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Qt5官方demo解析集31——StocQt
本系列所有文章可以在这里查看http://blog.csdn.net/cloud_castle/article/category/2123873
接上文Qt5官方demo解析集30——Extending QML - Binding Example
最近在做QML制表,因此想找一些相关曲线绘制的demo看看,结果发现了这个例子,觉得挺不错,它相比于我们之前的Extend和Particle系列显得更大一些,涉及到的面也更广一些。因此想拿过来给大家分享~
这个例子是基于QML的股票走势图绘制,数据来源于yahoo的纳达克斯-100指数,向左滑动可以选择股票。
曲线页面:
列表页面:
工程目录如下:
这个例子的结构会稍微复杂一些,我建议大家在QtCreator中将这个例子打开,这样有什么想法或是疑虑时我们可以将代码改改,或是添加一些输出信息,举一反三的学习总是比较有效的。
ok,我们自顶而下的跟着调用的顺序来:
stocqt.qml:
import QtQuick 2.0 import QtQml.Models 2.1 import "./content" // 添加其他qml文件路径 Rectangle { id: mainRect width: 1000 height: 700 property int listViewActive: 0 // 该页面实际是一个ListView的一部分,这个属性用来表明前面的列表页面是否被激活 Rectangle { // 导航栏 id: banner height: 80 anchors.top: parent.top width: parent.width color: "#000000" Image { id: arrow source: "./content/images/icon-left-arrow.png" anchors.left: banner.left anchors.leftMargin: 20 anchors.verticalCenter: banner.verticalCenter visible: root.currentIndex == 1 ? true : false // 曲线页面是ListView的第二个页面,currentIndex的值也就是1 MouseArea { anchors.fill: parent onClicked: listViewActive = 1; } } Item { // 将相关组件放在一个Item容器中 id: textItem width: stocText.width + qtText.width // 容器的尺寸由组件决定 height: stocText.height + qtText.height anchors.horizontalCenter: banner.horizontalCenter anchors.verticalCenter: banner.verticalCenter Text { // Stoc id: stocText anchors.verticalCenter: textItem.verticalCenter color: "#ffffff" font.family: "Abel" font.pointSize: 40 text: "Stoc" } Text { // Qt id: qtText anchors.verticalCenter: textItem.verticalCenter anchors.left: stocText.right color: "#5caa15" font.family: "Abel" font.pointSize: 40 text: "Qt" } } } ListView { // 标题栏下方则是ListView的内容,它为列表页面与曲线页面提供了滑动切换的能力 id: root width: parent.width anchors.top: banner.bottom anchors.bottom: parent.bottom snapMode: ListView.SnapOneItem // 设置该属性使View停止在一个完整的页面上 highlightRangeMode: ListView.StrictlyEnforceRange highlightMoveDuration: 250 // 这里设置了一个无形的高亮,它不显示,但提供了0.25秒的切换动画 focus: false orientation: ListView.Horizontal boundsBehavior: Flickable.StopAtBounds // 滑动时停在边界,默认可以拉拽更远并在弹回时带有超调效果 currentIndex: listViewActive == 0 ? 1 : 0 // 使用属性绑定,当listViewActive被激活时,使currentIndex置0,从而跳转到列表页面 onCurrentIndexChanged: { if (currentIndex == 1) listViewActive = 0; } StockModel { // 初始化数据模型 id: stock stockId: listView.currentStockId // 注意这个listView不是其父ListView,而是下面那个,即列表页面 stockName: listView.currentStockName // 列表页面将当前所选的股票ID及名字赋给StockModel,使其取得相应的数据 onStockIdChanged: stock.updateStock(); // 当ID改变时数据更新 onDataReady: { console.log(listView.currentStockId, listView.currentStockName) root.positionViewAtIndex(1, ListView.SnapPosition) // 上面的高亮即为这里的ListView.SnapPosition做准备,数据变更后切换到曲线页面,带有0.25秒的过渡动画 stockView.update() // 页面更新 } } model: ObjectModel { // ObjectModel源自上面import的Qt.QML.Model 2.1,它使得ListView可以使用组件列表作为模型,适用于多个完全不相似的组件 StockListView { // 列表页面 id: listView width: root.width height: root.height } StockView { // 曲线页面 id: stockView width: root.width height: root.height stocklist: listView stock: stock } } } }
StockModel.qml:
