Wait until user press return key to continue script

I have a script plotting a figure with some vertical lines. I then want the user to select some of the lines and output a table with each line's index. I need the script to pause until the user has selected all the lines they want (and press 'enter' to indicate they are finished, for example), and then resume the script to save the selected indices in a table.

Here is my script:

clear, clc, close all
figure
x = rand(1,41);
y = 1:41;
H(1)= plot(x,y,'r.');
H(2)= line([x(21) x(21)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(3)= line([x(3) x(3)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(4)= line([x(15) x(15)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');

set(H, 'ButtonDownFcn', {@LineSelected, H})

% WANT TO PAUSE HERE: WAIT FOR USER TO PRESS RETURN KEY (FOR EXAMPLE)
% THEN RESUME WITH BUILDING THE FOLLOWING TABLE
IndInWorkSpace = reshape(IndInWorkSpace, 2, [])';
ipt_sec = array2table(IndInWorkSpace,'VariableNames',{'start','end'});
ipt_sec.duration = ipt_sec.end - ipt_sec.start;


function LineSelected(ObjectH,EventData, H)
    set(ObjectH, 'LineWidth', 4);
    set(H(H ~= ObjectH), 'LineWidth', 2);
    % Get x and y data of the highlighted lines
    ind = ObjectH.XData(1);
    if evalin('base','exist(''IndInWorkSpace'',''var'')')
        indArray = evalin('base','IndInWorkSpace');
        indArray(end+1) = ind;
    else 
        indArray = ind;
    end 
    assignin('base', 'IndInWorkSpace', indArray);
end

Any help appreciated, many thanks!

Answer 1

[Benjamin Kraus]

Another option is to use waitfor along with a WindowKeyPressFcn.

x = rand(1,41);
y = 1:41;
H(1)= plot(x,y,'r.');
H(2)= line([x(21) x(21)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(3)= line([x(3) x(3)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(4)= line([x(15) x(15)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
set(H, 'ButtonDownFcn', {@LineSelected, H})
set(gcf,'WindowKeyPressFcn', @(~,~) set(gcf,'UserData', true));
waitfor(gcf,'UserData')

IndInWorkSpace = reshape(IndInWorkSpace, 2, [])';
ipt_sec = array2table(IndInWorkSpace,'VariableNames',{'start','end'});
ipt_sec.duration = ipt_sec.end - ipt_sec.start;

function LineSelected(ObjectH,EventData, H)
    set(ObjectH, 'LineWidth', 4);
    set(H(H ~= ObjectH), 'LineWidth', 2);
    % Get x and y data of the highlighted lines
    ind = ObjectH.XData(1);
    if evalin('base','exist(''IndInWorkSpace'',''var'')')
        indArray = evalin('base','IndInWorkSpace');
        indArray(end+1) = ind;
    else 
        indArray = ind;
    end 
    assignin('base', 'IndInWorkSpace', indArray);
end

[Butterflyfish]

That works perfectly, thank you so much for your help!

Answer 2

[Benjamin Kraus]

One option is to add a WindowKeyPressFcn that runs the rest of your code. Something like this:

x = rand(1,41);
y = 1:41;
H(1)= plot(x,y,'r.');
H(2)= line([x(21) x(21)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(3)= line([x(3) x(3)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
H(4)= line([x(15) x(15)],[0 max(y)], 'LineWidth', 2, 'Color', 'k');
set(H, 'ButtonDownFcn', {@LineSelected, H})
IndInWorkSpace = [];
set(gcf,'WindowKeyPressFcn', @keyPress)

function LineSelected(ObjectH,EventData, H)
    set(ObjectH, 'LineWidth', 4);
    set(H(H ~= ObjectH), 'LineWidth', 2);
    % Get x and y data of the highlighted lines
    ind = ObjectH.XData(1);
    if evalin('base','exist(''IndInWorkSpace'',''var'')')
        indArray = evalin('base','IndInWorkSpace');
        indArray(end+1) = ind;
    else 
        indArray = ind;
    end 
    assignin('base', 'IndInWorkSpace', indArray);
end

function keyPress(~,EventData)

IndInWorkSpace = evalin('base','IndInWorkSpace');
IndInWorkSpace = reshape(IndInWorkSpace, 2, [])';
ipt_sec = array2table(IndInWorkSpace,'VariableNames',{'start','end'});
ipt_sec.duration = ipt_sec.end - ipt_sec.start;
assignin('base', 'ipt_sec', ipt_sec);

end