Question

一旦用户单击“蒙版图像”，我们就会显示文件上传对话框。...

我们使用以下代码进行点击：

$('.container').click(function(e) {

        var res = e.target;
        target = res.id;
        console.log(target);
        if (e.target.getContext) {
            // click only inside Non Transparent part
            var pixel = e.target.getContext('2d').getImageData(e.offsetX, e.offsetY, 1, 1).data;
            if (pixel[3] === 255) {
                setTimeout(() => {
                    $('#fileup').click();
                }, 20);
            }
        }
    });

问题：

由于某些原因而不是上面的代码，我们使用下面的代码进行点击：

$('.container').click(function(e) {
        // filtering out non-canvas clicks
        if (e.target.tagName !== 'CANVAS') return;

        // getting absolute points relative to container
        const absX = e.offsetX + e.target.parentNode.offsetLeft + e.currentTarget.offsetLeft;
        const absY = e.offsetY + e.target.parentNode.offsetTop + e.currentTarget.offsetTop;

        const $canvasList = $(this).find('canvas');
        // moving all canvas parents on the same z-index
        $canvasList.parent().css({
            zIndex: 0
        });

        $canvasList.filter(function() { // filtering only applicable canvases
            const bbox = this.getBoundingClientRect()
            return (
                absX >= bbox.left && absX <= bbox.left + bbox.width &&
                absY >= bbox.top && absY <= bbox.top + bbox.height)
        }).each(function() { // checking white in a click position
            const x = absX - this.parentNode.offsetLeft - e.currentTarget.offsetLeft;
            const y = absY - this.parentNode.offsetTop - e.currentTarget.offsetTop;
            const pixel = this.getContext('2d').getImageData(x, y, 1, 1).data;
            if (pixel[3] === 255) {
                $(this).parent().css({
                    zIndex: 2
                })
                target = this.id;
                console.log(target);
                setTimeout(() => {
                    $('#fileup').click();
                }, 20);
            }
        })
    });

但是现在，当用户单击第二张图像的底部时，则不允许像https://codepen.io/kidsdial/pen/LvpLYo中那样上传图像。...

案例：

1。如果单击第二张图像的底部，它将无法在Codepen中工作。...

2。如果您复制相同的代码并在本地PC上尝试，则可以使用...。但是，如果打开inspect元素，则无法使用...。[可能是由于高度减少]

3。如果您“运行代码段并点击第二张图片的底部，则它不起作用，但是如果您以” 全页模式”打开，则它将起作用，如果您在此处打开检查元素，那么它将不起作用。...

var target;
let jsonData = {
    "layers": [{
        "x": 0,
        "height": 612,
        "layers": [{
                "x": 0,
                "y": 0,
                "name": "L2a"
            },
            {
                "x": 160,
                "layers": [{
                        "x": 0,
                        "src": "ax0HVTs.png",
                        "y": 0,
                        "name": "L2b-1"
                    },
                    {

                        "x": 0,
                        "y": 0,
                        "name": "L2b-2"
                    }
                ],
                "y": 291,
                "name": "user_image_1"
            },
            {
                "x": 25,
                "layers": [{
                        "x": 0,
                        "src": "hEM2kEP.png",
                        "y": 0,
                        "name": "L2C-1"
                    },
                    {
                        "x": 0,
                        "y": 0,
                        "name": "L2C-2"
                    }
                ],
                "y": 22,
                "name": "L2"
            }
        ],
        "y": 0,
        "width": 612,
        "name": "L1"
    }]
};

$(document).ready(function() {

    // upload image onclick

    $('.container').click(function(e) {
        // filtering out non-canvas clicks
        if (e.target.tagName !== 'CANVAS') return;

        // getting absolute points relative to container
        const absX = e.offsetX + e.target.parentNode.offsetLeft + e.currentTarget.offsetLeft;
        const absY = e.offsetY + e.target.parentNode.offsetTop + e.currentTarget.offsetTop;

        const $canvasList = $(this).find('canvas');
        // moving all canvas parents on the same z-index
        $canvasList.parent().css({
            zIndex: 0
        });