import QtQuick 2.0 ListModel { // ListModel作为根项目,自定义属性作为接口,并定义了多个函数。但他本身在初始化时并不进行运算 id: model property string stockId: "" // 股票ID property string stockName: "" // 股票名 property string stockDataCycle: "d" // 数据周期 property bool ready: false // 标志位 property real stockPrice: 0.0 // 股票价格 property real stockPriceChanged: 0.0 // 价格变化 signal dataReady // 耗时的数据类通常需要定义这个信号 function indexOf(date) { // 返回从特定date的数据在数据集中的位置 var newest = new Date(model.get(0).date); // 获取第一个数据对象的日期 var oldest = new Date(model.get(model.count - 1).date); // 最后一个数据对象的日期 if (newest <= date) return -1; // 在最新日期之后直接返回 if (oldest >= date) return model.count - 1; // 在最先日期之前全部返回 var currDiff = 0; var bestDiff = Math.abs(date.getTime() - newest.getTime()); var retval = 0; // 返回变量 for (var i = 0; i < model.count; i++) { var d = new Date(model.get(i).date); currDiff = Math.abs(d.getTime() - date.getTime()); // 计算时间差值 if (currDiff < bestDiff) { // 从最新时间向目标时间推进 bestDiff = currDiff; retval = i; // retval记录数据位置 } if (currDiff > bestDiff) // 当达到目标时间后 return retval; // 将数据位置返回 } return -1; } function requestUrl() { // 创建请求数据的url字符串函数 if (stockId === "") return; var startDate = new Date(2011, 4, 25); // 指定一个开始时间 var endDate = new Date(); // 结束时间为当前时间 if (stockDataCycle !== "d" && stockDataCycle !== "w" && stockDataCycle !== "m") stockDataCycle = "d"; // 如果数据周期不是'天'、'周'、'月',则定义为'天' /* // 注释给出了向yahoo请求数据的格式 Fetch stock data from yahoo finance: url: http://ichart.finance.yahoo.com/table.csv?s=NOK&a=5&b=11&c=2010&d=7&e=23&f=2010&g=d&ignore=.csv s:stock name/id, a:start day, b:start month, c:start year default: 25 April 1995, oldest c= 1962 d:end day, e:end month, f:end year, default:today (data only available 3 days before today) g:data cycle(d daily, w weekly, m monthly, v Dividend) */ var request = "http://ichart.finance.yahoo.com/table.csv?"; request += "s=" + stockId; request += "&a=" + startDate.getMonth(); request += "&b=" + startDate.getDate(); request += "&c=" + startDate.getFullYear(); request += "&d=" + endDate.getMonth(); request += "&e=" + endDate.getDate(); request += "&f=" + endDate.getFullYear(); request += "&g=" + stockDataCycle; request += "&ignore=.csv"; return request; // 返回这一长串url } function createStockPrice(r) { // 存储数据对象函数 return { // 用来接收下面分离的7位数据,以类似结构体的形式存储下来 "date": r[0], // 这也是该model真正存储的数据类型格式 "open":r[1], "high":r[2], "low":r[3], "close":r[4], "volume":r[5], "adjusted":r[6] }; } function updateStock() { // 数据更新 var req = requestUrl(); // 得到请求数据的url字符串 if (!req) return; var xhr = new XMLHttpRequest; // 创建一个XMLHttp的请求对象 xhr.open("GET", req, true); // 初始化请求参数,还未发送请求 model.ready = false; // 标志位置false model.clear(); // 数据清空 var i = 1; // 输出一下调试信息可知,返回的数据第一行为描述符,因此将其跳过 xhr.onreadystatechange = function() { // readyState是XMLHttpRequest的一个属性,其值从0变化到4 if (xhr.readyState === XMLHttpRequest.LOADING || xhr.readyState === XMLHttpRequest.DONE) { var records = xhr.responseText.split('\n'); // LOADING为3,DONE为4,分别表示数据正在载入和载入完成 // 以换行符分割数据 for (;i < records.length; i++ ) { var r = records[i].split(','); // 以逗号将数据分割 if (r.length === 7) // 数据校验 model.append(createStockPrice(r)); // 函数调用,向model中添加数据 } if (xhr.readyState === XMLHttpRequest.DONE) { if (model.count > 0) { model.ready = true; model.stockPrice = model.get(0).adjusted; // 将最新的的调整收盘价赋予stockPrice model.stockPriceChanged = model.count > 1 ? (Math.round((model.stockPrice - model.get(1).close) * 100) / 100) : 0; // 相比前一天的收盘价变化率 model.dataReady(); //emit signal } } } } xhr.send() // 实际发出数据请求 } }我们将records的数据部分贴出来:
实际的数据被‘\n‘分开,也就是说,类似下面这个样子:
Data,Open,High,Low,Close,Volume,Adj Close,
2014-7-28,97.82,99.24,97.55,99.02,55239000,99.02,
2014-7-25 ......(7-26,7-27?周末休市啦......)
