I am making an application in which user can drag & drop multiple objects from a toolbar onto a canvas.After dragging and dropping that particular object onto the canvas the user can move that object around in the canvas.Double Clicking on that object will make it disappear.I have been able to implement this for one object in the toolbar as shown in the link below..
http://jsfiddle.net/gkefk/26/
To drag & drop multiple objects from the toolbar I made the following additions in the function DragDrop()
var image2 = new Kinetic.Image({
name: data,
id: "image"+(imageCount++),
x: x,
y: y,
image2: theImage2,
draggable: true
});
image2.on('dblclick', function() {
image2.remove();
layer.draw();
});
layer.add(image2);
layer.draw();
var image3 = new Kinetic.Image({
name: data,
id: "image"+(imageCount++),
x: x,
y: y,
image3: theImage3,
draggable: true
});
image3.on('dblclick', function() {
image3.remove();
layer.draw();
});
layer.add(image3);
layer.draw();
The Fiddle containing the above code is http://jsfiddle.net/gkefk/29/
Even though I've made the necessary additions in the DragDrop() function, the two new objects are visible in the toolbar but i'm not being able to drag,drop,move around and delete them like the first object.Please Help...
I made it work with some major changes:
The image sources are provided in a dynamic array - so you can extend this at one single place in your code:
var imageSrc = [
"http://t2.gstatic.com/images?q=tbn:ANd9GcQ5fOr5ro_dK6D9UmSsVn0Z9m1QQMqRwr0z1tP_BzEGr7GuTrgeZQ",
"http://sandbox.kendsnyder.com/IM/square-stripped.png",
"http://t3.gstatic.com/images?q=tbn:ANd9GcRBYkAv40Eeaxlze2dqhayvKUeoUH6l_jYNLlsfjzJu0Uy9ucjcNA"
];
(of course you also have to update your HTML with the toolbar accordingly)
The list of images gets processed in a loop and for each element a new draggable object is created in connection with the corresponding <img id = "..." />:
//loop through imageSrc list
for (var i = 0; i < imageSrc.length; i++) {
//use a closure to keep references clean
(function() {
var $house, image;
var $house = $("#house"+i);
$house.hide();
image = new Image();
image.onload = function () {
$house.show();
}
image.src = imageSrc[i];
// start loading the image used in the draggable toolbar element
// this image will be used in a new Kinetic.Image
// make the toolbar image draggable
$house.draggable({helper: 'clone'});
$house.data("url", "house.png"); // key-value pair
$house.data("width", "32"); // key-value pair
$house.data("height", "33"); // key-value pair
$house.data("image", image); // key-value pair
})();
}
The counter for IDs is only relevant to the new element that is created on drop. As you only drop one image at the same time you also have to create a single new Image() only, instead of trying to create three of them.
Your working example can be found here and is extensible: http://jsfiddle.net/gkefk/32/
Related
i'm working on this graphic visualizer. following is a example code of what i'm doing.
first i create new canvas and there is a simple jQuery click event to add image objects to canvas.and after working on this canvas i need to load data from database, I've managed to save data on database by "Serialization" which default support by fabric-js. and retrieve data as a json object to load in to canvas. what i want is to completely remove current working canvas and load a new with database retrieved data. so here what i've done so far...
(function() {
var canvasOffsetHeight = '400';
var canvasOffsetWidth = '600';
var canvas = new fabric.Canvas('canvas');
window.addEventListener('resize', resizeCanvas, false);
function resizeCanvas() {
canvas.setHeight(canvasOffsetHeight);
canvas.setWidth(canvasOffsetWidth);
canvas.renderAll();
}
// resize on init
resizeCanvas();
jQuery('.category ul').on('click', 'li', function (e) {
var imgElement = jQuery(this).children("img")[0];
var imgInstance = new fabric.Image(imgElement, {
left: 100,
top: 100,
angle: 0,
opacity: 1
});
canvas.add(imgInstance);
canvas.renderAll();
return false;
});
jQuery('#obj').click(function(){
canvas_data = '{"objects":[{"type":"rect","left":50,"top":50,"width":20,"height":20,"fill":"green","overlayFill":null,"stroke":null,"strokeWidth":1,"strokeDashArray":null,"scaleX":1,"scaleY":1,"angle":0,"flipX":false,"flipY":false,"opacity":1,"selectable":true,"hasControls":true,"hasBorders":true,"hasRotatingPoint":false,"transparentCorners":true,"perPixelTargetFind":false,"rx":0,"ry":0}],"background":"rgba(0, 0, 0, 0)"}';
var canvas = new fabric.Canvas('canvas');
canvas.loadFromJSON(canvas_data,canvas.renderAll.bind(canvas));
});
})();
here lets assume "canvas_data" is the data from database.
the problem is when i load data from an object it appears on canvas correctly but soon as i click on them they just vanishing.
i think because main function run onLoad so when i click it triggers the main function and load the previous canvas. what i want is to wipe out old canvas and load new one with database data. please help.
they say "loadFromJSON" automatically does this for us but it seems not working for me.
