如何将rgba转换成hex?

我认为roku中没有api,所以我只是编写了一个函数。

// Example: If you input (255, 255, 255, 255) as the argument it will return "0xFFFFFFFF"

function rgbaToHex(r as integer, g as integer, b as integer, a as integer)
    hexArray = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"]
    hexColor = "0x"

    for i = 0 to 3
        colorChannel = invalid

        if(i = 0) then
            colorChannel = r

        else if(i = 1) then
            colorChannel = g

        else if(i=2) then  
            colorChannel = b

        else if(i=3) then
            colorChannel = a
        end if

        sixteens = int(colorChannel / 16)  // How many 16's can go into colorChannel (since hex is base 16)?
        ones = colorChannel mod 16         // How many 1's are in the remainder?

        hexColor += hexArray[sixteens] + hexArray[ones]
    end for

    return hexColor
end function

您也可以使用位移位,它不会按要求返回十六进制,但会返回一个可以使用的颜色值

颜色=(R<<24)+(G<<16)+(B<<8)+A