Error displaying custom Data Tips

I've created a callback to displaying Data Tips on a pointcloud (pcshow) after the space bar is pressed. The flow is:

• Press on the space bar
• click on a point
• custom data tips appear

At first, the DataTip shows an error message, but if I click on the data tip or in general over the figure, the correct data tip appears and the error message does not show again. How can I avoid the appearence of that message? Where should I look for the problem?

Error message: unable to update data tip using custom update function.

Thank you.

[Asvin Kumar]

Please share your code on what you're currently doing so that the community can help you. It's hard to suggest solutions when we don't know what's going on in the first place.

If possible, share only the minimum relevant code. 100s of lines of code would only confuse anyone who is interested to help.

[Veronica Taurino]

Thank you for your reply. It's not (yet) a neat and efficent code, don't judge me please ahah

I create a tab panel with 3 figures (pcshow function, they are point clouds). When the user clicks the space bar on a figure, 3d rotation mode has to quit and the ''datatip'' mode starts, so that when the user clicks on a point over the point clouds, datatips are added to the figure. Then, when the user pushes the space bar again, the datatips are hidden and 3D rotation mode starts again.

Please note that to allow the callback during the 3D rotation mode, I used this undocumented Matlab code:

https://undocumentedmatlab.com/articles/enabling-user-callbacks-during-zoom-pan

function [hTabGroup] = PlotInTab(path_pc)
ptCloud = plyread(path_pc);
struct_data={'1','2','3'; ptCloud.vertex.one, ptCloud.vertex.two , ptCloud.vertex.three};

hTabGroup = uitabgroup; 
drawnow;

% Plot
for iFig = 1:3         
      tab = uitab(hTabGroup, 'title',struct_data{1,iFig});
      tab_all{iFig}=tab;
      a = axes('parent', tab_all{iFig});        
      pc(iFig)=pcshow([ptCloud.vertex.x ptCloud.vertex.y ptCloud.vertex.z], struct_data{2,iFig},'Parent',axes_all{iFig});                                        
      %[...Stuff - custom colorbar, colormap, colorbar tick...]            
      %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
      % https://undocumentedmatlab.com/articles/enabling-user-callbacks-during-zoom-pan
       hFig=pc(iFig).Parent.Parent.Parent;
       hManager = uigetmodemanager(hFig);
       try
           set(hManager.WindowListenerHandles, 'Enable', 'off');  % HG1
       catch
           [hManager.WindowListenerHandles.Enabled] = deal(false);  % HG2
       end
       set(hFig, 'WindowKeyPressFcn', []);
       set(hFig, 'KeyPressFcn', @isspace); % callback 2
       %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
       set(gcf, 'MenuBar', 'none');
       set(gcf, 'ToolBar', 'none');
       axis 'equal'
       axis 'tight'
       axis  'off'    
end      

% Global variables - callback 
setGlobalx(0) 
end

%% 1. Callback: Display DataTips %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function txt = displayCoordinates(hObject,info)
    hObject.Parent.Children.DataTipTemplate.DataTipRows(1).Label='X';
    hObject.Parent.Children.DataTipTemplate.DataTipRows(2).Label='Y';
    hObject.Parent.Children.DataTipTemplate.DataTipRows(3).Label='Height';
    % Add Value row to the datatips:
    hObject.Parent.Children.DataTipTemplate.DataTipRows(4).Label='Value';
    hObject.Parent.Children.DataTipTemplate.DataTipRows(4).Value='CData';
 end

%% 2. Callback: When space bar is pushed, starts "datatips" mode %%%%%%%%%%%%%%%%%%
function isspace(hObject,~)          
    % check state space bar button: 0 - show datatips, 1: hide datatips
    check_state=getGlobalx(1);
    setGlobalx(1,check_state+1);
                  
    if check_state==0   %  If global variable is 0, shows DataTips

        dcm = datacursormode;        
        dcm.Enable = 'on'; 
        dcm.UpdateFcn = @displayCoordinates; % per le coordinate  
        if isempty(hObject.Children(end).SelectedTab.Children(end).Children.Children)
            waitforbuttonpress(); %to avoid errors ?
        end
        hObject.Children(end).SelectedTab.Children(end).Children.Children.Visible='on' ;
        pause(0.01); drawnow; 

    else % If global variable is 1, hide DataTips        
        dcm = datacursormode;
        dcm.Enable = 'off';              
        hObject.Children(end).SelectedTab.Children(end).Children.Children.Visible='off' ;
        rotate3d on
        pause(0.01); drawnow;        
        setGlobalx(1,0);
    end     
    %%%
    hManager = uigetmodemanager(hFig);
    try
        set(hManager.WindowListenerHandles, 'Enable', 'off');  % HG1
    catch
        [hManager.WindowListenerHandles.Enabled] = deal(false);  % HG2
    end
    set(hFig, 'WindowKeyPressFcn', []);
    set(hFig, 'KeyPressFcn', @isspace);
end

[Asvin Kumar]

Hey, this is going to be hard to debug. I'm out of bandwidth at the moment and won't be able to look into it immediately.

A few suggestions to make it easier for others in the community:

1. Provide a way to reproduce the behaviour. Maybe provide some code which people can quickly execute and start tinkering with.
2. Or, if possible, come up with a short demo of your problem by just using scatter plot like in this example.
3. Provide more details on waitforbuttonpress() because it seems like you've added that to work around your problem. What does it do? Does it work?