Pine：如何根据条件设置背景颜色

Question

I'm trying to have the entire background colored on a condition (eg green) if the last close is above the close 50 bars back and red if it's below.
I've tried different approaches and I can change the color, but it doesn't end up coloring the entire background, but only certain areas.

My script:

bgcolor(close[50] >= open[1] ? color.red : color.green, transp=70)

split colors in background

In this case the entire background should be red, since the last close is below the close 50 bars back (indicated by the yellow label).
Any ideas on what I need to change?

Answer 1

This will color the background on your condition. It uses a very wide line to do it, and because of that the indicator is occupying all the background, so some chart functions like the measuring tool cannot be used with Shift-Click, but it will work if you select its tool explicitly.

You can play with the position and width of the background if you don't want it to cover the whole chart.

The background is very light. If you want to change its brightness, you'll need to play with the transparency in the two color.new() calls, as it cannot be controlled from an input:

//@version=4
study("", "", true)

offsetCalc  = input(50,     "Close lookback", minval = 2)
offstBg     = input(100,    "Background: Horizontal Offset to its Center", minval = 0, step = 5)
lineWidth   = input(10000,  "Background: Width", minval = 0, step = 100)

condUp      = barstate.islast and close[1] > close[offsetCalc]
condDn      = barstate.islast and close[1] < close[offsetCalc]
c_lineColor = condUp ? color.new(color.green, 97) : condDn ? color.new(color.maroon, 97) : na

if barstate.islast
    var line bg = na
    line.delete(bg)
    bg := line.new(bar_index[offstBg], low - tr, bar_index[offstBg], high + tr, color = c_lineColor, extend = extend.both, width = lineWidth)