        $canvasList.filter(function() { // filtering only applicable canvases
            const bbox = this.getBoundingClientRect()
            return (
                absX >= bbox.left && absX <= bbox.left + bbox.width &&
                absY >= bbox.top && absY <= bbox.top + bbox.height)
        }).each(function() { // checking white in a click position
            const x = absX - this.parentNode.offsetLeft - e.currentTarget.offsetLeft;
            const y = absY - this.parentNode.offsetTop - e.currentTarget.offsetTop;
            const pixel = this.getContext('2d').getImageData(x, y, 1, 1).data;
            if (pixel[3] === 255) {
                $(this).parent().css({
                    zIndex: 2
                })
                target = this.id;
                console.log(target);
                setTimeout(() => {
                    $('#fileup').click();
                }, 20);
            }
        })
    });
    

    //Fetch images from json

    function getAllSrc(layers) {
        let arr = [];
        layers.forEach(layer => {
            if (layer.src) {
                arr.push({
                    src: layer.src,
                    x: layer.x,
                    y: layer.y
                });
            } else if (layer.layers) {
                let newArr = getAllSrc(layer.layers);
                if (newArr.length > 0) {
                    newArr.forEach(({
                        src,
                        x,
                        y
                    }) => {
                        arr.push({
                            src,
                            x: (layer.x + x),
                            y: (layer.y + y)
                        });
                    });
                }
            }
        });
        return arr;
    }

    function json(data)

    {
        var width = 0;
        var height = 0;

        let arr = getAllSrc(data.layers);

        let layer1 = data.layers;
        width = layer1[0].width;
        height = layer1[0].height;
        let counter = 0;
        let table = [];

        for (let {
                src,
                x,
                y
            } of arr) {

            $(".container").css('width', width + "px").css('height', height + "px").addClass('temp');

            var mask = $(".container").mask({
                maskImageUrl: 'https://i.imgur.com/' + src,
                onMaskImageCreate: function(img) {

                    img.css({
                        "position": "absolute",
                        "left": x + "px",
                        "top": y + "px"
                    });

                },
                id: counter
            });
            table.push(mask);
            fileup.onchange = function() {

                let mask2 = table[target];
                mask2.loadImage(URL.createObjectURL(fileup.files[0]));
                document.getElementById('fileup').value = "";
            };
            counter++;
        }

    }

    json(jsonData);
}); // end of document ready

// jq plugin 

(function($) {
    var JQmasks = [];
    $.fn.mask = function(options) {
        // This is the easiest way to have default options.
        var settings = $.extend({
            // These are the defaults.
            maskImageUrl: undefined,
            imageUrl: undefined,
            scale: 1,
            id: new Date().getUTCMilliseconds().toString(),
            x: 0, // image start position
            y: 0, // image start position
            onMaskImageCreate: function(div) {},
        }, options);


        var container = $(this);

        let prevX = 0,
            prevY = 0,
            draggable = false,
            img,
            canvas,
            context,
            image,
            timeout,
            initImage = false,
            startX = settings.x,
            startY = settings.y,
            div;

        container.mousePosition = function(event) {
            return {
                x: event.pageX || event.offsetX,
                y: event.pageY || event.offsetY
            };
        }

        container.selected = function(ev) {
            var pos = container.mousePosition(ev);
            var item = $(".masked-img canvas").filter(function() {
                var offset = $(this).offset()
                var x = pos.x - offset.left;
                var y = pos.y - offset.top;
                var d = this.getContext('2d').getImageData(x, y, 1, 1).data;
                return d[0] > 0
            });

