canvas手势解锁源码

时间 2020-05-20

标签 canvas 手势解锁源码繁體版

原文原文链接

先放图javascript

demo.htmlcss

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
    <title>手势解锁</title>
    <style type="text/css"> body{ text-align: center; background: #305066;
        } h4{ color: #22C3AA;
        }
    </style>
</head>
<body>
    <script type="text/javascript" src="src/index.js"></script>
    <script type="text/javascript">
        // 一、生成背景
        // 二、title生成
        // 三、用js动态生成canvas标签
        // 四、js方式动态生成h4标签和canvas标签
        new canvasLock({chooseType:3}).init(); </script>
</body>
</html>

index.jshtml

(function(){ /** * 实现画圆和划线： * 一、添加事件touchstart、touchmove、touchend * 二、touchstart判断是否点击的位置处于圆内getPosition，处于则初始化 * lastpoint、restPoint * 三、touchmove作的就是：画圆drawPoint和画线drawLine * * 实现自动画圆的效果 * 一、检测手势移动的位置是否处于圆内 * 二、圆内的话则画圆 drawPoint * 三、已经画过实心圆的圆，无需重复检测 * * 实现解锁成功： * 一、检测路径是不是对的 * 二、若是是对的就重置，圆圈变绿 * 三、不对也重置，圆圈变红 * 四、重置 */ window.canvasLock = function(obj){ this.height = obj.height; this.width = obj.width; this.chooseType = obj.chooseType; }; // js方式动态生成dom
        canvasLock.prototype.initDom = function(){ var wrap = document.createElement('div'); var str = '<h4 id="title" class="title">绘制解锁图案</h4>'; wrap.setAttribute('style','position: absolute;top:0;left:0;right:0;bottom:0;'); var canvas = document.createElement('canvas'); canvas.setAttribute('id','canvas'); canvas.style.cssText = 'background-color: #305066;display: inline-block;margin-top: 15px;'; wrap.innerHTML = str; wrap.appendChild(canvas); var width = this.width || 300; var height = this.height || 300; document.body.appendChild(wrap); // 高清屏锁放
            canvas.style.width = width + "px"; canvas.style.height = height + "px"; canvas.width = width; canvas.height = height; } canvasLock.prototype.drawCle = function(x, y) { // 初始化解锁密码面板
            this.ctx.strokeStyle = '#CFE6FF'; this.ctx.lineWidth = 2; this.ctx.beginPath(); this.ctx.arc(x, y, this.r, 0, Math.PI * 2, true); this.ctx.closePath(); this.ctx.stroke(); } canvasLock.prototype.createCircle = function() {// 建立解锁点的坐标，根据canvas的大小来平均分配半径

            var n = this.chooseType; var count = 0; this.r = this.ctx.canvas.width / (2 + 4 * n);// 公式计算
            this.lastPoint = []; this.arr = []; this.restPoint = []; var r = this.r; for (var i = 0 ; i < n ; i++) { for (var j = 0 ; j < n ; j++) { count++; var obj = { x: j * 4 * r + 3 * r, y: i * 4 * r + 3 * r, index: count }; this.arr.push(obj); this.restPoint.push(obj); } } this.ctx.clearRect(0, 0, this.ctx.canvas.width, this.ctx.canvas.height); for (var i = 0 ; i < this.arr.length ; i++) { // 画圆函数
                this.drawCle(this.arr[i].x, this.arr[i].y); } //return arr;
 } // 程序初始化
        canvasLock.prototype.init = function() { this.initDom(); this.canvas = document.getElementById('canvas'); this.ctx = this.canvas.getContext('2d'); this.touchFlag = false; // 一、肯定半径
            // 二、肯定每个圆的中心坐标点
            // 三、一行3个圆14个半径，一行4个圆有18个半径
            this.createCircle(); this.bindEvent(); } canvasLock.prototype.bindEvent = function(){ var self = this; this.canvas.addEventListener("touchstart", function (e) { // 二、touchstart判断是否点击的位置处于圆内getPosition，处于则初始化
                // * lastpoint、restPoint
                
