Update slider value while in a for loop.

4 views (last 30 days)
Sampath reddy
Sampath reddy on 6 May 2012
I am running a program in GUI.It contains a for loop. One of the parameters in the program is controlled by slider. While inside the for loop, i want to change the slider value so that the program continues to run with the new slider value. How to do this?

Answers (2)

Walter Roberson
Walter Roberson on 6 May 2012
set(SliderHandle, 'Value', NewValue)
However, this will not be enough if the program fetches the slider value and stores it and then uses the stored value instead of re-fetching the slider value.

Image Analyst
Image Analyst on 6 May 2012
If you want the user to change it interactively while the loop is running, you can get the value inside your loop.
sliderValue = get(handles.slider, 'Value');
Again, that is inside your loop.
When the user moves the slider, the slider callback gets called. In that callback, be sure and call "drawnow" or else it might be so involved in your loop that it won't have time to update your slider caption right away. I'm assuming you have a static text above your slider that gives the value, something like:
sliderValue = get(handles.slider, 'Value');
sliderCaption = sprintf('The slider value = %f', sliderValue);
set(handles.slidertext, 'String', sliderCaption);
drawnow;
  2 Comments
Sampath reddy
Sampath reddy on 7 May 2012
I'm getting an error saying Invalid or deleted object(handles.slider) for the line sliderValue = get(handles.slider, 'Value');
I'm unable to figure out the problem
Image Analyst
Image Analyst on 7 May 2012
Are you using GUIDE? What is the name of the handle to your slider? If you're using GUIDE, this is the 'tag' property.

Sign in to comment.

Categories

Find more on Interactive Control and Callbacks in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!