MatLab GUI plotting a line that updates with button press - matlab

Question

So I'm working on MatLab GUI assignment right now.
It's basically an estimation game. In every trial the user guesses the correlation displayed on the left axes. When they click submit my code calculates the absolute value of the difference between their estimation and the actual correlation.
So far so good.
On the right axes I want to plot a line that updates every time they click "submit". The x-coordinate would be the trial # and the y-coordinate would be the absolute difference previously mentioned.
I can plot this information successfully using points instead of a line by using "scatter" or "plot", but when I try to make it a line, nothing appears, although the axis does seem to update...
Both of the following codes work if the marker is '.' or 'o' or 's' or 'x' ... literally any marker.. but I can't get it to connect the dots... I've messed around with trying to use animated line and drawnow but that didn't work out for me either..
plot(handles.trial, handles.diff(handles.trial),'-.'); hold on; %plot trialwise absolute differences
or
scatter(handles.trial, handles.diff(handles.trial),'-.'); hold on; %plot trialwise absolute differences
**Problem solved!
see the solution below

Answer 1

Solution:
Store all of the relevant data in a matrix handles.DATA. For this to work there needed to be something in there before the first trial so during initialization I set handles.DATA = [0 0] and then with the button-press (submit) that ends a trial, the data from that trial got concatenated into the data matrix: handles.DATA = vertcat(handles.DATA, [x y]). Below this I could do the plot that I wanted to: plot(handles.DATA(:,1), handles.DATA(:,2),'Color','r'
*note: don't hold on because then you will have lines stacking on each other.
**also if you don't specify line color, the line will become a different color every time you click "submit" because this is generating a new line every time based off the updated information.