No need to create another canvas object. So your code in the #obj.click becomes:
jQuery('#obj').click(function(){
canvas_data = '{"objects":[{"type":"rect","left":50,"top":50,"width":20,"height":20,"fill":"green","overlayFill":null,"stroke":null,"strokeWidth":1,"strokeDashArray":null,"scaleX":1,"scaleY":1,"angle":0,"flipX":false,"flipY":false,"opacity":1,"selectable":true,"hasControls":true,"hasBorders":true,"hasRotatingPoint":false,"transparentCorners":true,"perPixelTargetFind":false,"rx":0,"ry":0}],"background":"rgba(0, 0, 0, 0)"}';
canvas.loadFromJSON(canvas_data,canvas.renderAll.bind(canvas));
});
I'm working on a simple diagram editor using KineticJS. I would like to use two separate canvases for the palette area (that contains a number of Kinetic.Groups that represent the different nodes of the network I might create), and the diagramming area where I can add nodes from the palette via drag and drop, and then add connections between the various nodes as specific anchor points. I'm having trouble figuring out the drag and drop process from the palette canvas of (stationary) Kinetic.Groups over to the other canvas containing diagramming area. I'm guessing that I need to fire off of the dragstart event for the palette objects (although I don't want these themselves to be draggable), and then do something like create an opague copy of the palette object that can be dragged around, and finally dropped into the diagramming area (with full opacity).
Can groups be dragged outside of a the staging canvases boundaries? Maybe I need to generate an image when I start to drag from the palette, drag that image over, and then create another group when dropping into the diagramming area.
Does any one know of any examples that might point me in the right direction, or who can offer some insight (even code) into the required process. I've searched the KineticJS examples but can't quite find enough to get me going.
Here’s one way to drag nodes from a source palette into a destination group:
A Fiddle: http://jsfiddle.net/m1erickson/xtVyL/
Network nodes are represented by small icons (which are really small kinetic image objects).
The user can drag any icon from the source palette to any destination group.
The groups are just defined areas on the canvas, but could be Kinetc.Groups for more flexibility.
During the dragend event, a new duplicate copy of the dragged icon is created in the destination group.
After the dragend event is complete, the original palette icon is automatically moved from
The newly created duplicate icon can be dragged around the destination group (but not outside that group).
Here is code and a Fiddle: http://jsfiddle.net/m1erickson/xtVyL/
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Prototype</title>
<script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
<script src="http://d3lp1msu2r81bx.cloudfront.net/kjs/js/lib/kinetic-v4.5.5.min.js"></script>
<style>
#container{
border:solid 1px #ccc;
margin-top: 10px;
width:350px;
height:350px;
}
</style>
<script>
$(function(){
var stage = new Kinetic.Stage({
container: 'container',
width: 350,
height: 350
});
var layer = new Kinetic.Layer();
stage.add(layer);
// image loader
var imageURLs=[];
var imagesOK=0;
var imgs=[];
imageURLs.push("https://dl.dropboxusercontent.com/u/139992952/stackoverflow/tempPC.png");
imageURLs.push("https://dl.dropboxusercontent.com/u/139992952/stackoverflow/tempServer.png");
imageURLs.push("https://dl.dropboxusercontent.com/u/139992952/stackoverflow/tempRouter.png");
loadAllImages();
function loadAllImages(callback){
for (var i = 0; i < imageURLs.length; i++) {
var img = new Image();
imgs.push(img);
img.onload = function(){
imagesOK++;
if (imagesOK==imageURLs.length ) {
start();
}
};
img.src = imageURLs[i];
}
}
// top icon positions
var nextIconX=20;
var nextIconY=20;
// define groups
var groups=[];
groups.push({x:0,y:100,w:175,h:250,fill:"skyblue"});
groups.push({x:175,y:100,w:175,h:250,fill:"cornsilk"});
// add boundary info to each group
// draw colored rect to show group area
for(var i=0;i<groups.length;i++){
var g=groups[i];
g.left=g.x;
g.right=g.x+g.w;
g.top=g.y;
g.bottom=g.y+g.h;
var rect=new Kinetic.Rect({
x:g.x,
y:g.y,
width:g.w,
height:g.h,
fill:g.fill,
stroke:"gray"
});
layer.add(rect);
}
// hittest for each group
function groupHit(x,y){
for(var i=0;i<groups.length;i++){
var g=groups[i];
if(x>g.left && x<g.right && y>g.top && y<g.bottom){return(i);}
}
return(-1);
}
function start(){
makePaletteIcon(imgs[0]);
makePaletteIcon(imgs[1]);
makePaletteIcon(imgs[2]);
layer.draw();
}
function makePaletteIcon(img){
// make an icon that stays in the pallette tray
var fixedIcon=newImage(nextIconX,nextIconY,img,false);
