MATLAB: How to create undo and redo buttons in GUI that can be pressed multiple times

guiguideMATLABmatlab gui

Hello everyone! I have a working GUI where I have a undo and redo buttons. I have saved the current and previous states in two variables and implemented them in the respective callbacks. But I can undo and redo for only once. I guess the data is being overwritten everytime. Is there a way around it? Or a easier solution?

Thanks in advance!

Best Answer

John - without seeing your code, we can't determine why it is allowing you to undo and redo only once. You mention that you have saved the current and previous states in two variables. Are these scalar variables? If I were to implement redo and undo functionality, then I might use an array of some kind that would push the states to the front of the array so that when I call undo, the front would be popped up and the variables (or whatever) updated with the new front of the array. The popped off data would be pushed to the front of the redo array so that if I chose to call redo, then it's front would be popped off. There is lots more that you would have to consider - when should the redo array be emptied, when should the undo array be emptied, etc.

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