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                本系列所有文章可以在這里查看[http://blog.csdn.net/cloud_castle/article/category/2123873](http://blog.csdn.net/cloud_castle/article/category/2123873) 接上文[Qt5官方demo解析集30——Extending QML - Binding Example](http://blog.csdn.net/cloud_castle/article/details/37534507) 最近在做QML制表,因此想找一些相關曲線繪制的demo看看,結果發現了這個例子,覺得挺不錯,它相比于我們之前的Extend和Particle系列顯得更大一些,涉及到的面也更廣一些。因此想拿過來給大家分享~ 這個例子是基于QML的股票走勢圖繪制,數據來源于yahoo的納達克斯-100指數,向左滑動可以選擇股票。 曲線頁面: ![](https://box.kancloud.cn/2016-01-18_569cbd092e045.jpg) 列表頁面: ![](https://box.kancloud.cn/2016-01-18_569cbd094a46e.jpg) 工程目錄如下: ![](https://box.kancloud.cn/2016-01-18_569cbd09612bf.jpg) 這個例子的結構會稍微復雜一些,我建議大家在QtCreator中將這個例子打開,這樣有什么想法或是疑慮時我們可以將代碼改改,或是添加一些輸出信息,舉一反三的學習總是比較有效的。 ok,我們自頂而下的跟著調用的順序來: stocqt.qml: ~~~ import QtQuick 2.0 import QtQml.Models 2.1 import "./content" // 添加其他qml文件路徑 Rectangle { id: mainRect width: 1000 height: 700 property int listViewActive: 0 // 該頁面實際是一個ListView的一部分,這個屬性用來表明前面的列表頁面是否被激活 Rectangle { // 導航欄 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 // 曲線頁面是ListView的第二個頁面,currentIndex的值也就是1 MouseArea { anchors.fill: parent onClicked: listViewActive = 1; } } Item { // 將相關組件放在一個Item容器中 id: textItem width: stocText.width + qtText.width // 容器的尺寸由組件決定 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 { // 標題欄下方則是ListView的內容,它為列表頁面與曲線頁面提供了滑動切換的能力 id: root width: parent.width anchors.top: banner.bottom anchors.bottom: parent.bottom snapMode: ListView.SnapOneItem // 設置該屬性使View停止在一個完整的頁面上 highlightRangeMode: ListView.StrictlyEnforceRange highlightMoveDuration: 250 // 這里設置了一個無形的高亮,它不顯示,但提供了0.25秒的切換動畫 focus: false orientation: ListView.Horizontal boundsBehavior: Flickable.StopAtBounds // 滑動時停在邊界,默認可以拉拽更遠并在彈回時帶有超調效果 currentIndex: listViewActive == 0 ? 1 : 0 // 使用屬性綁定,當listViewActive被激活時,使currentIndex置0,從而跳轉到列表頁面 onCurrentIndexChanged: { if (currentIndex == 1) listViewActive = 0; } StockModel { // 初始化數據模型 id: stock stockId: listView.currentStockId // 注意這個listView不是其父ListView,而是下面那個,即列表頁面 stockName: listView.currentStockName // 列表頁面將當前所選的股票ID及名字賦給StockModel,使其取得相應的數據 onStockIdChanged: stock.updateStock(); // 當ID改變時數據更新 onDataReady: { console.log(listView.currentStockId, listView.currentStockName) root.positionViewAtIndex(1, ListView.SnapPosition) // 上面的高亮即為這里的ListView.SnapPosition做準備,數據變更后切換到曲線頁面,帶有0.25秒的過渡動畫 stockView.update() // 頁面更新 } } model: ObjectModel { // ObjectModel源自上面import的Qt.QML.Model 2.1,它使得ListView可以使用一組對象作為模型 StockListView { // 列表頁面 id: listView width: root.width height: root.height } StockView { // 曲線頁面 id: stockView width: root.width height: root.height stocklist: listView stock: stock } } } } ~~~ 有人說數據是一個程序骨架,那就看看這個架子吧~ StockModel.qml: ~~~ import QtQuick 2.0 ListModel { // ListModel作為根項目,自定義屬性作為接口,并定義了多個函數。但他本身在初始化時并不進行運算 id: model property string stockId: "" // 股票ID property string stockName: "" // 股票名 property string stockDataCycle: "d" // 數據周期 property bool ready: false // 標志位 property real stockPrice: 0.0 // 股票價格 property real stockPriceChanged: 0.0 // 價格變化 signal dataReady // 耗時的數據類通常需要定義這個信號 function indexOf(date) { // 返回從特定date的數據在數據集中的位置 var newest = new Date(model.get(0).date); // 獲取第一個數據對象的日期 var oldest = new Date(model.get(model.count - 1).date); // 最后一個數據對象的日期 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; // 返回變量 for (var i = 0; i < model.count; i++) { var d = new Date(model.get(i).date); currDiff = Math.abs(d.getTime() - date.getTime()); // 計算時間差值 if (currDiff < bestDiff) { // 從最新時間向目標時間推進 bestDiff = currDiff; retval = i; // retval記錄數據位置 } if (currDiff > bestDiff) // 當達到目標時間后 return retval; // 將數據位置返回 } return -1; } function requestUrl() { // 創建請求數據的url字符串函數 if (stockId === "") return; var startDate = new Date(2011, 4, 25); // 指定一個開始時間 var endDate = new Date(); // 結束時間為當前時間 if (stockDataCycle !