how to draw line in different colors ?

[surabhi-1694]

i am trying to draw line in different colors
though i am able to change color of line from white to Different color
BUT the problem is the selected color apply to all the Lines
What i am trying to achieve is if i select color red line should be in red color then if yellow color is selected the next line should be in yellow color and the previous drawing(line) should remain in red
if any one can help to Achieve this
Thanks.