This script will give you the ability to put an EMA and/or SMA on the chart that changes color based upon the direction. Default at startup is EMA visible and SMA hidden. When the MA is moving up, it is green. When the MA is moving down, it is red. You can change the color to whatever you like.
//Created by Robert Nance on 072315 study(title="Moving Average Colored EMA/SMA", shorttitle="Colored EMA /SMA", overlay=true) emaplot = input (true, title="Show EMA on chart") len = input(8, minval=1, title="ema Length") src = close out = ema(src, len) up = out > out[1] down = out < out[1] mycolor = up ? green : down ? red : blue plot(out and emaplot ? out :na, title="EMA", color=mycolor, linewidth=3) smaplot = input (false, title="Show SMA on chart") len2 = input(8, minval=1, title="sma Length") src2 = close out2 = sma(src2, len2) up2 = out2 > out2[1] down2 = out2 < out2[1] mycolor2 = up2 ? green : down2 ? red : blue plot(out2 and smaplot ? out2 :na , title="SMA", color=mycolor2, linewidth=1)