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html5 canvas touch(html5 canvas手势解锁源码分享)

更多 时间:2021-10-08 00:48:21 类别:Web前端 浏览量:1918

html5 canvas touch

html5 canvas手势解锁源码分享

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html5 canvas touch(html5 canvas手势解锁源码分享)

html5 canvas touch(html5 canvas手势解锁源码分享)

demo.html

  • <!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">
            // 1、生成背景
            // 2、title生成
            // 3、用js动态生成canvas标签
            // 4、js方式动态生成h4标签和canvas标签
            new canvasLock({chooseType:3}).init();
        </script>
    </body>
    </html>
    
  • index.js

  • (function(){
            /**
             * 实现画圆和划线:
             * 1、添加事件touchstart、touchmove、touchend
             * 2、touchstart判断是否点击的位置处于圆内getPosition,处于则初始化
             * lastpoint、restPoint
             * 3、touchmove做的就是:画圆drawPoint和画线drawLine
             *
             * 实现自动画圆的效果
             * 1、检测手势移动的位置是否处于圆内
             * 2、圆内的话则画圆 drawPoint
             * 3、已经画过实心圆的圆,无需重复检测
             *
             * 实现解锁成功:
             * 1、检测路径是否是对的
             * 2、如果是对的就重置,圆圈变绿
             * 3、不对也重置,圆圈变红
             * 4、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('li');
                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() {// 创建解锁点的坐标,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;
                // 1、确定半径
                // 2、确定每一个圆的中心坐标点
                // 3、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) {
                    // 2、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,并且是相较于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做的就是: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);
    
                // 重新画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
    
                // 1、检测手势移动的位置是否处于下一个圆内
                // 2、圆内的话则画圆 drawPoint
                // 3、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();
                }
            }
    
            // 1、检测路径是否是对的
            // 2、如果是对的就重置,圆圈变绿
            // 3、不对也重置,圆圈变红
            // 4、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();
            }
    })();
    
  • 总结

    以上所述是小编给大家介绍的html5 canvas手势解锁源码分享,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对开心学习网网站的支持!
    如果你觉得本文对你有帮助,欢迎转载,烦请注明出处,谢谢!

    标签:解锁 Canvas HTML5