Google Sheets - Script Slow - Dependent Dropdown - google-apps-script

Question

I have three dropdown boxes that are dependent on each other. The code works fine but is really slow, 3 seconds to update the next box. I'm used to VBA and this is no problem in Excel, but it's really show in Google Sheets. I added a Browser.msgBox("here"); to the first line of the code and from changing the dropdown it takes 2 seconds to display it. This can't be normal?
Here's the code: (The list options are stored in Named Ranges, the correct name is generated and stored in the optName below )
function onEdit(event) {
if (!event) return;
//SETTINGS
var ss = event.source;
var sheet = event.source.getActiveSheet();
var r = event.source.getActiveRange();
var sheetName = sheet.getName()
if(sheet.getName() == 'Damages & Repairs July 2018') {
var lcol = 3; // leftmost column number you are monitoring
var rcol =6; // rightmost column number you are monitoring
}else{
var lcol = 4; // leftmost column number you are monitoring
var rcol =7; // rightmost column number you are monitorin
}
//
if (sheetName == 'Refunds July 2018' || sheetName == 'Exchanges July 2018'|| sheetName == 'Damages & Repairs July 2018') {
var sourceCol = r.getColumn();
var sourceRow = r.getRow();
var ss = SpreadsheetApp.getActiveSpreadsheet();
if(sheetName == 'Damages & Repairs July 2018') {
if(sourceCol == 4) {
var optName = sheet.getRange(sourceRow, lcol ).getValue() + sheet.getRange(sourceRow, lcol + 1).getValue();
} else if ( sourceCol == 5) {
var optName = sheet.getRange(sourceRow, lcol + 1).getValue();
} else {
var optName = sheet.getRange(sourceRow, sourceCol).getValue();
}
} else {
if(sourceCol == 5) {
var optName = sheet.getRange(sourceRow, lcol ).getValue() + sheet.getRange(sourceRow, lcol + 1).getValue();
} else if ( sourceCol == 6) {
var optName = sheet.getRange(sourceRow, lcol + 1).getValue();
} else {
var optName = sheet.getRange(sourceRow, sourceCol).getValue();
}
}
var optName = optName.replace(/\s/g, "");
var tableRange = ss.getRangeByName(optName).getValues();
var optList = "";
if (sourceCol >= lcol && sourceCol <= rcol) {
// define the dropdown/validation rules
var rangeRule = SpreadsheetApp.newDataValidation().requireValueInList(tableRange);
// Clear the validation
//sheet.getRange(sourceRow, sourceCol + 1).clearDataValidations()
//sheet.getRange(sourceRow, sourceCol + 1).clearContent()
// set the dropdown validation for the row
sheet.getRange(sourceRow, sourceCol + 1).setDataValidation(rangeRule); // set range to your range
}
}
}
Any help would be very much appreciated.
Thanks
Chris
UPDATE
I changed the code to this - but still not that much faster:
function onEdit(event) {
//SETTINGS
var ss = event.source;
var sheet = event.source.getActiveSheet();
var r = event.source.getActiveRange();
var sheetName = sheet.getName();
var sourceCol = r.getColumn();
var sourceRow = r.getRow();
if(sheet.getName() == 'Damages & Repairs July 2018') {
var lcol = 3; // leftmost column number you are monitoring
var rcol =6; // rightmost column number you are monitoring
}else{
var lcol = 4; // leftmost column number you are monitoring
var rcol =7; // rightmost column number you are monitorin
}
var sourceRange = sheet.getRange('R' + sourceRow + 'C' + lcol + ':R' + sourceRow + 'C' + rcol).getValues();
if (sheetName == 'Refunds July 2018' || sheetName == 'Exchanges July 2018'|| sheetName == 'Damages & Repairs July 2018') {
var ss = SpreadsheetApp.getActiveSpreadsheet();
if(sheetName == 'Damages & Repairs July 2018') {
if(sourceCol == 4) {
var optName = sourceRange[0][0] + sourceRange[0][1];
} else if ( sourceCol == 5) {
var optName = sourceRange[0][1];
} else {
var optName =sourceRange[0][0];
}
} else {
if(sourceCol == 5) {
var optName = sourceRange[0][0] + sourceRange[0][1];
} else if ( sourceCol == 6) {
var optName = sourceRange[0][1];
} else {
var optName = sourceRange[0][0];
}
}
var optName = optName.replace(/\s/g, "");
var tableRange = ss.getRangeByName(optName).getValues();
var optList = "";
if (sourceCol >= lcol && sourceCol <= rcol) {
// define the dropdown/validation rules
var rangeRule = SpreadsheetApp.newDataValidation().requireValueInList(tableRange);
// Clear the validation
sheet.getRange(sourceRow, sourceCol + 1).clearDataValidations()
sheet.getRange(sourceRow, sourceCol + 1).clearContent()
// set the dropdown validation for the row
sheet.getRange(sourceRow, sourceCol + 1).setDataValidation(rangeRule); // set range to your range
}
}
}