                // po有x和y，而且是相较于canvas边距
                var po = self.getPosition(e); console.log(po.x) // 判断是否在圆内的原理：多出来的这条 x/y < r 在圆内
                for (var i = 0 ; i < self.arr.length ; i++) { if (Math.abs(po.x - self.arr[i].x) < self.r && Math.abs(po.y - self.arr[i].y) < self.r) { self.touchFlag = true; // lastPoint存放的就是选中的圆圈的x/y坐标值
 self.lastPoint.push(self.arr[i]); self.restPoint.splice(i,1); break; } } }, false); this.canvas.addEventListener("touchmove", function (e) { // touchmove作的就是：画圆drawPoint和划线drawLine
               if (self.touchFlag) { self.update(self.getPosition(e)); } }, false); this.canvas.addEventListener("touchend", function(e){ if (self.touchFlag) { self.storePass(self.lastPoint); setTimeout(function(){ self.reset(); }, 300); } }, false); } canvasLock.prototype.getPosition = function(e) {// 获取touch点相对于canvas的坐标
            var rect = e.currentTarget.getBoundingClientRect(); var po = { x: (e.touches[0].clientX - rect.left), y: (e.touches[0].clientY - rect.top) }; return po; } canvasLock.prototype.update = function(po) {// 核心变换方法在touchmove时候调用
            this.ctx.clearRect(0, 0, this.ctx.canvas.width, this.ctx.canvas.height); // 从新画9个圆圈
            for (var i = 0 ; i < this.arr.length ; i++) { // 每帧先把面板画出来
                this.drawCle(this.arr[i].x, this.arr[i].y); } this.drawPoint();// 画圆
            this.drawLine(po);// 画线

            // 一、检测手势移动的位置是否处于下一个圆内
            // 二、圆内的话则画圆 drawPoint
            // 三、已经画过实心圆的圆，无需重复检测
            for (var i = 0 ; i < this.restPoint.length ; i++) { if (Math.abs(po.x - this.restPoint[i].x) < this.r && Math.abs(po.y - this.restPoint[i].y) < this.r) { this.drawPoint(); this.lastPoint.push(this.restPoint[i]); this.restPoint.splice(i, 1); break; } } console.log(this.lastPoint) } canvasLock.prototype.drawLine = function(po) {// 解锁轨迹
            this.ctx.beginPath(); this.ctx.lineWidth = 3; this.ctx.moveTo(this.lastPoint[0].x, this.lastPoint[0].y); for (var i = 1 ; i < this.lastPoint.length ; i++) { this.ctx.lineTo(this.lastPoint[i].x, this.lastPoint[i].y); } this.ctx.lineTo(po.x, po.y); this.ctx.stroke(); this.ctx.closePath(); } canvasLock.prototype.drawPoint = function() { // 初始化圆心 
            for (var i = 0 ; i < this.lastPoint.length ; i++) { this.ctx.fillStyle = '#CFE6FF'; this.ctx.beginPath(); this.ctx.arc(this.lastPoint[i].x, this.lastPoint[i].y, this.r / 2, 0, Math.PI * 2, true); this.ctx.closePath(); this.ctx.fill(); } } // 一、检测路径是不是对的
        // 二、若是是对的就重置，圆圈变绿
        // 三、不对也重置，圆圈变红
        // 四、重置
        canvasLock.prototype.storePass = function() { if (this.checkPass()) { document.getElementById('title').innerHTML = '解锁成功'; this.drawStatusPoint('#2CFF26'); }else{ document.getElementById('title').innerHTML = '解锁失败'; this.drawStatusPoint('red'); } } canvasLock.prototype.checkPass = function() { var p1 = '123', p2 = ''; for (var i = 0 ; i < this.lastPoint.length ; i++) { p2 += this.lastPoint[i].index; } return p1 === p2; } canvasLock.prototype.drawStatusPoint = function(type) { for (var i = 0 ; i < this.lastPoint.length ; i++) { this.ctx.strokeStyle = type; this.ctx.beginPath(); this.ctx.arc(this.lastPoint[i].x, this.lastPoint[i].y, this.r, 0, Math.PI * 2, true); this.ctx.closePath(); this.ctx.stroke(); } } canvasLock.prototype.reset = function(){ this.createCircle(); } })();