Qt Quick Demo - StocQt

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 import QtQuick 2.0

 ListModel {
     id: model
     property string stockId: ""
     property string stockName: ""
     property var newest
     property var oldest
     property bool ready: false
     property real stockPrice: 0.0
     property real stockPriceChanged: 0.0

     signal dataReady

     function indexOf(date) {
         if (model.count == 0)
             return -1;

         if (newest <= date)
             date = new Date(newest.getYear(),
                             newest.getMonth(),
                             newest.getDate() - 7);

         if (oldest >= date)
             return model.count - 1;

         var currDiff = 0;
         var bestDiff = Math.abs(date.getTime() - newest.getTime());
         var retval = 0;
         for (var i = 0; i < model.count; i++) {
             var d = new Date(model.get(i).date);
             currDiff = Math.abs(d.getTime() - date.getTime());
             if (currDiff < bestDiff) {
                 bestDiff = currDiff;
                 retval = i + 1;
             }
             if (currDiff > bestDiff)
                 return retval;
         }
         return -1;
     }

     function createStockPrice(r) {
         return {
                 "date": r[0],
                 "open":r[1],
                 "high":r[2],
                 "low":r[3],
                 "close":r[4],
                 "volume":r[5],
                };
     }

     function updateStock() {
         if (stockId === "")
             return;

         var startDate = new Date(2011, 4, 25);
         var endDate = new Date(); //today

         var req = "data/" + stockId + ".csv"
         if (!req)
             return;

         var xhr = new XMLHttpRequest;

         xhr.open("GET", req, true);

         model.ready = false;
         model.clear();
         var i = 1; //skip the first line
         xhr.onreadystatechange = function() {
             if (xhr.readyState === XMLHttpRequest.LOADING || xhr.readyState === XMLHttpRequest.DONE) {
                 var records = xhr.responseText.split('\n');
                 for (;i < records.length; i++ ) {
                     var r = records[i].split(',');
                     if (r.length >= 6)
                         model.append(createStockPrice(r));
                 }

                 if (xhr.readyState === XMLHttpRequest.DONE) {
                     if (model.count > 0) {
                         model.ready = true;
                         model.stockPrice = model.get(0).close;
                         model.stockPriceChanged = model.count > 1 ? (Math.round((model.stockPrice - model.get(1).close) * 100) / 100) : 0;
                         newest = new Date(model.get(0).date);
                         oldest = new Date(model.get(model.count - 1).date);
                     } else {
                         model.stockPrice = 0;
                         model.stockPriceChanged = 0;
                     }
                     model.dataReady(); // emit signal - model.ready indicates whether the data is valid
                 }
             }
         }
         xhr.send()
     }
 }