how to undo the last action printed on an applet using undo button
Joined: Jan 23, 2001
hi, how to undo the last action printed on an applet using undo button.... im having an applet in which i can draw some lines,draw some rectangle's etc, using some buttons. i want to introduce a new button in my applet "undo". the function of this button is ,when clicked it will undo the (erase) lact action performed. can anybody help me how to do this "undo" functionality?
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Joined: Jan 09, 2001
Hi Srinivas, The example below might help you out.
The important line is show in bold. Regards, Manfred.
Joined: Dec 03, 2000
Draw all of your shapes etc. onto a BufferedImage or an offscreen Image created using the method in the Panel class. Before you draw anything onto the image, draw a copy of the image onto another offscreen image or BufferedImage. When the user hits Undo, simply revert to the last image copy that was made. This is easily done with BufferedImage - take a look at the documentation for the API. Hope that helps.