How can I get the data selected by the user with the datacursor in a Gui?

I have been tryng to create a gui where a user selects a point in a graph. I want to get the user selection to run another function later. I tried to create a function callback in the points in the graph but did not work. How do I create a callback to the graph points?

Thanks.

Answer 1

[Oleg Komarov]

An example with a line object, save as file and run exampleGUI:

function exampleGUI
lnH(1) = line(1:12,-1:10, 'lines'  ,'none',  'marker' ,'.',  'markers',15,...
                          'markere','k'   ,  'buttond',@ln_buttond);
% Additional enlarged marker to highlight selected point
lnH(2) = line(1,-1,  'lines'  ,'none',  'marker' ,'o',...
                      'markere','r'  ,  'markers',8);

      function ln_buttond(varargin)
          % Retrieve Xdata and Ydata 
          XY = get(lnH(1),{'Xdata','Ydata'});
          % Get mouse position inside axes
          cpaxes = get(gca,'currentpoint');
          % Index the click
          idx    = abs(cpaxes(1) - XY{1}) < 0.25;
          % Highligth with bigger marker
          set(lnH(2),'Ydata',XY{2}(idx),'Xdata',XY{1}(idx));
      end
  end

Oleg

Answer 2

[Aurelien Queffurust]

Have you tried the ButtonDownFcn callback?

[Fernando]

I did but nothing happens with the callback. When I click the points it doesn't do anything, as if the callback did not exist.

[Paulo Silva]

it isn't that simple

[Fernando]

I know, I already wasted 2 days of my life.

[Oleg Komarov]

Then try Paulo's or my solution below.

[Paulo Silva]

My solution doesn't use the datacursor, it just gets the current point when the user clicks on the figure, that was because the datacursor function implements it's own callbacks, I would suggest some alterations to the datacursormode function (make a custom one) but it's not easy.

Maybe adding the detection of the return key or space key in the code

% Parse key press

movedir = [];

switch keypressed

case 'leftarrow'

movedir = 'left';

case 'rightarrow'

movedir = 'right';

case 'uparrow'

movedir = 'up';

case 'downarrow'

movedir = 'down';

case 'alt'

consumekey = true;

end

Make it do something else when those keys are detected but it might not be easy.

I recall that something similar was already discussed and Jiro proposed a solution here on answers, I think I have the code somewhere in my laptop :s

[Oleg Komarov]

The solution I proposed gets just the point clicked.

[Fernando]

Thank you Paulo, Oleg and Aurelien. Paulo and Oleg answers made my day.

Muito Obrigado!

Answer 3

[Paulo Silva]

function testbdown
fig=figure;
ax=axes;
set(ax,'ButtonDownFcn',@detbut);
    function detbut(a,b)
    cp=get(a,'CurrentPoint');
    x=cp(1,1)
    y=cp(1,2)
    %comment the next line if you want to keep getting x,y for more points 
    set(ax,'ButtonDownFcn','');  
    %hold on %in case you want to keep several points marked on the axes
    %plot(x,y,'x') %in case you want to mark the points
    end
end