为了得到各股的变化率等,StockListView也采取了类似的实现方式:
StockListView.qml:
import QtQuick 2.0 Rectangle { id: root width: 320 height: 410 anchors.top: parent.top anchors.bottom: parent.bottom color: "white" property string currentStockId: "" property string currentStockName: "" ListView { id: view anchors.fill: parent width: parent.width clip: true // clip以延时加载数据 keyNavigationWraps: true highlightMoveDuration: 0 focus: true snapMode: ListView.SnapToItem model: StockListModel{} // 定义model function requestUrl(stockId) { // 最近5天的url创建函数,与StockModel不同的是,由于未定义stockId属性,它带有这样一个参数 var endDate = new Date(""); // today var startDate = new Date() startDate.setDate(startDate.getDate() - 5); var request = "http://ichart.finance.yahoo.com/table.csv?"; request += "s=" + stockId; request += "&g=d"; request += "&a=" + startDate.getMonth(); request += "&b=" + startDate.getDate(); request += "&c=" + startDate.getFullYear(); request += "&d=" + endDate.getMonth(); request += "&e=" + endDate.getDate(); request += "&f=" + endDate.getFullYear(); request += "&g=d"; request += "&ignore=.csv"; return request; } function getCloseValue(index) { var req = requestUrl(model.get(index).stockId); // 得到对应的股票Id if (!req) return; 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'); if (records.length > 0) { var r = records[1].split(','); // 第一条数据,即最新一天的数据 model.setProperty(index, "value", r[4]); // 与StockModel类似,第五个数据为'Close',即收盘价 // 这里将model中index位置数据的"value"值设置为该收盘价 // 注意这个model是StockListModel而不是StockModel var today = parseFloat(r[4]); // parseFloat()将字符串转化成浮点数,变量声明为var而不是real r = records[2].split(','); // 再取前一天数据 var yesterday = parseFloat(r[4]); var change = today - yesterday; // 计算变化值 if (change >= 0.0) model.setProperty(index, "change", "+" + change.toFixed(2)); // 同样对model赋值大于零则带+号,保留两位小数 else model.setProperty(index, "change", change.toFixed(2)); var changePercentage = (change / yesterday) * 100.0; // 变化率百分比 if (changePercentage >= 0.0) model.setProperty(index, "changePercentage", "+" + changePercentage.toFixed(2) + "%"); else model.setProperty(index, "changePercentage", changePercentage.toFixed(2) + "%"); } } } xhr.send() // 发送请求 } onCurrentIndexChanged: { // 当该ListView中的某个项目被选中 mainRect.listViewActive = 0; // 切换主ListView的页面 root.currentStockId = model.get(currentIndex).stockId; // 获取 Id 与 name root.currentStockName = model.get(currentIndex).name; } delegate: Rectangle { // 委托组件,基本都是布局,不多说了 height: 102 width: parent.width color: "transparent" MouseArea { anchors.fill: parent; onClicked: { view.currentIndex = index; } } Text { id: stockIdText anchors.top: parent.top anchors.topMargin: 15 anchors.left: parent.left anchors.leftMargin: 15 width: 125 height: 40 color: "#000000" font.family: "Open Sans" // 我的机器貌似不支持这种字体 font.pointSize: 20 font.weight: Font.Bold verticalAlignment: Text.AlignVCenter text: stockId } Text { id: stockValueText anchors.top: parent.top anchors.topMargin: 15 anchors.right: parent.right anchors.rightMargin: 0.31 * parent.width width: 190 height: 40 color: "#000000" font.family: "Open Sans" font.pointSize: 20 font.bold: true horizontalAlignment: Text.AlignRight verticalAlignment: Text.AlignVCenter text: value Component.onCompleted: view.getCloseValue(index); } Text { id: stockValueChangeText anchors.top: parent.top anchors.topMargin: 15 anchors.right: parent.right anchors.rightMargin: 20 width: 135 height: 40 color: "#328930" font.family: "Open Sans" font.pointSize: 20 font.bold: true horizontalAlignment: Text.AlignRight verticalAlignment: Text.AlignVCenter text: change onTextChanged: { if (parseFloat(text) >= 0.0) // 正为绿色,负为红色 color = "#328930"; else color = "#d40000"; } } Text { id: stockNameText anchors.top: stockIdText.bottom anchors.left: parent.left anchors.leftMargin: 15 width: 330 height: 30 color: "#000000" font.family: "Open Sans" font.pointSize: 16 font.bold: false elide: Text.ElideRight maximumLineCount: 1 verticalAlignment: Text.AlignVCenter text: name } Text { id: stockValueChangePercentageText anchors.top: stockIdText.bottom anchors.right: parent.right anchors.rightMargin: 20 width: 120 height: 30 color: "#328930" font.family: "Open Sans" font.pointSize: 18 font.bold: false horizontalAlignment: Text.AlignRight verticalAlignment: Text.AlignVCenter text: changePercentage onTextChanged: { if (parseFloat(text) >= 0.0) color = "#328930"; else color = "#d40000"; } } Rectangle { id: endingLine anchors.bottom: parent.bottom anchors.left: parent.left height: 1 width: parent.width color: "#d7d7d7" } } highlight: Rectangle { width: parent.width color: "#eeeeee" } } }
为了支撑这个StockListView,我们还需要一个StockListModel.qml:
它同样是一个ListModel,由许多个ListElement构成,代码也很明了。除了name和stockId 被赋值外,value,change,changePercentage都是在view中被动态赋值的,因此均初始化为0.0。
