Google Apps Script working with selection - google-apps-script

Question

I would like to add a menu item to a Google Sheet that performs a task on the selected cells. A web search, including Stack Overflow, indicates that the getActiveRange() method is the proper approach. But when I query the returned Range object, regardless of what cells I have selected, it always reports the first row equal to 1 and the number of rows equal to 1. What should I be using?
Here is a stripped-down script that reproduces the issue:
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheets()[0];
function onOpen() {
var myMenu = [];
myMenu.push({name: "Detect selection", functionName: "detectSelection"});
ss.addMenu("My Menu", myMenu);
}
function detectSelection() {
var range = sheet.getActiveRange();
var firstRow = range.getRow();
var lastRow = range.getLastRow();
var numRows = range.getNumRows();
sheet.getRange(1,1).setValue("First Row");
sheet.getRange(1,2).setValue(firstRow);
sheet.getRange(2,1).setValue("Last Row");
sheet.getRange(2,2).setValue(lastRow);
sheet.getRange(3,1).setValue("Number of Rows");
sheet.getRange(3,2).setValue(numRows);
}
I can select any group of cells I wish, choose "Detect selection" from "My Menu", and the first row, last row, and number of rows will always be reported as 1.

Answer 1

Try this:
Compare it to what you have and I think you can figure it out for yourself. The learning experience will be worth it. You can select any range you want.
function runOne() {
var ss=SpreadsheetApp.getActiveSpreadsheet();
var sh=ss.getSheetByName('Sheet1');
var rg=sh.getActiveRange();
sh.clearContents();
var vA=[['rg.getRow()',rg.getRow()],['rg.getColumn()',rg.getColumn()],['rg.getLastRow()',rg.getLastRow()],['rg.getLastColumn()',rg.getLastColumn()],['rg.getNumRows()',rg.getNumRows()],['rg.getNumColumns()',rg.getNumColumns()]];
var vB=[];
for(var i=0;i<rg.getHeight();i++) {
vB[i]=[];
for(var j=0;j<rg.getWidth();j++) {
vB[i][j]=Utilities.formatString('%s,%s',rg.getRow()+i,rg.getColumn()+j);
}
}
sh.getRange(rg.getRow(),rg.getColumn(),vB.length,vB[0].length).setValues(vB);
sh.getRange(sh.getLastRow()+1,rg.getColumn(),vA.length,vA[0].length).setValues(vA);
}