To @Jacob's claim of impossibility, I refute it thus... (but thanks for the improved speed)
using:
=sumIfBgColor("#ffffff", A1:A10, COLUMN(A1), ROW(A1))
with the following functions will do what you want.
/**
* Sums cell values in a range if they have the given background color
*
* @param {String} color Hex string of color eg ("#ffffff")
* @param {Array.Array} range Values of the desired range
* @param {int} startcol The column of the range
* @param {int} startrow The first row of the range
*
* @return {int} Sum of all cell values matching the condition
*/
function sumIfBgColor(color, range, startcol, startrow){
// convert from int to ALPHANUMERIC - thanks to
// Daniel at http://stackoverflow.com/a/3145054/2828136
var col_id = String.fromCharCode(64 + startcol);
var endrow = startrow + range.length - 1
// build the range string, then get the background colours
var range_string = col_id + startrow + ":" + col_id + endrow
var ss = SpreadsheetApp.getActiveSpreadsheet();
var getColors = ss.getRange(range_string).getBackgrounds();
var x = 0;
for(var i = 0; i < range.length; i++) {
for(var j = 0; j < range[0].length; j++) {
// Sometimes the cell background is eg 'white' rather than '#ffffff'.
// I don't know why - I think it's a bug.
// so we remove that inconsistency with colourNameToHex
// courtesy of Greg at http://stackoverflow.com/a/1573141/2828136
if(colourNameToHex(getColors[i][j].toString()) == color) {
x += range[i][j];
}
}
}
return x;
}
/**
* Takes a colour string and returns it to a hex string. If a non-matching string is
* passed, it will return the argument as is - for this situation it means that a
* hex string can be passed to it and be returned as is. This is not for production.
*
* @param {string} color Must be either a colour name or hex string of color eg ("#ffffff")
*
* @return {object|string} hex string of color eg ("#ffffff") or the argument given.
*/
function colourNameToHex(colour)
{
var colours = {"aliceblue":"#f0f8ff","antiquewhite":"#faebd7","aqua":"#00ffff","aquamarine":"#7fffd4","azure":"#f0ffff",
"beige":"#f5f5dc","bisque":"#ffe4c4","black":"#000000","blanchedalmond":"#ffebcd","blue":"#0000ff","blueviolet":"#8a2be2","brown":"#a52a2a","burlywood":"#deb887",
"cadetblue":"#5f9ea0","chartreuse":"#7fff00","chocolate":"#d2691e","coral":"#ff7f50","cornflowerblue":"#6495ed","cornsilk":"#fff8dc","crimson":"#dc143c","cyan":"#00ffff",
"darkblue":"#00008b","darkcyan":"#008b8b","darkgoldenrod":"#b8860b","darkgray":"#a9a9a9","darkgreen":"#006400","darkkhaki":"#bdb76b","darkmagenta":"#8b008b","darkolivegreen":"#556b2f",
"darkorange":"#ff8c00","darkorchid":"#9932cc","darkred":"#8b0000","darksalmon":"#e9967a","darkseagreen":"#8fbc8f","darkslateblue":"#483d8b","darkslategray":"#2f4f4f","darkturquoise":"#00ced1",
"darkviolet":"#9400d3","deeppink":"#ff1493","deepskyblue":"#00bfff","dimgray":"#696969","dodgerblue":"#1e90ff",
"firebrick":"#b22222","floralwhite":"#fffaf0","forestgreen":"#228b22","fuchsia":"#ff00ff",
"gainsboro":"#dcdcdc","ghostwhite":"#f8f8ff","gold":"#ffd700","goldenrod":"#daa520","gray":"#808080","green":"#008000","greenyellow":"#adff2f",
"honeydew":"#f0fff0","hotpink":"#ff69b4",
"indianred ":"#cd5c5c","indigo ":"#4b0082","ivory":"#fffff0","khaki":"#f0e68c",
"lavender":"#e6e6fa","lavenderblush":"#fff0f5","lawngreen":"#7cfc00","lemonchiffon":"#fffacd","lightblue":"#add8e6","lightcoral":"#f08080","lightcyan":"#e0ffff","lightgoldenrodyellow":"#fafad2",
"lightgrey":"#d3d3d3","lightgreen":"#90ee90","lightpink":"#ffb6c1","lightsalmon":"#ffa07a","lightseagreen":"#20b2aa","lightskyblue":"#87cefa","lightslategray":"#778899","lightsteelblue":"#b0c4de",
"lightyellow":"#ffffe0","lime":"#00ff00","limegreen":"#32cd32","linen":"#faf0e6",
"magenta":"#ff00ff","maroon":"#800000","mediumaquamarine":"#66cdaa","mediumblue":"#0000cd","mediumorchid":"#ba55d3","mediumpurple":"#9370d8","mediumseagreen":"#3cb371","mediumslateblue":"#7b68ee",
"mediumspringgreen":"#00fa9a","mediumturquoise":"#48d1cc","mediumvioletred":"#c71585","midnightblue":"#191970","mintcream":"#f5fffa","mistyrose":"#ffe4e1","moccasin":"#ffe4b5",
"navajowhite":"#ffdead","navy":"#000080",
"oldlace":"#fdf5e6","olive":"#808000","olivedrab":"#6b8e23","orange":"#ffa500","orangered":"#ff4500","orchid":"#da70d6",
"palegoldenrod":"#eee8aa","palegreen":"#98fb98","paleturquoise":"#afeeee","palevioletred":"#d87093","papayawhip":"#ffefd5","peachpuff":"#ffdab9","peru":"#cd853f","pink":"#ffc0cb","plum":"#dda0dd","powderblue":"#b0e0e6","purple":"#800080",
"red":"#ff0000","rosybrown":"#bc8f8f","royalblue":"#4169e1",
"saddlebrown":"#8b4513","salmon":"#fa8072","sandybrown":"#f4a460","seagreen":"#2e8b57","seashell":"#fff5ee","sienna":"#a0522d","silver":"#c0c0c0","skyblue":"#87ceeb","slateblue":"#6a5acd","slategray":"#708090","snow":"#fffafa","springgreen":"#00ff7f","steelblue":"#4682b4",
"tan":"#d2b48c","teal":"#008080","thistle":"#d8bfd8","tomato":"#ff6347","turquoise":"#40e0d0",
"violet":"#ee82ee",
"wheat":"#f5deb3","white":"#ffffff","whitesmoke":"#f5f5f5",
"yellow":"#ffff00","yellowgreen":"#9acd32"};
if (typeof colours[colour.toLowerCase()] != 'undefined')
return colours[colour.toLowerCase()];
return colour;
}
Best Answer
Short answer
Google Sheets pass custom function arguments as values, not as objects, in this case not as a cell/range.
Workaround
Use SpreadsheetApp.getActiveRange().getFormula() to get the cell formula and extract the reference from it.
Example
Note: Custom functions recalculates when their arguments changes their values. Changing the background of the referenced cell will not make that Google Sheets recalculate them.
Explanation
In the Google Sheets / Google Apps Script argot, user-defined functions are called custom functions.
From the custom functions official documentation:
IMHO the documentation should include a note regarding cell/range references as the Spreadsheet service includes Range as class.