017_IntroToAppsScript_addingFormulas.js

// add total for each row into our Sheet
function addRowTotals() {
  
  const ss = SpreadsheetApp.getActive();
  const sheet1 = ss.getSheetByName('Sheet1');
  const lastRow = sheet1.getLastRow();
  
  const data = sheet1.getRange(2,1,lastRow - 1,3).getValues();

  console.log(data); 
  
  const totalsArray = [];
  
  data.forEach(function(row) {
    
    const name = row[0];
    const cost = row[1];
    const quantity = row[2];
    
    const total = cost * quantity;
    
    row.push(total);
    
    totalsArray.push([total]);
    
    console.log(row);
    
  });
  
  console.log(totalsArray);
  
  // paste data back into Sheet
  sheet1.getRange(2,4,lastRow - 1,1).setValues(totalsArray);

}


// add menu
// onOpen is a special function
// runs when your Sheet opens
function onOpen() {
  
  const ui = SpreadsheetApp.getUi();
  
  ui.createMenu('Custom Menu')
    .addItem('Add Row Totals','addRowTotals')
    .addItem('Add Grand Total','grandTotal')
    .addToUi();
  
}


// add grand total function
function grandTotal() {

  const ss = SpreadsheetApp.getActiveSpreadsheet();
  const sheet1 = ss.getSheetByName('Sheet1');
  const lastRow = sheet1.getLastRow();
  const lastColumn = sheet1.getLastColumn();

  // add total row
  sheet1.getRange(lastRow + 1,1).setValue('TOTAL');
  sheet1.getRange(lastRow + 1, lastColumn).setFormula('=SUM(D2:D' + lastRow + ')');

}