Hide columns based on cell value

The following code does the trick:

function onOpen() {
  // get active spreadsheet
  var ss = SpreadsheetApp.getActiveSpreadsheet();

  // create menu
  var menu = [{name: "Hide columns", functionName: "hideColumn"},
    {name: "Show all columns", functionName: "showColumn"}];

  // add to menu
  ss.addMenu("Check", menu);
}

function hideColumn() {
  // get active spreadsheet
  var ss = SpreadsheetApp.getActiveSpreadsheet();

  // get first sheet
  var sheet = ss.getSheets()[0];

  // get data
  var data = sheet.getDataRange();

  // get number of columns
  var lastCol = data.getLastColumn()+1;

  Logger.log(lastCol);

  // itterate through columns
  for(var i=1; i<lastCol; i++) {
     if(data.getCell(3, i).getValue() == '') {
        sheet.hideColumns(i);
     }
  }
}

function showColumn() {
  // get active spreadsheet
  var ss = SpreadsheetApp.getActiveSpreadsheet();

  // get first sheet
  var sheet = ss.getSheets()[0];

  // get data
  var data = sheet.getDataRange();

  // get number of columns
  var lastCol = data.getLastColumn();

  // show all columns
  sheet.showColumns(1, lastCol);
}

1. Creates menu upon opening file
2. First menu option, hides all columns with row 3 being empty
3. Second option, shows all hidden columns

See example file I prepared to watch it in action: Hide columns based on cell value