            JQmasks.forEach(function(el) {
                var id = item.length > 0 ? $(item).attr("id") : "";
                if (el.id == id)
                    el.item.enable();
                else el.item.disable();
            });
        };

        container.enable = function() {
            draggable = true;
            $(canvas).attr("active", "true");
            div.css({
                "z-index": 2
            });
        }

        container.disable = function() {
            draggable = false;
            $(canvas).attr("active", "false");
            div.css({
                "z-index": 1
            });
        }

        container.updateStyle = function() {
            clearTimeout(timeout);
            timeout = setTimeout(function() {
                //context.clearRect(0, 0, canvas.width, canvas.height);
                context.beginPath();
                context.globalCompositeOperation = "source-over";
                image = new Image();
                image.setAttribute('crossOrigin', 'anonymous');
                image.src = settings.maskImageUrl;
                image.onload = function() {
                    canvas.width = image.width;
                    canvas.height = image.height;
                    context.drawImage(image, 0, 0, image.width, image.height);
                    div.css({
                        "width": image.width,
                        "height": image.height
                    });
                };

                img = new Image();
                img.src = settings.imageUrl;
                img.setAttribute('crossOrigin', 'anonymous');
                img.onload = function() {
                    settings.x = settings.x == 0 && initImage ? (canvas.width - (img.width * settings.scale)) / 2 : settings.x;
                    settings.y = settings.y == 0 && initImage ? (canvas.height - (img.height * settings.scale)) / 2 : settings.y;
                    context.globalCompositeOperation = 'source-atop';
                    context.drawImage(img, settings.x, settings.y, img.width * settings.scale, img.height * settings.scale);
                    initImage = false;
                };
            }, 20);
        };

        // change the draggable image
        container.loadImage = function(imageUrl) {
            console.log("load");
            if (img)
                img.remove();
            // reset the code.
            settings.y = startY;
            settings.x = startX;
            prevX = prevY = 0;
            settings.imageUrl = imageUrl;
            initImage = true;
            container.updateStyle();
        };

        // change the masked Image
        container.loadMaskImage = function(imageUrl, from) {
            if (div)
                div.remove();
            canvas = document.createElement("canvas");
            context = canvas.getContext('2d');
            canvas.setAttribute("draggable", "true");
            canvas.setAttribute("id", settings.id);
            settings.maskImageUrl = imageUrl;
            div = $("<div/>", {
                "class": "masked-img"
            }).append(canvas);

            // div.find("canvas").on('touchstart mousedown', function(event)
            div.find("canvas").on('dragstart', function(event) {

                if (event.handled === false) return;
                event.handled = true;
                container.onDragStart(event);
            });

            div.find("canvas").on('touchend mouseup', function(event) {
                if (event.handled === false) return;
                event.handled = true;
                container.selected(event);
            });

            div.find("canvas").bind("dragover", container.onDragOver);
            container.append(div);
            if (settings.onMaskImageCreate)
                settings.onMaskImageCreate(div);
            container.loadImage(settings.imageUrl);
        };
        container.loadMaskImage(settings.maskImageUrl);
        JQmasks.push({
            item: container,
            id: settings.id
        })
        return container;
    };
}(jQuery));

.temp {
background: black;
}

.container {
	background: gold;
  position: relative;
 
}

.masked-img {
	overflow: hidden;
	
	position: relative;
}

<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>

<input id="fileup" name="fileup" type="file" style="display:none" >

<div class="container">

</div>

Answer 1

这是由于滚动位置已更改，并且边框的计算独立于此。我已经用

修复了脚本

        $canvasList.filter(function() { // filtering only applicable canvases
            const bbox = this.getBoundingClientRect();
            const canvasTop = bbox.top + window.scrollY;
            const canvasLeft = bbox.left + window.scrollX;
            return (
                absX >= canvasLeft && absX <= canvasLeft + bbox.width &&
                absY >= canvasTop && absY <= canvasTop + bbox.height)
        })

注意1：不过，这也可以通过为画布父元素放置的位置数据来解决。注意2：如果滚动容器不同，则应放置正确的容器而不是window（当前是相同的）。

var target;
let jsonData = {
    "layers": [{
        "x": 0,
        "height": 612,
        "layers": [{
                "x": 0,
                "y": 0,
                "name": "L2a"
            },
            {
                "x": 160,
                "layers": [{
                        "x": 0,
                        "src": "ax0HVTs.png",
                        "y": 0,
                        "name": "L2b-1"
                    },
                    {

