how to prevent uimenu (MATLAB) from disappearing when checked - matlab

Question

I have added uicontextmenu to the line object. uicontextmenu includes 3 check boxes. whenever I check any of them uicontextmenu disappears. I want uicontextmenu visible for sometime so that i can check multiple boxes and see the change (same as a button group but in uicontextmenu). Is there any solution to this or some other approach?
cmenu=uicontextmenu;
set(he,'uicontextmenu',cmenu);
item1=uimenu(cmenu,'label','Data A','checked','off','callback',#func_a);
item2=uimenu(cmenu,'label','Data B','checked','off','callback',#func_b);
item3=uimenu(cmenu,'label','Data C','checked','off','callback',#func_c);
basically, he is the line object created by plot(x,y) and func_a, func_b, func_c are function to convert property 'checked' to on|off.

Answer 1

This example is greatly inspired by Benoit_11 solution, but a bit refined. I was also under the impression that the 3 different functions in your callback were doing different things so I made the 3 different menus change different properties of the line (instead of changing the same property with different values).
I made the uimenu callback in one single nested function. It decides what to do based on the parameter what2do supplied at the uimenu definition (but feel free to keep 3 separate functions). However, note that the function that toggle the check mark is the same for all uimenu (you don't need a separate function for each of them).
function hf = TestUiContext2
%// Extension of Benoit_11 solution
clear ; clc ; close all
hf = figure ; %// return the handle of the figure
hax = axes; %// Create axes and save handle
plot(rand(20,3)); %// Plot three lines
hcmenu = uicontextmenu; %// Define a context menu; it is not attached to anything
%// Define the context menu items and install their callbacks
item1 = uimenu(hcmenu, 'Label','Bold line' , 'Callback' , {#uiCallback,'bold'} );
item2 = uimenu(hcmenu, 'Label','Dotted line' , 'Callback' , {#uiCallback,'dots'} );
item3 = uimenu(hcmenu, 'Label','Markers on' , 'Callback' , {#uiCallback,'mark'} );
hlines = findall(hax,'Type','line'); %// Locate line objects
for line = 1:length(hlines) %// Attach the context menu to each line
set(hlines(line),'uicontextmenu',hcmenu)
end
function uiCallback(obj,~,what2do)
hline = gco ;
switch what2do
case 'bold'
toggle_bold_line(hline)
case 'dots'
toggle_dotted_line(hline)
case 'mark'
toggle_markers(hline)
end
%// reposition the context menu and make it visible
set(hcmenu,'Position',get(gcf,'CurrentPoint'),'Visible','on')
toggle_checkmark(obj) %// toggle the checkmark
end
function toggle_checkmark(obj)
if strcmp(get(obj,'Checked'),'on')
set(obj,'Checked','off')
else
set(obj,'Checked','on')
end
end
function toggle_bold_line(hline)
if get(hline,'LineWidth')==0.5
set(hline,'LineWidth',2)
else
set(hline,'LineWidth',0.5)
end
end
function toggle_dotted_line(hline)
if strcmpi(get(hline,'LineStyle'),':')
set(hline,'LineStyle','-')
else
set(hline,'LineStyle',':')
end
end
function toggle_markers(hline)
if strcmpi(get(hline,'Marker'),'none')
set(hline,'Marker','o')
else
set(hline,'Marker','none')
end
end
end
Now you can enjoy ticking all your menu in one go ;)

Answer 2

Here is a workaround which might do the trick for you. That's not too elegant but it seems to work.
The trick is to set the menu 'Visible' property to 'on' in every callback you have (i.e. #func_a, #funct_b and #funct_c). When I run the following example (based on the demo on the Mathworks website) the menu does not disappear when the selection is changed. Notice that I created separate functions for each callback.
Here is the code:
function TestUiContext( ~)
%// Based on example from The Mathworks
%// http://www.mathworks.com/help/matlab/ref/uicontextmenu.html
clear
clc
close all
%// Create axes and save handle
hax = axes;
%// Plot three lines
plot(rand(20,3));
%// Define a context menu.
hcmenu = uicontextmenu;
%// Define the context menu items and install their callbacks
item1 = uimenu(hcmenu,'Label','dashed','Callback',#(s,e) hcb1);
item2 = uimenu(hcmenu,'Label','dotted','Callback',#(s,e) hcb2);
item3 = uimenu(hcmenu,'Label','solid','Callback',#(s,e) hcb3);
%// Locate line objects
hlines = findall(hax,'Type','line');
%// Attach the context menu to each line
for line = 1:length(hlines)
set(hlines(line),'uicontextmenu',hcmenu)
end
%// In the callback of every item/option, set the menu property 'Visible' to 'on'.
function hcb1
set(gco,'LineStyle','--');
set(hcmenu,'Visible','on')
end
function hcb2
set(gco,'LineStyle',':');
set(hcmenu,'Visible','on')
end
function hcb3
set(gco,'LineStyle','-');
set(hcmenu,'Visible','on')
end
end
And 2 screenshots to show what it looks like:
And moving the cursor down:
So as I said, not perfect but hopefully it will do the job for you!