layer.add(fixedIcon);
// make an icon that is dragged from the tray to a group
var dragIcon=makeDraggableIcon(nextIconX,nextIconY,img);
layer.add(dragIcon);
// calc the next icon position
nextIconX+=(img.width+20);
}
function makeDraggableIcon(x,y,img){
var i=newImage(x,y,img,true);
//
i.trayX=x;
i.trayY=y;
//
i.setOpacity(0.50);
i.on("dragend",function(){
var x=this.getX();
var y=this.getY();
// if this pallette icon was not dropped in a group
// put the icon back in the tray and return
var hit=groupHit(x,y);
if(hit==-1){
this.setPosition(this.trayX,this.trayY);
return;
}
// add a copy of this icon to the drop group
var component=newImage(x,y,this.getImage(),true);
// set drag limits
var group=groups[hit];
component.maxDragLeft=group.left;
component.maxDragRight=group.right;
component.maxDragTop=group.top;
component.maxDragBottom=group.bottom;
// limit component dragging to inside the assigned group
component.setDragBoundFunc(function(pos) {
var xx=pos.x;
var yy=pos.y;
var w=this.getWidth();
var h=this.getHeight();
if(pos.x<this.maxDragLeft){xx=this.maxDragLeft;}
if(pos.x+w>this.maxDragRight){xx=this.maxDragRight-w;}
if(pos.y<this.maxDragTop){yy=this.maxDragTop;}
if(pos.y+h>this.maxDragBottom){yy=this.maxDragBottom-h;}
return{ x:xx, y:yy };
});
layer.add(component);
// move the dragIcon back into the pallette tray
this.setPosition(this.trayX,this.trayY);
layer.draw();
});
return(i);
}
// make a new Kinetic.Image
function newImage(x,y,img,isDraggable){
var i=new Kinetic.Image({
image:img,
x: x,
y: y,
width: img.width,
height: img.height,
draggable:isDraggable
});
return(i);
}
}); // end $(function(){});
</script>
</head>
<body>
<p>Drag any icon from top into blue or yellow group</p>
<div id="container"></div>
</body>
</html>
I want to save part of a KineticJS stage. This code is working perfect:
stage.toDataURL({
width: 350,
height: 350,
mimeType: "image/jpeg",
callback: function(dataUrl) {
/*
* here you can do anything you like with the data url.
* In this tutorial we'll just open the url with the browser
* so that you can see the result as an image
*/
window.open(dataUrl);
}
});
}, false);
But what i want is to add an offset to that, so image would start and coordinates (75,75) of the stage area. Any idea?
Well, since there is no crop() method you would have to revert to moving all the objects on your stage 75 in both directions, luckily, this is not very difficult.
Something like:
var layersList = stage.getChildren();
for (var layerNum in layersList){ //loop through all layers
var childList = layerList.getChildren(); //get all children of the layer
for(var childNum in childList){
childList[childNum].move(-75,-75);
}
}
stage.draw();
stage.toDataURL({.....});
You can undo this by using the same code and doing .move(75,75); to place each item back in their original position
or if you want an offset defined through a function just do this:
function moveStage(offsetX, offsetY){
var layersList = stage.getChildren();
for (var layerNum in layersList){ //loop through all layers
var childList = layerList.getChildren(); //get all children of the layer
for(var childNum in childList){
childList[childNum].move(-offsetX,-offsetY);
}
}
stage.draw();
stage.toDataURL({.....});
}
I'm trying to build a transform manager for KineticJS that would build a bounding box and allow users to scale, move, and rotate an image on their canvas. I'm getting tripped up with the logic for the anchor points.
http://jsfiddle.net/mharrisn/whK2M/
I just want to allow a user to scale their image proportionally from any corner, and also rotate as the hold-drag an anchor point.
Can anyone help point me in the right direction?
Thank you!
Here is a proof of concept of a rotational control I've made:
http://codepen.io/ArtemGr/pen/ociAD
While the control is dragged around, the dragBoundFunc is used to rotate the content alongside it:
controlGroup.setDragBoundFunc (function (pos) {
var groupPos = group.getPosition()
var rotation = degrees (angle (groupPos.x, groupPos.y, pos.x, pos.y))
status.setText ('x: ' + pos.x + '; y: ' + pos.y + '; rotation: ' + rotation); layer.draw()
group.setRotationDeg (rotation); layer.draw()
return pos
})
I am doing the same thing, and I've posted a question which is allmoast the same, but I found a link where you have the resize and move tool ready developed. So I have used the same. It does not contain the rotate tool however, but this can be a good start for you too, it is very simple and logical. Here is the link: http://www.html5canvastutorials.com/labs/html5-canvas-drag-and-drop-resize-and-invert-images/
I will come back with the rotation tool as well if I manage to get it working perfectly.