import QtQuick 2.0 ListModel { id: stocks // Data from : http://en.wikipedia.org/wiki/NASDAQ-100 // 这里告诉了我们数据来源 ListElement {name: "Apple Inc."; stockId: "AAPL"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Adobe Systems Inc."; stockId: "ADBE"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Analog Devices, Inc."; stockId: "ADI"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Automatic Data Processing, Inc."; stockId: "ADP"; 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: "Akamai Technologies, Inc."; stockId: "AKAM"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Altera Corp."; stockId: "ALTR"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Alexion Pharmaceuticals, Inc."; stockId: "ALXN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Applied Materials, Inc."; stockId: "AMAT"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Amgen Inc."; stockId: "AMGN"; 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: "Activision Blizzard, Inc."; stockId: "ATVI"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Avago Technologies Limited"; stockId: "AVGO"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Bed Bath & Beyond Inc."; stockId: "BBBY"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Baidu, Inc."; stockId: "BIDU"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Biogen Idec Inc."; stockId: "BIIB"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Broadcom Corp."; stockId: "BRCM"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "CA Technologies"; stockId: "CA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Celgene Corporation"; stockId: "CELG"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Cerner Corporation"; stockId: "CERN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Check Point Software Technologies Ltd."; stockId: "CHKP"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "CH Robinson Worldwide Inc."; stockId: "CHRW"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Charter Communications, Inc."; stockId: "CHTR"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Comcast Corporation"; stockId: "CMCSA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Costco Wholesale Corporation"; stockId: "COST"; 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: "Catamaran Corporation"; stockId: "CTRX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Cognizant Technology Solutions Corporation"; stockId: "CTSH"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Citrix Systems, Inc."; stockId: "CTXS"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Discovery Communications, Inc."; stockId: "DISCA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Dish Network Corp."; stockId: "DISH"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Dollar Tree, Inc."; stockId: "DLTR"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "DIRECTV"; stockId: "DTV"; 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: "Equinix, Inc."; stockId: "EQIX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Express Scripts Holding Company"; stockId: "ESRX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Expeditors International of Washington Inc."; stockId: "EXPD"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Expedia Inc."; stockId: "EXPE"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Fastenal Company"; stockId: "FAST"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Facebook, Inc."; stockId: "FB"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "F5 Networks, Inc."; stockId: "FFIV"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Fiserv, Inc."; stockId: "FISV"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Twenty-First Century Fox, Inc."; stockId: "FOXA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Gilead Sciences Inc."; stockId: "GILD"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Keurig Green Mountain, Inc."; stockId: "GMCR"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Google Inc."; stockId: "GOOG"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Google Inc."; stockId: "GOOGL"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Garmin Ltd."; stockId: "GRMN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Henry Schein, Inc."; stockId: "HSIC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Illumina Inc."; stockId: "ILMN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Intel Corporation"; stockId: "INTC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Intuit Inc."; stockId: "INTU"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Intuitive Surgical, Inc."; stockId: "ISRG"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "KLA-Tencor Corporation"; stockId: "KLAC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Kraft Foods Group, Inc."; stockId: "KRFT"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Liberty Global plc"; stockId: "LBTYA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Liberty Interactive Corporation"; stockId: "LINTA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Linear Technology Corporation"; stockId: "LLTC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Liberty Media Corporation"; stockId: "LMCA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Marriott