Convert week number to a date

MIT App Inventor Help
1

Hi,

Is anyone aware of an extension that will convert week number and year to a date ?
eg - 17 (year) 40 (week) = 8 October 2017 (last day of that week)

Or even an algorithm to calculate it.

Cheers
Steve

2

You could throw one of these at a webviewer, run javascript, and get output back with the webviewstring

Probably quicker than trying to use just blocks and the clock component.

3

Try this draggable procedure:

last_date_of_week
last_date_of_week1768×638 69.8 KB

Here is my test:
last_date_of_week_test

P.S. There will probably be a surprise when you ask for week 53, and the last date is in the next year. Should it be clipped to the starting year end?

4

Hmmmm

image
image797×494 53.9 KB

Day on which week starts (e.g here, Monday):

var weekyear = window.AppInventor.getWebViewString();
var week = weekyear.split(",")[0]; 
var year = weekyear.split(",")[1]; 
var date = new Date(year, 0, (1 + (week - 1) * 7)); 
date.setDate(date.getDate() + (1 - date.getDay())); 
window.AppInventor.setWebViewString(JSON.stringify(date));

Date:

var weekyear = window.AppInventor.getWebViewString(); 
var week = weekyear.split(",")[0]; 
var year = weekyear.split(",")[1]; 
var weekdate = (1 + (week - 1) * 7); 
date = new Date(year,0,weekdate); 
window.AppInventor.setWebViewString(JSON.stringify(date));
6

Perfect as is ....its calculating as manufacture date so is best with week 53 into the next year.