I hope I am not late yet for posting this code snippet that I made. I had the same problem with you guys dealing with this kind of task. Its been 3 days since I tried so many workarounds to mimic the fabricjs framework capability when dealing with images and objects. I could use Fabricjs though but it seems that Kineticjs is more faster/consistent to deal with html5.
Luckily, we already have existing plugin/tool that we could easily implement together with kineticjs and this is jQuery Transform tool. SUPER THANKS TO THE AUTHOR OF THIS! Just search this on google and download it.
I hope the code below that I created would help lots of developers out there who is pulling their hair off to solve this kind of assignment.
$(function() {
//Declare components STAGE, LAYER and TEXT
var _stage = null;
var _layer = null;
var simpleText = null;
_stage = new Kinetic.Stage({
container: 'canvas',
width: 640,
height: 480
});
_layer = new Kinetic.Layer();
simpleText = new Kinetic.Text({
x: 60,
y: 55,
text: 'Simple Text',
fontSize: 30,
fontFamily: 'Calbiri',
draggable: false,
name:'objectInCanvas',
id:'objectCanvas',
fill: 'green'
});
//ADD LAYER AND TEXT ON STAGE
_layer.add(simpleText);
_stage.add(_layer);
_stage.draw();
//Add onclick event listener to the Stage to remove and add transform tool to the object
_stage.on('click', function(evt) {
//Remove all objects' transform tool inside the stage
removeTransformToolSelection();
// get the shape that was clicked on
ishape = evt.targetNode;
//Add and show again the transform tool to the selected object and update the stage layer
$(ishape).transformTool('show');
ishape.getParent().moveToTop();
_layer.draw();
});
function removeTransformToolSelection(){
//Search all objects inside the stage or layer who has the name of "objectInCanvas" using jQuery iterator and hide the transform tool.
$.each(_stage.find('.objectInCanvas'), function( i, child ) {
$(child).transformTool('hide');
});
}
//Event listener/Callback when selecting image using file upload element
function handleFileSelect(evt) {
//Remove all objects' transform tool inside the stage
removeTransformToolSelection();
//Create image object for selected file
var imageObj = new Image();
imageObj.onload = function() {
var myImage = new Kinetic.Image({
x: 0,
y: 0,
image: imageObj,
name:'objectInCanvas',
draggable:false,
id:'id_'
});
//Add to layer and add transform tool
_layer.add(myImage);
$(myImage).transformTool();
_layer.draw();
}
//Adding source to Image object.
var f = document.getElementById('files').files[0];
var name = f.name;
var url = window.URL;
var src = url.createObjectURL(f);
imageObj.src = src;
}
//Attach event listener to FILE element
document.getElementById('files').addEventListener('change', handleFileSelect, false);
});
Creating a new object on mouseclick as a way for users to create reference points (which I call 'crumbs') when reading large web documents. I've got this working with a new Image() function, however, that won't let me assign a tabindex to each new image created by mouseclick (posX, posY). 'crumbtoggle' simply acknowledges that the crumb dropping tool has been selected.
working new Image() function:
function draw_crumb()
{
var b_canvas = document.getElementById("b");
var b_context = b_canvas.getContext("2d");
var crumb = new Image();
crumb.src = "crumb.gif";
if(crumbtoggle.className == "on")
{
b_context.drawImage(crumb, posX-20, posY-20, 50, 75);
}
}
non-working new Object () function:
function draw_crumb()
{
var b_canvas = document.getElementById("b");
var b_context = b_canvas.getContext("2d");
var crumb = new Object();
crumb.type = "button";
crumb.src = "crumb.gif";
crumb.tabindex = 1;
if(crumbtoggle.className == "on")
{
b_context.drawObject(crumb, posX-20, posY-20, 50, 75);
}
}
I've looked in to applying focus to the new Image objects, but that doesn't seem to be a good alternative to tabindex attributes. Any ideas would be greatly appreciated.
An HTML5 Canvas is like a real-world canvas with instantly-drying paint. When you paint a rectangle or line or image on the canvas, it becomes part of the canvas. You cannot later re-order the items, or move them relative to each other. It is not a separate entity that can get focus.
Any sort of focus management integrated with the browser's handling of focus will have to be done through form inputs or anchors recognized by the browser.
It's not clear to me why you need a canvas, or if you need one at all.