我正在使用kineticjs和html5在android phonegap应用程序中进行项目 我有3个错误，不知道究竟是什么问题
我谷歌但却找不到答案，所以任何帮助都会很棒
function clearCanvas() {
layer.removeChildren();
layer.draw();
haveBackground = false;
}
function downloadCanvas() {
var canvas = stage.children[0].canvas;
var oImgPNG = Canvas2Image.saveAsPNG(canvas, true);
document.body.appendChild(oImgPNG);
}
<img alt="" src="res/drawable-hdpi/design15.png" id="gabby" onClick="addClickedImage('gabby ')"/><br />
在我收到错误的那些片段之上。谢谢 这是我的程序的脚本
<script type="text/javascript" src="http://d3lp1msu2r81bx.cloudfront.net/kjs/js/lib/kinetic-v4.3.1.js"></script>
<script type="text/javascript" src="assets/www/base64.js"></script>
<script type="text/javascript" src="assets/www/canvas2image.js"></script>
<script type="text/javascript">
debugger;
var stage;
var layer;
var selected;
var wasSelected;
var haveBackground; // first dragged image sets stage size
/*
* Set up canvas stage and layer
*/
function initCanvas(id) {
stage = new Kinetic.Stage({
container: id,
width: 150,
height: 50
});
layer = new Kinetic.Layer();
stage.add(layer);
stage.draw();
}
/*
* Clear canvas, start again
*/
function clearCanvas() {
layer.removeChildren();
layer.draw();
haveBackground = false;
}
/*
* Download canvas
*/
function downloadCanvas() {
var canvas = stage.children[0].canvas;
var oImgPNG = Canvas2Image.saveAsPNG(canvas, true);
document.body.appendChild(oImgPNG);
}
/*
* Upload File
*/
function readURL(input) {
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$('#blah')
.attr('src', e.target.result)
.width(20)
.height(20);
};
reader.readAsDataURL(input.files[0]);
}
}
/*
* Resize
*/
function resize(group, activeAnchor) {
var tl = group.get(".tl")[0];
var tr = group.get(".tr")[0]; group
var br = group.get(".br")[0];
var bl = group.get(".bl")[0];
var handle = group.get(".handle")[0];
var ghost = group.get(".ghost")[0];
var flip = group.get(".flip")[0];
var image = group.get(".image")[0];
switch (activeAnchor.attrs.name) {
case "tl":
bl.setPosition(tl.attrs.x, br.attrs.y);
tr.setPosition(br.attrs.x, tl.attrs.y);
break;
case "tr":
br.setPosition(tr.attrs.x, bl.attrs.y);
tl.setPosition(bl.attrs.x, tr.attrs.y);
break;
case "bl":
br.setPosition(tr.attrs.x, bl.attrs.y);
tl.setPosition(bl.attrs.x, tr.attrs.y);
break;
case "br":
bl.setPosition(tl.attrs.x, br.attrs.y);
tr.setPosition(br.attrs.x, tl.attrs.y);
break;
}
handle.setPosition((tr.attrs.x + tl.attrs.x) / 2, tl.attrs.y - 20);
ghost.setPosition(handle.getPosition());
flip.setPosition((tr.attrs.x + tl.attrs.x) / 2, bl.attrs.y + 20);
image.setPosition(tl.attrs.x, tl.attrs.y);
image.attrs.width = tr.attrs.x - tl.attrs.x;
image.attrs.height = bl.attrs.y - tl.attrs.y;
}
/*
* Rotate
*/
function rotate(group) {
var c = group.getAbsolutePosition();
var p0 = { x: c.x, y: c.y - 50 };
var p1 = stage.getUserPosition();
var p0c = Math.sqrt(Math.pow(c.x - p0.x, 2) + Math.pow(c.y - p0.y, 2)); // p0->c (b)
var p1c = Math.sqrt(Math.pow(c.x - p1.x, 2) + Math.pow(c.y - p1.y, 2)); // p1->c (a)
var p0p1 = Math.sqrt(Math.pow(p1.x - p0.x, 2) + Math.pow(p1.y - p0.y, 2)); // p0->p1 (c)
var deg = Math.acos((p1c * p1c + p0c * p0c - p0p1 * p0p1) / (2 * p1c * p0c));
// fix for negative rotation
if (p1.x < c.x) {
deg = (360 * (Math.PI / 180)) - deg;
}
group.setRotation(deg);
}
/*
* Flip
*/
function flip(group) {
group.attrs.scale.x = group.attrs.scale.x * -1;
}
/*
* Fix center offset (due to resizing from a corner)
*/
function fixCenterOffset(group) {
var image = group.get(".image")[0]
var currentOffset = group.getCenterOffset();
var currentPosition = group.getPosition();
var newOffset = { x: image.attrs.width / 2, y: image.attrs.height / 2 };
var newPosition = {
x: currentPosition.x - (currentOffset.x - newOffset.x),
y: currentPosition.y - (currentOffset.y - newOffset.y)
}
group.setCenterOffset(newOffset);
group.setPosition(newPosition);
layer.draw();
}
/*
* Prepare background image
*/
function prepareBackground(img) {
var maxWidth = 200;
var maxHeight = 100;
if (img.width > maxWidth) {
img.height = (maxWidth / img.width) * img.height;
img.width = maxWidth;
}
if (img.height > maxHeight) {
img.width = (maxHeight / img.height) * img.width;
img.height = maxHeight;
}
return img;
}
/*
* Add an image plus anchors to the canvas using group
*/
function initImage(img, type) {
if (type == "background") {
var kimggroup = initBackgroundImage(img);
} else {
var kimggroup = initNormalImage(img);
}
layer.add(kimggroup);
stage.add(layer);
// Draw the img
stage.draw();
}
/*
* Add background image
*/
function initBackgroundImage(img) {
var img = prepareBackground(img);
stage.setSize(img.width, img.height);
var kimggroup = new Kinetic.Group({
x: 0,
y: 0,
draggable: false
});
// Make the img and add it to the group
var kimg = new Kinetic.Image({
x: 0,
y: 0,
image: img,
width: img.width,
height: img.height,
name: "image"
});
kimggroup.add(kimg);
return kimggroup;
}
/*
* Add normal image
*/
function initNormalImage(img) {
var kimggroup = new Kinetic.Group({
x: stage.attrs.width / 2,
y: stage.attrs.height / 2,
draggable: true,
centerOffset: [img.width / 2, img.height / 2]
});
// Make the img and add it to the group
var kimg = new Kinetic.Image({
x: 0,
y: 0,
image: img,
width: img.width,
height: img.height,
name: "image"
});
kimggroup.add(kimg);
// Add anchors for resizing and rotation
addAnchor(kimggroup, 0, 0, "tl");
addAnchor(kimggroup, img.width, 0, "tr");
addAnchor(kimggroup, img.width, img.height, "br");
addAnchor(kimggroup, 0, img.height, "bl");
addAnchor(kimggroup, img.width / 2, -20, "handle");
addAnchor(kimggroup, img.width / 2, -20, "ghost");
addAnchor(kimggroup, img.width / 2, img.height + 20, "flip");
// On click make the image selected
kimggroup.on("mousedown", function () {
wasSelected = selected;
selected = this;
updateSelected();
this.moveToTop();
stage.draw();
});
kimg.on("mouseover", function () {
document.body.style.cursor = "move";
});
kimg.on("mouseout", function () {
document.body.style.cursor = "default";
});
// Double click to remove
kimg.on("dblclick dbltap", function () {
layer.remove(kimggroup);
layer.draw();
});
return kimggroup;
}
/*
* Create anchor and add to group
*/
function addAnchor(group, x, y, name) {
var config = {
x: x,
y: y,
stroke: "#666",
fill: "#ddd",
strokeWidth: 2,
radius: 4,
name: name,
draggable: true
}
switch (name) {
case "handle":
config.draggable = false;
var anchor = addRotateAnchor(group, config);
break;
case "ghost":
config.stroke = "#666";
var anchor = addRotateGhostAnchor(group, config);
break;
case "flip":
config.stroke = "#666";
config.draggable = false;
var anchor = addFlipAnchor(group, config);
break;
default:
var anchor = addResizeAnchor(group, config);
break;
}
anchor.hide();
group.add(anchor);
}
/*
* Set up resize anchor
*/
function addResizeAnchor(group, config) {
var anchor = new Kinetic.Circle(config);
anchor.on("dragmove", function () {
resize(group, this);
layer.draw();
});
anchor.on("mousedown touchstart", function () {
group.draggable(false);
this.moveToTop();
});
anchor.on("dragend", function () {
fixCenterOffset(group);
group.draggable(true);
layer.draw();
});
anchor.on("mouseover", function () {
var layer = this.getLayer();
document.body.style.cursor = "pointer";
this.setStrokeWidth(3);
layer.draw();
});
anchor.on("mouseout", function () {
var layer = this.getLayer();
document.body.style.cursor = "default";
this.setStrokeWidth(2);
layer.draw();
});
return anchor;
}
/*
* Set up rotation anchor
*/
function addRotateAnchor(group, config) {
var anchor = new Kinetic.Circle(config);
anchor.on("mouseover", function () {
var layer = this.getLayer();
document.body.style.cursor = "pointer";
this.setStrokeWidth(3);
layer.draw();
});
anchor.on("mouseout", function () {
var layer = this.getLayer();
document.body.style.cursor = "default";
this.setStrokeWidth(2);
layer.draw();
});
