main.qml Example File

qmlweather/qml/qmlweather/main.qml
 /****************************************************************************
 **
 ** Copyright (C) 2016 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the Qt Charts module of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:GPL$
 ** Commercial License Usage
 ** Licensees holding valid commercial Qt licenses may use this file in
 ** accordance with the commercial license agreement provided with the
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 ** information use the contact form at https://www.qt.io/contact-us.
 **
 ** GNU General Public License Usage
 ** Alternatively, this file may be used under the terms of the GNU
 ** General Public License version 3 or (at your option) any later version
 ** approved by the KDE Free Qt Foundation. The licenses are as published by
 ** the Free Software Foundation and appearing in the file LICENSE.GPL3
 ** included in the packaging of this file. Please review the following
 ** information to ensure the GNU General Public License requirements will
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 import QtQuick 2.0
 import QtCharts 2.0

 Rectangle {
     width: 500
     height: 400
     gradient: Gradient {
         GradientStop { position: 0.0; color: "lightblue" }
         GradientStop { position: 1.0; color: "white" }
     }

     ChartView {
         id: chartView
         title: "Weather forecast"
         height: parent.height / 4 * 3
         anchors.top: parent.top
         anchors.left: parent.left
         anchors.right: parent.right
         legend.alignment: Qt.AlignTop
         antialiasing: true

         BarCategoryAxis {
             id: barCategoriesAxis
             titleText: "Date"
         }

         ValueAxis{
             id: valueAxisY2
             min: 0
             max: 10
             titleText: "Rainfall [mm]"
         }

         ValueAxis {
             id: valueAxisX
             // Hide the value axis; it is only used to map the line series to bar categories axis
             visible: false
             min: 0
             max: 5
         }

         ValueAxis{
             id: valueAxisY
             min: 0
             max: 15
             titleText: "Temperature [°C]"
         }

         LineSeries {
             id: maxTempSeries
             axisX: valueAxisX
             axisY: valueAxisY
             name: "Max. temperature"
         }

         LineSeries {
             id: minTempSeries
             axisX: valueAxisX
             axisY: valueAxisY
             name: "Min. temperature"
         }

         BarSeries {
             id: myBarSeries
             axisX: barCategoriesAxis
             axisYRight: valueAxisY2
             BarSet {
                 id: rainfallSet
                 label: "Rainfall"
             }
         }
     }

