Qt Quick 演示 - StocQt

/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
import QtQuick
ListModel {
    id: stocks
    // pre-fetch data for all entries
    Component.onCompleted: {
        for (var idx = 0; idx < count; ++idx) {
            getCloseValue(idx)
        }
    }
    function getCloseValue(index) {
        var endDate = new Date(); // today
        var startDate = new Date();
        endDate.setDate(startDate.getDate() - 1);
        startDate.setDate(endDate.getDate() - 7);
        var req = "data/" + get(index).stockId + ".csv"
        var xhr = new XMLHttpRequest;
        xhr.open("GET", req, true);
        xhr.onreadystatechange = function() {
            if (xhr.readyState === XMLHttpRequest.LOADING || xhr.readyState === XMLHttpRequest.DONE) {
                var records = xhr.responseText.split('\n');
                var unknown = "n/a";
                set(index, {"value": unknown, "change": unknown, "changePercentage": unknown});
                if (records.length > 0 && xhr.status == 200) {
                    var r = records[1].split(',');
                    var today = parseFloat(r[4]);
                    if (!isNaN(today))
                        setProperty(index, "value", today.toFixed(2));
                    if (records.length > 2) {
                        r = records[2].split(',');
                        var yesterday = parseFloat(r[4]);
                        var change = today - yesterday;
                        if (change >= 0.0)
                            setProperty(index, "change", "+" + change.toFixed(2));
                        else
                            setProperty(index, "change", change.toFixed(2));
                        var changePercentage = (change / yesterday) * 100.0;
                        if (changePercentage >= 0.0)
                            setProperty(index, "changePercentage", "+" + changePercentage.toFixed(2) + "%");
                        else
                            setProperty(index, "changePercentage", changePercentage.toFixed(2) + "%");
                    }
                }
            }
        }
        xhr.send()
    }
    // Uncomment to test invalid entries
    // ListElement {name: "The Qt Company"; stockId: "TQTC"; value: "999.0"; change: "0.0"; changePercentage: "0.0"}
    // Offline data downloaded using the url, https://www.quandl.com/api/v3/datasets/WIKI/<stockId>.csv.
    ListElement {name: "Advanced Micro Devices Inc."; stockId: "AMD"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Amazon.com Inc."; stockId: "AMZN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Apple Inc."; stockId: "AAPL"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Autodesk Inc."; stockId: "ADSK"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Cisco Systems Inc."; stockId: "CSCO"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "eBay Inc."; stockId: "EBAY"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Electronic Arts Inc."; stockId: "EA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Intel Corp."; stockId: "INTC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Microsoft Corp."; stockId: "MSFT"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "NetApp Inc."; stockId: "NTAP"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Netflix Inc."; stockId: "NFLX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Norwegian Cruise Line Holdings Ltd."; stockId: "NCLH"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "NVIDIA Corp."; stockId: "NVDA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "PayPal Holdings Inc."; stockId: "PYPL"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "QUALCOMM Inc."; stockId: "QCOM"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Tesla Motors Inc."; stockId: "TSLA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Texas Instruments Inc."; stockId: "TXN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
    ListElement {name: "Facebook Inc."; stockId: "FB"; value: "0.0"; change: "0.0"; changePercentage: "0.0"}
}