                        "x": 0,
                        "y": 0,
                        "name": "L2b-2"
                    }
                ],
                "y": 291,
                "name": "user_image_1"
            },
            {
                "x": 25,
                "layers": [{
                        "x": 0,
                        "src": "hEM2kEP.png",
                        "y": 0,
                        "name": "L2C-1"
                    },
                    {
                        "x": 0,
                        "y": 0,
                        "name": "L2C-2"
                    }
                ],
                "y": 22,
                "name": "L2"
            }
        ],
        "y": 0,
        "width": 612,
        "name": "L1"
    }]
};

$(document).ready(function() {

    // upload image onclick

    $('.container').click(function(e) {
        // filtering out non-canvas clicks

        if (e.target.tagName !== 'CANVAS') return;

        // getting absolute points relative to container
        const absX = e.offsetX + e.target.parentNode.offsetLeft + e.currentTarget.offsetLeft;
        const absY = e.offsetY + e.target.parentNode.offsetTop + e.currentTarget.offsetTop;

        const $canvasList = $(this).find('canvas');
        // moving all canvas parents on the same z-index
        $canvasList.parent().css({
            zIndex: 0
        });

        $canvasList.filter(function() { // filtering only applicable canvases
            const bbox = this.getBoundingClientRect();
            const canvasTop = bbox.top + window.scrollY;
            const canvasLeft = bbox.left + window.scrollX;
            return (
                absX >= canvasLeft && absX <= canvasLeft + bbox.width &&
                absY >= canvasTop && absY <= canvasTop + bbox.height)
        }).each(function() { // checking white in a click position
            const x = absX - this.parentNode.offsetLeft - e.currentTarget.offsetLeft;
            const y = absY - this.parentNode.offsetTop - e.currentTarget.offsetTop;
            const pixel = this.getContext('2d').getImageData(x, y, 1, 1).data;
            if (pixel[3] === 255) {
                $(this).parent().css({
                    zIndex: 2
                })
                target = this.id;
                console.log(target);
                //setTimeout(() => {
                  //  $('#fileup').click();
                //}, 20);
            }
        })
    });
    

    //Fetch images from json

    function getAllSrc(layers) {
        let arr = [];
        layers.forEach(layer => {
            if (layer.src) {
                arr.push({
                    src: layer.src,
                    x: layer.x,
                    y: layer.y
                });
            } else if (layer.layers) {
                let newArr = getAllSrc(layer.layers);
                if (newArr.length > 0) {
                    newArr.forEach(({
                        src,
                        x,
                        y
                    }) => {
                        arr.push({
                            src,
                            x: (layer.x + x),
                            y: (layer.y + y)
                        });
                    });
                }
            }
        });
        return arr;
    }

    function json(data)

    {
        var width = 0;
        var height = 0;

        let arr = getAllSrc(data.layers);

        let layer1 = data.layers;
        width = layer1[0].width;
        height = layer1[0].height;
        let counter = 0;
        let table = [];

        for (let {
                src,
                x,
                y
            } of arr) {

            $(".container").css('width', width + "px").css('height', height + "px").addClass('temp');

            var mask = $(".container").mask({
                maskImageUrl: 'https://i.imgur.com/' + src,
                onMaskImageCreate: function(img) {

                    img.css({
                        "position": "absolute",
                        "left": x + "px",
                        "top": y + "px"
                    });

                },
                id: counter
            });
            table.push(mask);
            fileup.onchange = function() {

                let mask2 = table[target];
                mask2.loadImage(URL.createObjectURL(fileup.files[0]));
                document.getElementById('fileup').value = "";
            };
            counter++;
        }

    }

    json(jsonData);
}); // end of document ready

// jq plugin 

(function($) {
    var JQmasks = [];
    $.fn.mask = function(options) {
        // This is the easiest way to have default options.
        var settings = $.extend({
            // These are the defaults.
            maskImageUrl: undefined,
            imageUrl: undefined,
            scale: 1,
            id: new Date().getUTCMilliseconds().toString(),
            x: 0, // image start position
            y: 0, // image start position
            onMaskImageCreate: function(div) {},
        }, options);


        var container = $(this);

        let prevX = 0,
            prevY = 0,
            draggable = false,
            img,
            canvas,
            context,
            image,
            timeout,
            initImage = false,
            startX = settings.x,
            startY = settings.y,
            div;

        container.mousePosition = function(event) {
            return {
                x: event.pageX || event.offsetX,
                y: event.pageY || event.offsetY
            };
        }

        container.selected = function(ev) {
            var pos = container.mousePosition(ev);
            var item = $(".masked-img canvas").filter(function() {
                var offset = $(this).offset()
                var x = pos.x - offset.left;
                var y = pos.y - offset.top;
                var d = this.getContext('2d').getImageData(x, y, 1, 1).data;
                return d[0] > 0
            });