return anchor;
}
/*
* Set up rotation ghost anchor
*/
function addRotateGhostAnchor(group, config) {
var anchor = new Kinetic.Circle(config);
anchor.on("dragmove", function () {
rotate(group);
layer.draw();
});
anchor.on("mousedown touchstart", function () {
group.draggable(false);
this.moveToTop();
});
anchor.on("dragend", function () {
var handle = group.get(".handle")[0];
this.setPosition(handle.getPosition());
group.draggable(true);
layer.draw();
});
anchor.on("mouseover", function () {
var layer = this.getLayer();
document.body.style.cursor = "pointer";
this.setStrokeWidth(3);
layer.draw();
});
anchor.on("mouseout", function () {
var layer = this.getLayer();
document.body.style.cursor = "default";
this.setStrokeWidth(2);
layer.draw();
});
return anchor;
}
/*
* Set up flip anchor
*/
function addFlipAnchor(group, config) {
var anchor = new Kinetic.Circle(config);
anchor.on("mousedown touchstart", function () {
flip(group);
layer.draw();
});
anchor.on("mouseover", function () {
var layer = this.getLayer();
document.body.style.cursor = "pointer";
this.setStrokeWidth(3);
layer.draw();
});
anchor.on("mouseout", function () {
var layer = this.getLayer();
document.body.style.cursor = "default";
this.setStrokeWidth(2);
layer.draw();
});
return anchor;
}
/*
* Show anchors only when group selected
*/
function updateSelected() {
// Deselect the old img if there was any
if (wasSelected) {
wasSelected.get(".tl")[0].hide();
wasSelected.get(".tr")[0].hide();
wasSelected.get(".br")[0].hide();
wasSelected.get(".bl")[0].hide();
wasSelected.get(".handle")[0].hide();
wasSelected.get(".ghost")[0].hide();
wasSelected.get(".flip")[0].hide();
}
// Select the new image
selected.get(".tl")[0].show();
selected.get(".tr")[0].show();
selected.get(".br")[0].show();
selected.get(".bl")[0].show();
selected.get(".handle")[0].show();
selected.get(".ghost")[0].show();
selected.get(".flip")[0].show();
}
/*
* Add clicked images to the canvas
*/
function addClickedImage(name) {
var img = document.getElementById(name);
initImage(img, "normal");
}
/*
* Listen for images dragged into canvas and add them
*/
function setupDragAndDrop() {
stage.content.addEventListener("dragover", function (evt) {
evt.preventDefault();
}, false);
// Handle dropped image file - only Firefox and Google Chrome
stage.content.addEventListener("drop", function (evt) {
dragImg = new Image();
var files = evt.dataTransfer.files;
if (files.length > 0) {
var file = files[0];
if (typeof FileReader !== "undefined" && file.type.indexOf("image") != -1) {
var reader = new FileReader();
reader.onload = function (evt) {
dragImg.src = evt.target.result;
};
reader.readAsDataURL(file);
dragImg.onload = function () {
if (!haveBackground) {
haveBackground = true;
var type = "background";
} else {
var type = "normal";
}
initImage(this, type);
}
}
}
evt.preventDefault();
}, false);
}
window.onload = function () {
initCanvas("container");
setupDragAndDrop();
};
</script>
答案 0 :(得分：1)
更多详情：
由于您无法“删除未定义的子项”，因此您的图层未在某处定义（或被删除或覆盖）。
确保你有这个地方：
var layer = new Kinetic.Layer();
无法访问儿童对于您的舞台来说意味着相同。但是简单地说因为'kinetic'没有在某个地方被定义，你要么在你的来源中不包括Kinetic.4.3.0.1.JS，要么你的声明不正确。
确保您在某处引用了kinetic.js文件，例如或者标记：
<script src='http://d3lp1msu2r81bx.cloudfront.net/kjs/js/lib/kinetic-v4.3.1.js'></script>
或链接到项目中的硬拷贝
<script src='../kinetic-v4.3.1.js'></script> // in this example it is located one directory up, but you could put it anywhere really.
答案 1 :(得分：1)
这是范围问题。
无法从函数clearCanvas（）访问您的变量图层。 不理想，但它首先定义变量，然后像以下一样使用它;
<script>
var layer;
$( function() {
layer = new Kinetic.Layer();
.....
});
</script>
同样适用于你的变量'stage'
---在评论后编辑---
<script>
var layer, script, stage;
function initCanvas(id) {
stage = new Kinetic.Stage({ container: id, width: 150, height: 50 });
layer = new Kinetic.Layer();
stage.add(layer);
stage.draw();
}
</script>
如果你在函数中定义'stage = something'，它的工作方式就像'var stage = something'。 所以如果你想访问函数之外的stage和layer，你可以在函数之外定义它。