Undo/Redo button are not performing more than one operation at a time

Question

Hi,
I have created undo/redo button on my paint application. But it performing only last action to undo.I have just the code which store offscreen image into undo buffer image like this :
    if (OSC == null || widthOfOSC != getSize().width || heightOfOSC != getSize().height) {
                 // Create the OSC, or make a new one if canvas size has changed.
             OSC = null;  // (If OSC & undoBuffer already exist, this frees up the memory.)
             undoBuffer = null;
             OSC = createImage(getSize().width, getSize().height);
             widthOfOSC = getSize().width;
             heightOfOSC = getSize().height;
             OSG = OSC.getGraphics();  // Graphics context for drawing to OSC.
             OSG.setColor(getBackground());              
             OSG.dispose();
             undoBuffer = createImage(widthOfOSC, heightOfOSC);
              OSG = undoBuffer.getGraphics();  // Graphics context for drawing to the undoBuffer.
              OSG.setColor(getBackground());            
              OSG.fillRect(0, 0,widthOfOSC, heightOfOSC);
               and the button performed it's action :
else if (command.equals("Undo")) {
             // Swap the off-screen canvas with the undoBuffer and repaint.
             Image temp = OSC;
             OSC = undoBuffer;
             undoBuffer = temp;
             repaint();I want to create undo button that performed end operation on canvas.
please help me
Thanks in advance....

Answer 1

Don't post the same question repeatedly. I've removed the thread you started 4 days after this one with the identical same question.
db