International, Inc."; stockId: "MAR"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Mattel, Inc"; stockId: "MAT"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Mondelez International, Inc."; stockId: "MDLZ"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Monster Beverage Corporation"; stockId: "MNST"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Microsoft Corporation"; stockId: "MSFT"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Micron Technology Inc."; stockId: "MU"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Maxim Integrated Products, Inc."; stockId: "MXIM"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Mylan, Inc."; stockId: "MYL"; 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: "NetApp, Inc."; stockId: "NTAP"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "NVIDIA Corporation"; stockId: "NVDA"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "NXP Semiconductors NV"; stockId: "NXPI"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "O'Reilly Automotive Inc."; stockId: "ORLY"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Paychex, Inc."; stockId: "PAYX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "PACCAR Inc."; stockId: "PCAR"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "The Priceline Group Inc."; stockId: "PCLN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "QUALCOMM Incorporated"; stockId: "QCOM"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Regeneron Pharmaceuticals, Inc."; stockId: "REGN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Ross Stores Inc."; stockId: "ROST"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "SBA Communications Corp."; stockId: "SBAC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Starbucks Corporation"; stockId: "SBUX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Sigma-Aldrich Corporation"; stockId: "SIAL"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Sirius XM Holdings Inc."; stockId: "SIRI"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "SanDisk Corp."; stockId: "SNDK"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Staples, Inc."; stockId: "SPLS"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Stericycle, Inc."; stockId: "SRCL"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Seagate Technology Public Limited Company"; stockId: "STX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Symantec Corporation"; stockId: "SYMC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "TripAdvisor Inc."; stockId: "TRIP"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Tractor Supply Company"; stockId: "TSCO"; 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: "Viacom, Inc."; stockId: "VIAB"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "VimpelCom Ltd."; stockId: "VIP"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Vodafone Group Public Limited Company"; stockId: "VOD"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Verisk Analytics, Inc."; stockId: "VRSK"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Vertex Pharmaceuticals Incorporated"; stockId: "VRTX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Western Digital Corporation"; stockId: "WDC"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Whole Foods Market, Inc."; stockId: "WFM"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Wynn Resorts Ltd."; stockId: "WYNN"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} ListElement {name: "Xilinx Inc."; stockId: "XLNX"; value: "0.0"; change: "0.0"; changePercentage: "0.0"} }
骨架已成,我们接下来就要为它添加血肉了。我在网上看到有人认为底层先于界面开发更快,也有人认为先搭界面框架再做底层更好。嗯...我倒觉得谈不上好坏之分,关键在于动手之前得有一个清晰的架构。不过底层在设计之初能够拥有丰富的API 减少日后改动,界面最初设计不要要求太高(因为总是会改的。。。),这样应该会让人比较舒服一些~
好了,扯远了,下面的StockView即是我们一开始看到的曲线界面,看看它包含哪些东西:
import QtQuick 2.0 import QtQuick.Window 2.1 // 下面的代码使用了Screen因此引入这个模块 Rectangle { id: root width: 320 height: 480 color: "transparent" property var stock: null property var stocklist: null signal settingsClicked function update() { // 用来更新图表显示 chart.update() } Rectangle { id: mainRect color: "transparent" anchors.fill: parent StockInfo { // 提供左上方的股票信息 id: stockInfo anchors.left: parent.left anchors.leftMargin: 10 anchors.top: parent.top anchors.topMargin: 15 height: 160 anchors.right: Screen.primaryOrientation === Qt.PortraitOrientation ? parent.right : chart.left // 基于属性绑定的屏幕转向后布局方式的变化 anchors.rightMargin: 20 stock: root.stock } StockChart { // 右方的曲线绘制部分 id: chart anchors.bottom: Screen.primaryOrientation === Qt.PortraitOrientation ? settingsPanel.top : parent.bottom anchors.bottomMargin: 20 anchors.top : Screen.primaryOrientation === Qt.PortraitOrientation ? stockInfo.bottom : parent.top anchors.topMargin: 20 anchors.right: parent.right anchors.rightMargin: 20 width: Screen.primaryOrientation === Qt.PortraitOrientation ? parent.width - 40 : 0.6 * parent.width stockModel: root.stock settings: settingsPanel } StockSettingsPanel { // 左下方的显示设置面板 id: settingsPanel anchors.left: parent.left anchors.leftMargin: 20 anchors.right: Screen.primaryOrientation === Qt.PortraitOrientation ? parent.right : chart.left anchors.rightMargin: 20 anchors.bottom: parent.bottom onDrawOpenPriceChanged: root.update() // 更新 onDrawClosePriceChanged: root.update(); onDrawHighPriceChanged: root.update(); onDrawLowPriceChanged: root.update(); } } }
可以看到StockView由3个主要部分构成,分别是显示当前股票信息的StockInfo、设置显示曲线的StockSettingPanel、以及最后的绘图部分StockChart。
我们按顺序来看,StockInfo.qml:
import QtQuick 2.0 Rectangle { // 根项目是一个透明的Rectangle。为什么不用Item,我想可能是因为当时布局的时候把color设置出来可能更方便一些 id: root width: 440 height: 160 color: "transparent" property var stock: null // var类型的stock属性,它接受的是stocqt.qml中定义的StockModel Text { // id id: stockIdText anchors.left: parent.left anchors.leftMargin: 5 anchors.top: parent.top anchors.topMargin: 15 color: "#000000" font.family: "Open Sans" font.pointSize: 38 font.weight: Font.DemiBold text: root.stock.stockId // 类似的,对显示文本赋值 } Text { // name id: stockNameText anchors.left: parent.left anchors.leftMargin: 5 anchors.bottom: priceChangePercentage.bottom anchors.right: priceChangePercentage.left anchors.rightMargin: 15 color: "#000000" font.family: "Open Sans" font.pointSize: 16 elide: Text.ElideRight text: root.stock.stockName } Text { // 价格 id: price anchors.right: parent.right anchors.rightMargin: 5 anchors.top: parent.top anchors.topMargin: 15 horizontalAlignment: Text.AlignRight color: "#000000" font.family: "Open Sans" font.pointSize: 30 font.weight: Font.DemiBold text: root.stock.stockPrice } Text { // 价格变化 id: priceChange anchors.right: parent.right anchors.rightMargin: 20 anchors.top: price.bottom anchors.topMargin: 5 horizontalAlignment: Text.AlignRight color: root.stock.stockPriceChanged < 0 ? "#d40000" : "#328930" font.family: "Open Sans" font.pointSize: 20 font.weight: Font.Bold text: root.stock.stockPriceChanged } Text { // 价格变化百分比 id: priceChangePercentage anchors.right: parent.right anchors.rightMargin: 20 anchors.top: priceChange.bottom anchors.topMargin: 5 horizontalAlignment: Text.AlignRight color: root.stock.stockPriceChanged < 0 ? "#d40000" : "#328930" font.family: "Open Sans" font.pointSize: 18 font.weight: Font.Bold text: Math.abs(Math.round(root.stock.stockPriceChanged/(root.stock.stockPrice - root.stock.stockPriceChanged) * 100))/100 +"%" } }
stockSettingPanel.qml:
import QtQuick 2.0 Rectangle { id: root width: 440 height: 160 color: "transparent" property bool drawOpenPrice: openButton.buttonEnabled // 对外的标志位 property bool drawClosePrice: closeButton.buttonEnabled property bool drawHighPrice: highButton.buttonEnabled property bool drawLowPrice: lowButton.buttonEnabled property string openColor: "#face20" // 各曲线的颜色设置 property string closeColor: "#14aaff" property string highColor: "#80c342" property string lowColor: "#f30000" property string volumeColor: "#14aaff" // 股票颜色 Text { id: openText anchors.left: root.left anchors.top: root.top color: "#000000" font.family: "Open Sans" font.pointSize: 19 text: "Open" } Text { id: closeText anchors.left: root.left anchors.top: openText.bottom anchors.topMargin: 10 color: "#000000" font.family: "Open Sans" font.pointSize: 19 text: "Close" } Text { id: highText anchors.left: root.left anchors.top: closeText.bottom anchors.topMargin: 10 color: "#000000" font.family: "Open Sans" font.pointSize: 19 text: "High" } Text { id: lowText anchors.left: root.left anchors.top: highText.bottom anchors.topMargin: 10 color: "#000000" font.family: "Open Sans" font.pointSize: 19 text: "Low" } Rectangle { height: 4 anchors.left: root.left anchors.leftMargin: 114 anchors.right: openButton.left anchors.rightMargin: 65 anchors.verticalCenter: openText.verticalCenter color: openColor } Rectangle { height: 4 anchors.left: root.left anchors.leftMargin: 114 anchors.right: closeButton.left anchors.rightMargin: 65 anchors.verticalCenter: closeText.verticalCenter color: closeColor } Rectangle { height: 4 anchors.left: root.left anchors.leftMargin: 114 anchors.right: highButton.left anchors.rightMargin: 65 anchors.verticalCenter: highText.verticalCenter color: highColor } Rectangle { height: 4 anchors.left: root.left anchors.leftMargin: 114 anchors.right: lowButton.left anchors.rightMargin: 65 anchors.verticalCenter: lowText.verticalCenter color: lowColor } CheckBox { // 自定义的CheckBox,提供了属性buttonEnabled表明是否被checked id: openButton buttonEnabled: false anchors.verticalCenter: openText.verticalCenter anchors.right: root.right anchors.rightMargin: 40 } CheckBox { id: closeButton buttonEnabled: false anchors.verticalCenter: closeText.verticalCenter anchors.right: root.right anchors.rightMargin: 40 } CheckBox { id: highButton buttonEnabled: true anchors.verticalCenter: highText.verticalCenter anchors.right: root.right anchors.rightMargin: 40 } CheckBox { id: lowButton buttonEnabled: true anchors.verticalCenter: lowText.verticalCenter anchors.right: root.right anchors.rightMargin: 40 } }
自定义的CheckBox.qml:
import QtQuick 2.0 Item { id: button property bool buttonEnabled: true width: 30 height: 30 x: 5 MouseArea { id: mouse anchors.fill: parent onClicked: { if (buttonEnabled) buttonEnabled = false; else buttonEnabled = true; } } Rectangle { id: checkbox width: 30 height: 30 anchors.left: parent.left border.color: "#999999" border.width: 1 antialiasing: true radius: 2 color: "transparent" Rectangle { anchors.fill: parent anchors.margins: 5 antialiasing: true radius: 1 color: mouse.pressed || buttonEnabled ? "#999999" : "transparent" } } }
接着还有一个自定义的控件Button.qml,它在下面的StockChart将会用到:
import QtQuick 2.0 Rectangle { id: button signal clicked property alias text: txt.text // 设置txt.text的属性别名为text,这样Rectangle就不用再声明一个属性以访问txt的text property bool buttonEnabled: false width: Math.max(64, txt.width + 16) height: 32 color: "transparent" MouseArea { anchors.fill: parent onClicked: button.clicked() } Text { anchors.centerIn: parent font.family: "Open Sans" font.pointSize: 19 font.weight: Font.DemiBold color: button.buttonEnabled ? "#000000" : "#14aaff" id: txt } }
最终的绘制部分终于来了,StockChart.qml:
import QtQuick 2.0 Rectangle { id: chart width: 320 height: 200 property var stockModel: null property var startDate: new Date() // new Date()初始化得到的是当前时间 property var endDate: new Date() property string activeChart: "year" // 设置表格显示的时间跨度为一年 property var settings property int gridSize: 4 // 每个网格宽度为4px property real gridStep: gridSize ? (width - canvas.tickMargin) / gridSize : canvas.xGridStep // 网格数为(宽度 - 最右方那一栏的宽度)/ 网格宽度,如果gridSize为0,采用画布中的计算方式 function update() { // 更新函数 endDate = new Date(); if (chart.activeChart === "year") { // 显示一年数据 chart.startDate = new Date(chart.endDate.getFullYear() - 1, // 在当前时间的基础上减一年 chart.endDate.getMonth(), chart.endDate.getDate()); chart.gridSize = 12; // 设置网格宽度为12,以固定网格数 } else if (chart.activeChart === "month") { // 显示一个月数据 chart.startDate = new Date(chart.endDate.getFullYear(), // 在当前时间基础上减一个月 chart.endDate.getMonth() - 1, chart.endDate.getDate()); gridSize = 0; // gridSize为0时,采用canvas中定义的网格宽度计算。使每个数据都绘制在坐标线上 } else if (chart.activeChart === "week") { // 显示一周数据 chart.startDate = new Date(chart.endDate.getFullYear(), // 在当前时间基础上减七天 chart.endDate.getMonth(), chart.endDate.getDate() - 7); gridSize = 0; } else { chart.startDate = new Date(2005, 3, 25); // 否则以2005年为初始年,并定义网格宽度为4 gridSize = 4; } canvas.requestPaint(); // 当更新时需要调用画布的这个函数 } Row { // Row布局了4个自定义的按钮 id: activeChartRow anchors.left: chart.left anchors.right: chart.right anchors.top: chart.top anchors.topMargin: 4 spacing: 52 onWidthChanged: { // 该函数保证宽度变化时优先压缩spacing,且不会造成按钮重叠 var buttonsLen = maxButton.width + yearButton.width + monthButton.width + weekButton.width; var space = (width - buttonsLen) / 3; spacing = Math.max(space, 10); } Button { id: maxButton text: "Max" buttonEnabled: chart.activeChart === "max" onClicked: { chart.activeChart = "max"; // 改变当前图表显示模式,这里的max 实际对应update中的'else',即2005年作为起始年 chart.update(); // 更新 } } Button { id: yearButton text: "Year" buttonEnabled: chart.activeChart === "year" onClicked: { chart.activeChart = "year"; chart.update(); } } Button { id: monthButton text: "Month" buttonEnabled: chart.activeChart === "month" onClicked: { chart.activeChart = "month"; chart.update(); } } Button { id: weekButton text: "Week" buttonEnabled: chart.activeChart === "week" onClicked: { chart.activeChart = "week"; chart.update(); } } } Text { // 下方的起始日期显示 id: fromDate color: "#000000" font.family: "Open Sans" font.pointSize: 8 anchors.left: parent.left anchors.bottom: parent.bottom text: "| " + startDate.toDateString() } Text { // 结束日期显示 id: toDate color: "#000000" font.family: "Open Sans" font.pointSize: 8 anchors.right: parent.right anchors.rightMargin: canvas.tickMargin anchors.bottom: parent.bottom text: endDate.toDateString() + " |" } Canvas { // 画布,基本上与HTML的Canvas相同 id: canvas // 注释介绍将下面两行语句取消注释以获得OpenGL的硬件加速渲染,为什么没有开?有些平台不支持嘛... // Uncomment below lines to use OpenGL hardware accelerated rendering. // See Canvas documentation for available options. //renderTarget: Canvas.FramebufferObject // 渲染到OpenGL的帧缓冲 //renderStrategy: Canvas.Threaded // 渲染工作在一个私有渲染线程中进行 anchors.top: activeChartRow.bottom // 作为Item的派生类型,我们同样可以设置它的布局与属性 anchors.left: parent.left anchors.right: parent.right anchors.bottom: fromDate.top property int pixelSkip: 1 property int numPoints: 1 // 存储数据点的个数 property int tickMargin: 32 // 右边格的宽度 property real xGridStep: (width - tickMargin) / numPoints // 网格宽度 property real yGridOffset: height / 26 // y方向向下的偏移度,用在水平线的绘制 property real yGridStep: height / 12 // 网格高度 function drawBackground(ctx) { // 界面的绘制由onPaint开始,这是绘制背景的一个函数。