            JQmasks.forEach(function(el) {
                var id = item.length > 0 ? $(item).attr("id") : "";
                if (el.id == id)
                    el.item.enable();
                else el.item.disable();
            });
        };

        container.enable = function() {
            draggable = true;
            $(canvas).attr("active", "true");
            div.css({
                "z-index": 2
            });
        }

        container.disable = function() {
            draggable = false;
            $(canvas).attr("active", "false");
            div.css({
                "z-index": 1
            });
        }

        container.updateStyle = function() {
            clearTimeout(timeout);
            timeout = setTimeout(function() {
                //context.clearRect(0, 0, canvas.width, canvas.height);
                context.beginPath();
                context.globalCompositeOperation = "source-over";
                image = new Image();
                image.setAttribute('crossOrigin', 'anonymous');
                image.src = settings.maskImageUrl;
                image.onload = function() {
                    canvas.width = image.width;
                    canvas.height = image.height;
                    context.drawImage(image, 0, 0, image.width, image.height);
                    div.css({
                        "width": image.width,
                        "height": image.height
                    });
                };

                img = new Image();
                img.src = settings.imageUrl;
                img.setAttribute('crossOrigin', 'anonymous');
                img.onload = function() {
                    settings.x = settings.x == 0 && initImage ? (canvas.width - (img.width * settings.scale)) / 2 : settings.x;
                    settings.y = settings.y == 0 && initImage ? (canvas.height - (img.height * settings.scale)) / 2 : settings.y;
                    context.globalCompositeOperation = 'source-atop';
                    context.drawImage(img, settings.x, settings.y, img.width * settings.scale, img.height * settings.scale);
                    initImage = false;
                };
            }, 20);
        };

        // change the draggable image
        container.loadImage = function(imageUrl) {
            console.log("load");
            if (img)
                img.remove();
            // reset the code.
            settings.y = startY;
            settings.x = startX;
            prevX = prevY = 0;
            settings.imageUrl = imageUrl;
            initImage = true;
            container.updateStyle();
        };

        // change the masked Image
        container.loadMaskImage = function(imageUrl, from) {
            if (div)
                div.remove();
            canvas = document.createElement("canvas");
            context = canvas.getContext('2d');
            canvas.setAttribute("draggable", "true");
            canvas.setAttribute("id", settings.id);
            settings.maskImageUrl = imageUrl;
            div = $("<div/>", {
                "class": "masked-img"
            }).append(canvas);

            // div.find("canvas").on('touchstart mousedown', function(event)
            div.find("canvas").on('dragstart', function(event) {

                if (event.handled === false) return;
                event.handled = true;
                container.onDragStart(event);
            });

            div.find("canvas").on('touchend mouseup', function(event) {
                if (event.handled === false) return;
                event.handled = true;
                container.selected(event);
            });

            div.find("canvas").bind("dragover", container.onDragOver);
            container.append(div);
            if (settings.onMaskImageCreate)
                settings.onMaskImageCreate(div);
            container.loadImage(settings.imageUrl);
        };
        container.loadMaskImage(settings.maskImageUrl);
        JQmasks.push({
            item: container,
            id: settings.id
        })
        return container;
    };
}(jQuery));

.temp {
background: black;
}

.container {
	background: gold;
  position: relative;
 
}

.masked-img {
	overflow: hidden;
	
	position: relative;
}

<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>

<input id="fileup" name="fileup" type="file" style="display:none" >

<div class="container">

</div>

使用检查元素上传图像

1 个答案: