Hey there, let's break down what's going wrong here and get your code working smoothly.

问题根源 #

The error you're hitting comes down to a core Pine Script rule: the style parameter in the plot() function requires a constant value (a fixed integer that doesn't change per bar). But your cr20style variable is a series integer—it can flip between 1 and 2 on every candlestick based on your cr20_50up condition. The interpreter is clear: it can't accept a dynamic, bar-by-bar value for this parameter.

修正方案 #

Instead of trying to pass a changing variable to style, you'll need to create two separate plot() calls—one for each style you want—and toggle their visibility using the display parameter. Here's your adjusted code:

// Assuming d1 and d9 are already defined in your script
cr20_50up = cross(d1, d9) and d1 > d9

// Plot with first style (e.g., line with breaks, matching your original "1")
plot(d1, title='%K SMA20', color=cr20_50_color, transp=0, 
     style=plot.style_linebr,
     display=cr20_50up ? display.data : display.none)

// Plot with second style (e.g., circles, matching your original "2")
plot(d1, title='%K SMA20', color=cr20_50_color, transp=0, 
     style=plot.style_circles,
     display=not cr20_50up ? display.data : display.none)

细节说明 #

• We use named style constants like plot.style_linebr and plot.style_circles instead of raw numbers—they’re far more readable and align with Pine Script’s official style definitions (you can look up all available styles in the Pine Script docs).
• The display parameter handles visibility: when cr20_50up is true, we show the first plot and hide the second; when it’s false, we flip that behavior.

进阶优化：让样式在交叉后保持不变 #

If you want the style to stay set after a cross (instead of flipping on every bar), use a var variable to track the state:

var bool cr20_state = false
// Update state only when a cross occurs
cr20_state := cross(d1, d9) ? d1 > d9 : cr20_state

plot(d1, title='%K SMA20', color=cr20_50_color, transp=0, 
     style=plot.style_linebr, 
     display=cr20_state ? display.data : display.none)

plot(d1, title='%K SMA20', color=cr20_50_color, transp=0, 
     style=plot.style_circles, 
     display=not cr20_state ? display.data : display.none)

This way, the style will only change when cross(d1,d9) triggers, and stay consistent until the next cross event.

内容的提问来源于stack exchange，提问作者scottsanpedro