     // A timer to refresh the forecast every 5 minutes
     Timer {
         interval: 300000
         repeat: true
         triggeredOnStart: true
         running: true
         onTriggered: {
             if (weatherAppKey != "") {
                 // Make HTTP GET request and parse the result
                 var xhr = new XMLHttpRequest;
                 xhr.open("GET",
                          "http://free.worldweatheronline.com/feed/weather.ashx?q=Jyv%c3%a4skyl%c3%a4,Finland&format=json&num_of_days=5&key="
                          + weatherAppKey);
                 xhr.onreadystatechange = function() {
                     if (xhr.readyState == XMLHttpRequest.DONE) {
                         var a = JSON.parse(xhr.responseText);
                         parseWeatherData(a);
                     }
                 }
                 xhr.send();
             } else {
                 // No app key for worldweatheronline.com given by the user -> use dummy static data
                 var responseText = "{ \"data\": { \"current_condition\": [ {\"cloudcover\": \"10\", \"humidity\": \"61\", \"observation_time\": \"06:26 AM\", \"precipMM\": \"0.0\", \"pressure\": \"1022\", \"temp_C\": \"6\", \"temp_F\": \"43\", \"visibility\": \"10\", \"weatherCode\": \"113\",  \"weatherDesc\": [ {\"value\": \"Sunny\" } ],  \"weatherIconUrl\": [ {\"value\": \"http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0001_sunny.png\" } ], \"winddir16Point\": \"SE\", \"winddirDegree\": \"140\", \"windspeedKmph\": \"7\", \"windspeedMiles\": \"4\" } ],  \"request\": [ {\"query\": \"Jyvaskyla, Finland\", \"type\": \"City\" } ],  \"weather\": [ {\"date\": \"2012-05-09\", \"precipMM\": \"0.4\", \"tempMaxC\": \"14\", \"tempMaxF\": \"57\", \"tempMinC\": \"7\", \"tempMinF\": \"45\", \"weatherCode\": \"116\",  \"weatherDesc\": [ {\"value\": \"Partly Cloudy\" } ],  \"weatherIconUrl\": [ {\"value\": \"http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0002_sunny_intervals.png\" } ], \"winddir16Point\": \"S\", \"winddirDegree\": \"179\", \"winddirection\": \"S\", \"windspeedKmph\": \"20\", \"windspeedMiles\": \"12\" }, {\"date\": \"2012-05-10\", \"precipMM\": \"2.4\", \"tempMaxC\": \"13\", \"tempMaxF\": \"55\", \"tempMinC\": \"8\", \"tempMinF\": \"46\", \"weatherCode\": \"266\",  \"weatherDesc\": [ {\"value\": \"Light drizzle\" } ],  \"weatherIconUrl\": [ {\"value\": \"http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0017_cloudy_with_light_rain.png\" } ], \"winddir16Point\": \"SW\", \"winddirDegree\": \"219\", \"winddirection\": \"SW\", \"windspeedKmph\": \"21\", \"windspeedMiles\": \"13\" }, {\"date\": \"2012-05-11\", \"precipMM\": \"11.1\", \"tempMaxC\": \"15\", \"tempMaxF\": \"59\", \"tempMinC\": \"7\", \"tempMinF\": \"44\", \"weatherCode\": \"266\",  \"weatherDesc\": [ {\"value\": \"Light drizzle\" } ],  \"weatherIconUrl\": [ {\"value\": \"http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0017_cloudy_with_light_rain.png\" } ], \"winddir16Point\": \"SSW\", \"winddirDegree\": \"200\", \"winddirection\": \"SSW\", \"windspeedKmph\": \"20\", \"windspeedMiles\": \"12\" }, {\"date\": \"2012-05-12\", \"precipMM\": \"2.8\", \"tempMaxC\": \"7\", \"tempMaxF\": \"44\", \"tempMinC\": \"2\", \"tempMinF\": \"35\", \"weatherCode\": \"317\",  \"weatherDesc\": [ {\"value\": \"Light sleet\" } ],  \"weatherIconUrl\": [ {\"value\": \"http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0021_cloudy_with_sleet.png\" } ], \"winddir16Point\": \"NW\", \"winddirDegree\": \"311\", \"winddirection\": \"NW\", \"windspeedKmph\": \"24\", \"windspeedMiles\": \"15\" }, {\"date\": \"2012-05-13\", \"precipMM\": \"0.4\", \"tempMaxC\": \"6\", \"tempMaxF\": \"42\", \"tempMinC\": \"2\", \"tempMinF\": \"35\", \"weatherCode\": \"116\",  \"weatherDesc\": [ {\"value\": \"Partly Cloudy\" } ],  \"weatherIconUrl\": [ {\"value\": \"http:\/\/www.worldweatheronline.com\/images\/wsymbols01_png_64\/wsymbol_0002_sunny_intervals.png\" } ], \"winddir16Point\": \"WNW\", \"winddirDegree\": \"281\", \"winddirection\": \"WNW\", \"windspeedKmph\": \"21\", \"windspeedMiles\": \"13\" } ] }}";
                 var a = JSON.parse(responseText);
                 parseWeatherData(a);
             }
         }
     }

     Row {
         id: weatherImageRow
         anchors.top: chartView.bottom
         anchors.topMargin: 5
         anchors.bottom: poweredByText.top
         anchors.bottomMargin: 5
         anchors.horizontalCenter: parent.horizontalCenter
         height: parent.height - chartView.height - anchors.topMargin

         ListModel {
             id: weatherImageModel
         }

         Repeater {
             id: repeater
             model: weatherImageModel
             delegate: Image {
                 source: imageSource
                 width: weatherImageRow.height
                 height: width
                 fillMode: Image.PreserveAspectCrop
             }
         }
     }

     Text {
         id: poweredByText
         anchors.bottom: parent.bottom
         anchors.bottomMargin: 5
         anchors.left: parent.left
         anchors.leftMargin: 25
         height: parent.height / 25
         text: "Powered by World Weather Online"
     }

     function parseWeatherData(weatherData) {
         // Clear previous values
         maxTempSeries.clear();
         minTempSeries.clear();
         weatherImageModel.clear();

         // Loop through the parsed JSON
         for (var i in weatherData.data.weather) {
             var weatherObj = weatherData.data.weather[i];

             // Store temperature values, rainfall and weather icon.
             // The temperature values begin from 0.5 instead of 0.0 to make the start from the
             // middle of the rainfall bars. This makes the temperature lines visually better
             // synchronized with the rainfall bars.
             maxTempSeries.append(Number(i) + 0.5, weatherObj.tempMaxC);
             minTempSeries.append(Number(i) + 0.5, weatherObj.tempMinC);
             rainfallSet.append(i, weatherObj.precipMM);
             weatherImageModel.append({"imageSource":weatherObj.weatherIconUrl[0].value});

             // Update scale of the chart
             valueAxisY.max = Math.max(chartView.axisY().max,weatherObj.tempMaxC);
             valueAxisX.min = 0;
             valueAxisX.max = Number(i) + 1;

             // Set the x-axis labels to the dates of the forecast
             var xLabels = barCategoriesAxis.categories;
             xLabels[Number(i)] = weatherObj.date.substring(5, 10);
             barCategoriesAxis.categories = xLabels;
             barCategoriesAxis.visible = true;
             barCategoriesAxis.min = 0;
             barCategoriesAxis.max = xLabels.length - 1;
         }
     }

 }