java - How to continue draw something on JPanel after clicked the button without repaint? -


i have define jpanel named drawpanel, , button named jbutton1 actionlistener. want continue draw on drawpanel after clicked jbutton1. , not want clear drawpanel first , draw more things, want continue draw on drawpanel , show in jframe.

check out custom painting approaches 2 common ways this:

  1. keep list of objects want paint , iterated through list every time.
  2. paint bufferedimage , paint bufferedimage.

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