== "d" && stockDataCycle !== "w" && stockDataCycle !== "m") stockDataCycle = "d"; // 如果數據周期不是'天'、'周'、'月',則定義為'天' /* // 注釋給出了向yahoo請求數據的格式 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; // 返回這一長串url } function createStockPrice(r) { // 存儲數據對象函數 return { // 用來接收下面分離的7位數據,以類似結構體的形式存儲下來 "date": r[0], // 這也是該model真正存儲的數據類型格式 "open":r[1], "high":r[2], "low":r[3], "close":r[4], "volume":r[5], "adjusted":r[6] }; } function updateStock() { // 數據更新 var req = requestUrl(); // 得到請求數據的url字符串 if (!req) return; var xhr = new XMLHttpRequest; // 創建一個XMLHttp的請求對象 xhr.open("GET", req, true); // 初始化請求參數,還未發送請求 model.ready = false; // 標志位置false model.clear(); // 數據清空 var i = 1; // 輸出一下調試信息可知,返回的數據第一行為描述符,因此將其跳過 xhr.onreadystatechange = function() { // readyState是XMLHttpRequest的一個屬性,其值從0變化到4 if (xhr.readyState === XMLHttpRequest.LOADING || xhr.readyState === XMLHttpRequest.DONE) { var records = xhr.responseText.split('\n'); // LOADING為3,DONE為4,分別表示數據正在載入和載入完成 // 以換行符分割數據 for (;i < records.length; i++ ) { var r = records[i].split(','); // 以逗號將數據分割 if (r.length === 7) // 數據校驗 model.append(createStockPrice(r)); // 函數調用,向model中添加數據 } if (xhr.readyState === XMLHttpRequest.DONE) { if (model.count > 0) { model.ready = true; model.stockPrice = model.get(0).adjusted; // 將最新的的調整收盤價賦予stockPrice model.stockPriceChanged = model.count > 1 ? (Math.round((model.stockPrice - model.get(1).close) * 100) / 100) : 0; // 相比前一天的收盤價變化率 model.dataReady(); //emit signal } } } } xhr.send() // 實際發出數據請求 } } ~~~ 我們將records的數據部分貼出來: ![](https://box.kancloud.cn/2016-01-18_569cbd096d1a2.jpg) 實際的數據被'\n'分開,也就是說,類似下面這個樣子: 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......) 為了得到各股的變化率等,StockListView也采取了類似的實現方式: 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以延時加載數據 keyNavigationWraps: true highlightMoveDuration: 0 focus: true snapMode: ListView.SnapToItem model: StockListModel{} // 定義model function requestUrl(stockId) { // 最近5天的url創建函數,與StockModel不同的是,由于未定義stockId屬性,它帶有這樣一個參數 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); // 得到對應的股票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(','); // 第一條數據,即最新一天的數據 model.setProperty(index, "value", r[4]); // 與StockModel類似,第五個數據為'Close',即收盤價 // 這里將model中index位置數據的"value"值設置為該收盤價 // 注意這個model是StockListModel而不是StockModel var today = parseFloat(r[4]); // parseFloat()將字符串轉化成浮點數,變量聲明為var而不是real r = records[2].split(','); // 再取前一天數據 var yesterday = parseFloat(r[4]); var change = today - yesterday; // 計算變化值 if (change >= 0.0) model.setProperty(index, "change", "+" + change.toFixed(2)); // 同樣對model賦值大于零則帶+號,保留兩位小數 else model.setProperty(index, "change", change.toFixed(2)); var changePercentage = (change / yesterday) * 100.0; // 變化率百分比 if (changePercentage >= 0.0) model.setProperty(index, "changePercentage", "+" + changePercentage.toFixed(2) + "%"); else model.setProperty(index, "changePercentage", changePercentage.toFixed(2) + "%"); } } } xhr.send() // 發送請求 } onCurrentIndexChanged: { // 當該ListView中的某個項目被選中 