ctx作为传参,类似C++中的painter ctx.save(); // 保存之前绘制内容 ctx.fillStyle = "#ffffff"; // 填充颜色,之所以叫Style是因为它还可以使用渐变等等... ctx.fillRect(0, 0, canvas.width, canvas.height); // fillRect是一个便利函数,用来填充一个矩形区域 ctx.strokeStyle = "#d7d7d7"; // 描边颜色 ctx.beginPath(); // 水平网格线 for (var i = 0; i < 12; i++) { ctx.moveTo(0, canvas.yGridOffset + i * canvas.yGridStep); ctx.lineTo(canvas.width, canvas.yGridOffset + i * canvas.yGridStep); } // 垂直网格线 var height = 35 * canvas.height / 36; // 垂直线的高度为画布高度的 35/36 var yOffset = canvas.height - height; // 垂直线离顶部距离为高度的 1/36 var xOffset = 0; for (i = 0; i < chart.gridSize; i++) { ctx.moveTo(xOffset + i * chart.gridStep, yOffset); ctx.lineTo(xOffset + i * chart.gridStep, height); } ctx.stroke(); // 描线 // 右方以及下方颜色较深的那几根线 ctx.strokeStyle = "#666666"; ctx.beginPath(); var xStart = canvas.width - tickMargin; // x = 画布宽度 - 价格部分宽度 ctx.moveTo(xStart, 0); ctx.lineTo(xStart, canvas.height); // 向下画直线 for (i = 0; i < 12; i++) { ctx.moveTo(xStart, canvas.yGridOffset + i * canvas.yGridStep); // 12根短横线 ctx.lineTo(canvas.width, canvas.yGridOffset + i * canvas.yGridStep); } ctx.moveTo(0, canvas.yGridOffset + 9 * canvas.yGridStep); // 移动绘制点到第九根横线左端 ctx.lineTo(canvas.width, canvas.yGridOffset + 9 * canvas.yGridStep); // 向右绘制横线 ctx.closePath(); // 完成路径 ctx.stroke(); // 描边 ctx.restore(); // 载入保存的内容 } function drawScales(ctx, high, low, vol) // 绘制右方股票价格标尺函数 { ctx.save(); ctx.strokeStyle = "#888888"; ctx.font = "10px Open Sans" ctx.beginPath(); // prices on y-axis var x = canvas.width - tickMargin + 3; // 离右边实线3px var priceStep = (high - low) / 9.0; // 相隔最高价与最低价的差值除以9 for (var i = 0; i < 10; i += 2) { // 隔一级显示 var price = parseFloat(high - i * priceStep).toFixed(1); ctx.text(price, x, canvas.yGridOffset + i * yGridStep - 2); // 绘制text的坐标在文字的左下角 } // highest volume ctx.text(vol, 0, canvas.yGridOffset + 9 * yGridStep + 12); // 绘制最高成交量 ctx.closePath(); ctx.stroke(); ctx.restore(); } function drawPrice(ctx, from, to, color, price, points, highest, lowest) // 数据曲线绘制 { ctx.save(); ctx.globalAlpha = 0.7; // 透明度 ctx.strokeStyle = color; // color由StockSettingPanel指定 ctx.lineWidth = 3; ctx.beginPath(); var end = points.length; // 数据长度 var range = highest - lowest; // 取值范围 if (range == 0) { range = 1; // range作为被除数不能为0 } for (var i = 0; i < end; i += pixelSkip) { var x = points[i].x; var y = points[i][price]; // 取出对应设置的价格数据 var h = 9 * yGridStep; // 设置绘制高度为九倍的网格高度 y = h * (lowest - y)/range + h + yGridOffset; // lowest - y为非正数,h + yGridOffset为曲线绘制的底部 if (i == 0) { ctx.moveTo(x, y); // 移动到初始点 } else { ctx.lineTo(x, y); // 向后绘制 } } ctx.stroke(); ctx.restore(); } function drawVolume(ctx, from, to, color, price, points, highest) // 成交量绘制函数 { ctx.save(); ctx.fillStyle = color; ctx.globalAlpha = 0.8; ctx.lineWidth = 0; // 由于线宽影响绘制边界(参考HTML),这里将线宽设置为0 ctx.beginPath(); var end = points.length; var margin = 0; if (chart.activeChart === "month" || chart.activeChart === "week") { margin = 8; ctx.shadowOffsetX = 4; // x方向的阴影 ctx.shadowBlur = 3.5; // 模糊效果 ctx.shadowColor = Qt.darker(color); } // 由于柱状图的宽度限制,柱状图比实际的数据少一个 // To match the volume graph with price grid, skip drawing the initial // volume of the first day on chart. for (var i = 1; i < end; i += pixelSkip) { var x = points[i - 1].x; var y = points[i][price]; y = canvas.height * (y / highest); y = 3 * y / 12; // 柱状图高度占画布的1/4 ctx.fillRect(x, canvas.height - y + yGridOffset, canvas.xGridStep - margin, y); // "周"与"月"时有间隔,其他则没有 } ctx.stroke(); ctx.restore(); } onPaint: { // 绘制入口 if (!stockModel.ready) { // 等待数据完成 return; } numPoints = stockModel.indexOf(chart.startDate); // 由StockModel取得startDate到现在的数据数 if (chart.gridSize == 0) chart.gridSize = numPoints // 使gridStep绑定到(width - canvas.tickMargin) / numPoints上 var ctx = canvas.getContext("2d"); // 创建ctx ctx.globalCompositeOperation = "source-over"; // 混合模式 ctx.lineWidth = 1; drawBackground(ctx); // 背景绘制 var highestPrice = 0; var highestVolume = 0; var lowestPrice = -1; var points = []; // 创建一个数组 for (var i = numPoints, j = 0; i >= 0 ; i -= pixelSkip, j += pixelSkip) { // pixelSkip被定义为 1 var price = stockModel.get(i); if (parseFloat(highestPrice) < parseFloat(price.high)) // 得到最高价 highestPrice = price.high; if (parseInt(highestVolume, 10) < parseInt(price.volume, 10)) // 得到最低价 highestVolume = price.volume; if (lowestPrice < 0 || parseFloat(lowestPrice) > parseFloat(price.low)) // 注意这里如果设置lowestPrice = 0或是别的数 lowestPrice = price.low; // 就有可能一直无法满足条件,因此添加这个负数使第一个price.low被赋予lowestPrice points.push({ // 插入数据,它类似于Model,但多了一个 x 的坐标值 x: j * xGridStep, open: price.open, close: price.close, high: price.high, low: price.low, volume: price.volume }); } if (settings.drawHighPrice) // 判断StockSettingPanel中相应的选项是否被勾选,然后绘制数据线段 drawPrice(ctx, 0, numPoints, settings.highColor, "high", points, highestPrice, lowestPrice); if (settings.drawLowPrice) drawPrice(ctx, 0, numPoints, settings.lowColor, "low", points, highestPrice, lowestPrice); if (settings.drawOpenPrice) drawPrice(ctx, 0, numPoints,settings.openColor, "open", points, highestPrice, lowestPrice); if (settings.drawClosePrice) drawPrice(ctx, 0, numPoints, settings.closeColor, "close", points, highestPrice, lowestPrice); drawVolume(ctx, 0, numPoints, settings.volumeColor, "volume", points, highestVolume); // 成交量绘制 drawScales(ctx, highestPrice, lowestPrice, highestVolume); // 价格标尺绘制 } } }