setText(imgs(idx).name); 
    jLabels{idx}.setToolTipText(iconTooltip);
end

% Set the JLabel objects in the model 
set(jPopup,'String',{imgs.name}); % ensure consistent HG size 
model=javax.swing.DefaultComboBoxModel; %not DefaultListModel 
for idx=1:length(imgs)
        model.addElement(jLabels{idx});
end 
jPopup.setModel(model);

% Set the display Renderer
% Note: LabelLisitBoxRenderer was presented in section 6.6 above 
jPopup.setRenderer(LabelListBoxRenderer); %not setCellRenderer() 
jPopup.setFixedCellHeight(16); % give the icons some space... 
jPopup.setMaximumRowCount(8); % override the default 20

I added the hFig = figure; at the beginning but there is still some part of the code missing especially the part that define jPopup and where you place it. Can you give me some hint ?

Thanks in advance

Jonathan

@Jonathan – popups do not use a viewport in the same manner as a listbox. You can have more control over the appearance and behavior if you use JIDE comboboxes directly, as briefly explained here and in more detail in my Matlab-Java book.

First thank you for your amazing website, it has been really useful for me !

I would like to have different tooltips for the different object of my popupmenu.

I tried to use the same idea that you are using for the uicontrol ‘Listbox’ but for a uicontrol ‘Popupmenu’. I just want to have the dynamic tooltips.
I tried to simply replace ‘Listbox’ by ‘Popupmenu’ in the code but it does’t work. I got the error :

No appropriate method, property, or field 'getViewport' for class 'javahandle_withcallbacks.com.mathworks.hg.peer.ComboboxPeer$MLComboBox'.

I used uiinspect to check and I saw that there is no getViewport in the jScrollPane when I use the uicontrol ‘Popupmenu’

I am not familiar with java so I have trouble to figure out what I should modify to have the code working with ‘Popupmenu’

Thanks in advance

Jonathan

@Ilya – perhaps you can get the clicked location (X,Y) and compare this to the knob’s position, ignoring locations outside it.