Google App Script - Conditional Formatting Based on Another Cell

Question

I am trying to figure out how to use conditional formatting via script on a google spreadsheet similar to what you can do with the conditional formatting feature.

I have

Answer 1

Try copy and pasting this into a blank script file. This depends on column A being Country, and column B being State, but you can make as many sheets as you want, and this will work automatically.

Let me know if you want an explanation of a specific part, as I'm not sure what your scripting background is. I've included some comments in the code.

function onEdit(e) {

  var ss = e.source;
  var sheet = ss.getActiveSheet();
  var range = sheet.getRange("A:B");
  var values = range.getValues();

  //for each row that data is present
  for(var i = 0; i < values.length; i++) {
    var cell = sheet.getRange(i + 1, 2);

    //check if the first value of that row is exactly "United States"
    if(values[i][0] === "United States") {

      //if it is, check for a blank cell.  If so, make it red.
      if(values[i][1] === "") {
        cell.setBackground('red');
      } else {
        cell.setBackground('white');
      }

    } else {

      //In any other case, make it white.
      cell.setBackground('white');
    }
  }  
}    

Answer 2

Let's assume that Country is placed at (1,1) and State is placed at (1,2) where (i,j) indicates the ith row and jth column on the Spreadsheet. Google Spreadsheets is 1-indexed meaning indices start at 1.

var activeSheet = SpreadsheetApp.getActiveSheet();

for (var a = 2; a < activeSheet.getLastRow(); a++) {
   if (String(activeSheet.getRange(a,1).getCell(1,1)) === "United States") { 
       if (String(activeSheet.getRange(a,2).getCell(1,1)) === null) { 
          activeSheet.getRange(a, 2, 1, 1).setBackgroundColor('red'); 
       } 
   } 
}