mainRect.listViewActive = 0; // 切換主ListView的頁面 root.currentStockId = model.get(currentIndex).stockId; // 獲取 Id 與 name root.currentStockName = model.get(currentIndex).name; } delegate: Rectangle { // 委托組件,基本都是布局,不多說了 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" // 我的機器貌似不支持這種字體 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) // 正為綠色,負為紅色 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" } } } ~~~ 為了支撐這個StockListView,我們還需要一個StockListModel.qml: 它同樣是一個ListModel,由許多個ListElement構成,代碼也很明了。除了name和stockId 被賦值外,value,change,changePercentage都是在view中被動態賦值的,因此均初始化為0.0。 ~~~ import QtQuick 2.0 ListModel { id: stocks // Data from : http://en.wikipedia.org/wiki/NASDAQ-100 // 這里告訴了我們數據來源 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,我們接下來就要為它添加血肉了。我在網上看到有人認為底層先于界面開發更快,也有人認為先搭界面框架再做底層更好。嗯...我倒覺得談不上好壞之分,關鍵在于動手之前得有一個清晰的架構。不過底層在設計之初能夠擁有豐富的API 減少日后改動,界面最初設計不要要求太高(因為總是會改的。。。),這樣應該會讓人比較舒服一些~ 好了,扯遠了,下面的StockView即是我們一開始看到的曲線界面,看看它包含哪些東西: ~~~ import QtQuick 2.0 import QtQuick.Window 2.1 // 下面的代碼使用了Screen因此引入這個模塊 Rectangle { id: root width: 320 height: 480 color: "transparent" property var stock: null property var stocklist: null signal settingsClicked function update() { // 用來更新圖表顯示 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 // 基于屬性綁定的屏幕轉向后布局方式的變化 anchors.rightMargin: 20 stock: root.stock } StockChart { // 右方的曲線繪制部分 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 { // 左下方的顯示設置面板 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個主要部分構成,分別是顯示當前股票信息的StockInfo、設置顯示曲線的StockSettingPanel、以及最后的繪圖部分StockChart。 我們按順序來看,StockInfo.qml: ~~~ import QtQuick 2.0 Rectangle { // 根項目是一個透明的Rectangle。為什么不用Item,我想可能是因為當時布局的時候把color設置出來可能更方便一些 id: root width: 440 height: 160 color: "transparent" property var stock: null // var類型的stock屬性,它接受的是stocqt.qml中定義的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 // 類似的,對顯示文本賦值 } 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 { // 價格 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 { // 價格變化 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 { // 價格變化百分比 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 // 對外的標志位 property bool drawClosePrice: closeButton.buttonEnabled property bool drawHighPrice: highButton.buttonEnabled property bool drawLowPrice: lowButton.buttonEnabled property string openColor: "#face20" // 各曲線的顏色設置 property string closeColor: "#14aaff" property string highColor: "#80c342" property string lowColor: "#f30000" property string volumeColor: "#14aaff" // 成交量繪制顏色 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 { // 自定義的CheckBox,提供了屬性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 } } ~~~ 自定義的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" } } } ~~~ 接著還有一個自定義的控件Button.qml,它在下面的StockChart將會用到: ~~~ import QtQuick 2.0 Rectangle { id: button signal clicked property alias text: txt.text // 設置txt.text的屬性別名為text,這樣Rectangle就不用再聲明一個屬性以訪問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 } } ~~~ 最終的繪制部分終于來了,StockChart.qml: ~~~ import QtQuick 2.0 Rectangle { id: chart width: 320 height: 200 property var stockModel: null property var startDate: new Date() // new Date()初始化得到的是當前時間 property var endDate: new Date() property string activeChart: "year" // 設置表格顯示的時間跨度為一年 property var settings property int gridSize: 4 // 每個網格寬度為4px property real gridStep: gridSize ? (width - canvas.tickMargin) / gridSize : canvas.xGridStep // 網格數為(寬度 - 最右方那一欄的寬度)/ 網格寬度,如果gridSize為0,采用畫布中的計算方式 function update() { // 更新函數 endDate = new Date(); if (chart.activeChart === "year") { // 顯示一年數據 chart.startDate = new Date(chart.endDate.getFullYear() - 1, // 在當前時間的基礎上減一年 chart.endDate.getMonth(), chart.endDate.getDate()); chart.gridSize = 12; // 設置網格寬度為12,以固定網格數 } else if (chart.activeChart === "month") { // 顯示一個月數據 chart.startDate = new Date(chart.endDate.getFullYear(), // 在當前時間基礎上減一個月 chart.endDate.getMonth() - 1, chart.endDate.getDate()); gridSize = 0; // gridSize為0時,采用canvas中定義的網格寬度計算。使每個數據都繪制在坐標線上 } else if (chart.activeChart === "week") { // 顯示一周數據 chart.startDate = new Date(chart.endDate.getFullYear(), // 在當前時間基礎上減七天 chart.endDate.getMonth(), chart.endDate.getDate() - 7); gridSize = 0; } else { chart.startDate = new Date(2005, 3, 25); // 否則以2005年為初始年,并定義網格寬度為4 gridSize = 4; } canvas.requestPaint(); // 當更新時需要調用畫布的這個函數 } Row { // Row布局了4個自定義的按鈕 id: activeChartRow anchors.left: chart.left anchors.right: chart.right anchors.top: chart.top anchors.topMargin: 4 spacing: 52 onWidthChanged: { // 該函數保證寬度變化時優先壓縮spacing,且不會造成按鈕重疊 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"; // 改變當前圖表顯示模式,這里的max 實際對應update中的'else',即2005年作為起始年 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 { // 下方的起始日期顯示 id: fromDate color: "#000000" font.family: "Open Sans" font.pointSize: 8 anchors.left: parent.left anchors.bottom: parent.bottom text: "| " + startDate.toDateString() } Text { // 結束日期顯示 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 { // 畫布,基本上與HTML的Canvas相同 id: canvas // 注釋介紹將下面兩行語句取消注釋以獲得OpenGL的硬件加速渲染,為什么沒有開?有些平臺不支持嘛... // Uncomment below lines to use OpenGL hardware accelerated rendering. // See Canvas documentation for available options. //renderTarget: Canvas.FramebufferObject // 渲染到OpenGL的幀緩沖 //renderStrategy: Canvas.Threaded // 渲染工作在一個私有渲染線程中進行 anchors.top: activeChartRow.bottom // 作為Item的派生類型,我們同樣可以設置它的布局與屬性 anchors.left: parent.left anchors.right: parent.right anchors.bottom: fromDate.top property int pixelSkip: 1 property int numPoints: 1 // 存儲數據點的個數 property int tickMargin: 32 // 右邊格的寬度 property real xGridStep: (width - tickMargin) / numPoints // 網格寬度 property real yGridOffset: height / 26 // y方向向下的偏移度,用在水平線的繪制 property real yGridStep: height / 12 // 網格高度 function drawBackground(ctx) { // 界面的繪制由onPaint開始,這是繪制背景的一個函數。ctx作為傳參,類似C++中的painter ctx.save(); // 保存之前繪制內容 ctx.fillStyle = "#ffffff"; // 填充顏色,之所以叫Style是因為它還可以使用漸變等等... ctx.fillRect(0, 0, canvas.width, canvas.height); // fillRect是一個便利函數,用來填充一個矩形區域 ctx.strokeStyle = "#d7d7d7"; // 描邊顏色 ctx.beginPath(); // 水平網格線 for (var i = 0; i < 12; i++) { ctx.moveTo(0, canvas.yGridOffset + i * canvas.yGridStep); ctx.lineTo(canvas.width, canvas.yGridOffset + i * canvas.yGridStep); } // 垂直網格線 var height = 35 * canvas.height / 36; // 垂直線的高度為畫布高度的 35/36 var yOffset = canvas.height - height; // 垂直線離頂部距離為高度的 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(); // 描線 // 右方以及下方顏色較深的那幾根線 ctx.strokeStyle = "#666666"; ctx.beginPath(); var xStart = canvas.width - tickMargin; // x = 畫布寬度 - 價格部分寬度 ctx.moveTo(xStart, 0); ctx.lineTo(xStart, canvas.height); // 向下畫直線 for (i = 0; i < 12; i++) { ctx.moveTo(xStart, canvas.yGridOffset + i * canvas.yGridStep); // 12根短橫線 ctx.lineTo(canvas.width, canvas.yGridOffset + i * canvas.yGridStep); } ctx.moveTo(0, canvas.yGridOffset + 9 * canvas.yGridStep); // 移動繪制點到第九根橫線左端 ctx.lineTo(canvas.width, canvas.yGridOffset + 9 * canvas.yGridStep); // 向右繪制橫線 ctx.closePath(); // 完成路徑 ctx.stroke(); // 描邊 ctx.restore(); // 載入保存的內容 } function drawScales(ctx, high, low, vol) // 繪制右方股票價格標尺函數 { ctx.save(); ctx.strokeStyle = "#888888"; ctx.font = "10px Open Sans" ctx.beginPath(); // prices on y-axis var x = canvas.width - tickMargin + 3; // 離右邊實線3px var priceStep = (high - low) / 9.0; // 相隔最高價與最低價的差值除以9 for (var i = 0; i < 10; i += 2) { // 隔一級顯示 var price = parseFloat(high - i * priceStep).toFixed(1); ctx.text(price, x, canvas.yGridOffset + i * yGridStep - 2); // 繪制text的坐標在文字的左下角 } // highest volume ctx.text(vol, 0, canvas.yGridOffset + 9 * yGridStep + 12); // 繪制最高成交量 ctx.closePath(); ctx.stroke(); ctx.restore(); } function drawPrice(ctx, from, to, color, price, points, highest, lowest) // 數據曲線繪制 { 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; // 數據長度 var range = highest - lowest; // 取值范圍 if (range == 0) { range = 1; // range作為被除數不能為0 } for (var i = 0; i < end; i += pixelSkip) { var x = points[i].x; var y = points[i][price]; // 取出對應設置的價格數據 var h = 9 * yGridStep; // 設置繪制高度為九倍的網格高度 y = h * (lowest - y)/range + h + yGridOffset; // lowest - y為非正數,h + yGridOffset為曲線繪制的底部 if (i == 0) { ctx.moveTo(x, y); // 移動到初始點 } else { ctx.lineTo(x, y); // 向后繪制 } } ctx.stroke(); ctx.restore(); } function drawVolume(ctx, from, to, color, price, points, highest) // 成交量繪制函數 { ctx.save(); ctx.fillStyle = color; ctx.globalAlpha = 0.8; ctx.lineWidth = 0; // 由于線寬影響繪制邊界(參考HTML),這里將線寬設置為0 ctx.beginPath(); var end = points.length; var margin = 0; if (chart.activeChart === "month" || chart.activeChart === "week") { margin = 8; ctx.shadowOffsetX = 4; // x方向的陰影 ctx.shadowBlur = 3.5; // 模糊效果 ctx.shadowColor = Qt.darker(color); } // 由于柱狀圖的寬度限制,柱狀圖比實際的數據少一個 // 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; // 柱狀圖高度占畫布的1/4 ctx.fillRect(x, canvas.height - y + yGridOffset, canvas.xGridStep - margin, y); // "周"與"月"時有間隔,其他則沒有 } ctx.stroke(); ctx.restore(); } onPaint: { // 繪制入口 if (!stockModel.ready) { // 等待數據完成 return; } numPoints = stockModel.indexOf(chart.startDate); // 由StockModel取得startDate到現在的數據數 if (chart.gridSize == 0) chart.gridSize = numPoints // 使gridStep綁定到(width - canvas.tickMargin) / numPoints上 var ctx = canvas.getContext("2d"); // 創建ctx ctx.globalCompositeOperation = "source-over"; // 混合模式 ctx.lineWidth = 1; drawBackground(ctx); // 背景繪制 var highestPrice = 0; var highestVolume = 0; var lowestPrice = -1; var points = []; // 創建一個數組 for (var i = numPoints, j = 0; i >= 0 ; i -= pixelSkip, j += pixelSkip) { // pixelSkip被定義為 1 var price = stockModel.get(i); if (parseFloat(highestPrice) < parseFloat(price.high)) // 得到最高價 highestPrice = price.high; if (parseInt(highestVolume, 10) < parseInt(price.volume, 10)) // 得到最低價 highestVolume = price.volume; if (lowestPrice < 0 || parseFloat(lowestPrice) > parseFloat(price.low)) // 注意這里如果設置lowestPrice = 0或是別的數 lowestPrice = price.low; // 就有可能一直無法滿足條件,因此添加這個負數使第一個price.low被賦予lowestPrice points.push({ // 插入數據,它類似于Model,但多了一個 x 的坐標值 x: j * xGridStep, open: price.open, close: price.close, high: price.high, low: price.low, volume: price.volume }); } if (settings.drawHighPrice) // 判斷StockSettingPanel中相應的選項是否被勾選,然后繪制數據線段 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); // 成交量繪制 drawScales(ctx, highestPrice, lowestPrice, highestVolume); // 價格標尺繪制 } } } ~~~
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