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How can i keep the Konvas layer centered after resize?

So i'm using Konvajs, to draw segments, only vertical and horizontal. My problem is the following, when i start the debug, if the window is small and then i click to maximize, the layer will stay with same size as when small. Ex:
here it s the Javascript file for the Konva creation:
function setUpDesignMap(){
var width = $('#designContainer').width();
var height = $('#designContainer').height();
var blockSnapSize = gridSize;
var isDrawing = false;
var drawShape = null;
designStage = new Konva.Stage({
container: 'designContainer',
width: width,
height: height,
draggable: true,
name:'designStage'
// dragBoundFunc: function(pos) {
// var newY = pos.y < 0 ? 0 : pos.y;
// var newX = pos.x < 0 ? 0 : pos.x;
// return {
// x: newX,
// y: newY
// };
// }
});
/*Set up grid*/
var gridLayer = new Konva.Layer();
var tipLayer = new Konva.Layer();
drawLayer = new Konva.Layer();
segGrp = new Konva.Group({name:'segments'});
/* draw grid */
for (var i = 0; i < 240; i++) {
gridLayer.add(new Konva.Line({
points: [Math.round(i * blockSnapSize), 0, Math.round(i * blockSnapSize), 120*blockSnapSize],
stroke: '#888',
strokeWidth: 0.5,
}));
}
gridLayer.add(new Konva.Line({points: [0,0,10,10]}));
for (var j = 0; j < 120; j++) {
gridLayer.add(new Konva.Line({
points: [0, Math.round(j * blockSnapSize), 240*blockSnapSize, Math.round(j * blockSnapSize)],
stroke: '#888',
strokeWidth: 0.5,
}));
}
/* Stage initial position*/
zoomVars_design = {scale: 1, factor: 1.1, origin: {x:-100*gridSize,y:-50*gridSize}};
designStage.position(zoomVars_design.origin);
designStage.scale({ x: 1, y: 1 });
/*Set up mouse tip*/
var mouseTip = new Konva.Rect({
width: 6,
height: 6,
opacity:0,
fill: '#FFCC00',
stroke: '#FFCC00'
});
tipLayer.add(mouseTip);
/* Set up length indicator */
var lenShape = new Konva.Line({
points:[],
opacity: 1,
strokeWidth: 1,
stroke: '#000',
dash:[7,5]
});
gridLayer.add(lenShape);
/* Set up length text*/
var lenText = new Konva.Text({
align: 'center',
verticalAlign: 'middle',
fontSize: 12
});
gridLayer.add(lenText);
var lenSide = new Konva.Line({
points:[],
opacity: 1,
strokeWidth: 1,
stroke: '#000',
dash:[7,5]
});
gridLayer.add(lenSide);
/*Mouse handlers*/
//remove default behaviour for the container
$("#designContainer").on('mousedown', function(e){
e.preventDefault();
});
$("#designContainer").on('contextmenu', function(e){
e.preventDefault();
});
//mouse handlers on stage
designStage.on('contentMousedown', function (e) {
if(e.evt.button == 0){
designStage.draggable(false);
}
else{
designStage.draggable(true);
return;
}
if(mouseMode == 0){ //draw mode
var startPoint = {x:(mouseTip.attrs.x+3), y:(mouseTip.attrs.y+3)};
if(!isDrawing){
if(!isIntersection(startPoint)){ //cannot be intersection to avoid crosses
//check if there's an intersection on the begining
if(isCorner(startPoint)){
intersectingSeg = false;
intersectingCorner = true;
console.log('intersectingSeg = false')
}
else{
//check if its on an existing segment
var isonseg = isOnSegment(startPoint);
if(isonseg.b){
//validate resulting segments length
var intercected = getSegmentsArray(isonseg.d)[isonseg.i];
var res = breakSegAtIntersection(startPoint,intercected);
if(isValidLength(res[0].start,res[0].end) && isValidLength(res[1].start,res[1].end)){
intersectingSeg = true;
intersectingCorner = false;
console.log('>>>>>>>Intersecting Segment at start')
}
else{
consoleAdd('Resulting segments are too small to you');
return;
}
}
}
//start drawing
drawShape = new Konva.Line({
points: [startPoint.x, startPoint.y],
strokeWidth: 15,
stroke: 'black',
opacity: 0.5,
dir:'h'
});
drawShape.on('mouseover', function (e) {
if(mouseMode == 1){
this.stroke('#031C4D');
drawLayer.draw();
}
});
drawShape.on('mouseout', function (e) {
if(mouseMode == 1){
this.stroke('black');
drawLayer.draw();
}
});
drawShape.on('mouseup', function (e) {
if(mouseMode == 1){
this.stroke('#092C70');
drawLayer.draw();
}
});
segGrp.add(drawShape);
drawLayer.add(segGrp);
drawLayer.draw();
isDrawing = true;
}
else{
consoleAdd('Cannot start on an intersection');
}
gridLayer.draw();
}
}
});
So i want the layer not to be that small, always refitting. Thank you all for your attention!

You need to manually resize your stage when the size of container element is changed.
window.addEventListener('resize', () => {
var width = $('#designContainer').width();
var height = $('#designContainer').height();
designStage.width(width);
designStage.height(height);
})
You may also need to apply the scale to the stage.
Take a look into related demo: https://konvajs.org/docs/sandbox/Responsive_Canvas.html

Fabric JS : I need to delete an quadratic curved arrow tool after once created on canvas

I am trying to make a quadratic curved arrow tool.
I was used demo in the following link for creating the tool.
http://kpomservices.com/oldweb/HTML5_Canvas_Curved_Lines.php
i was success to create an tool as I needs.
but I am getting some issues with that.
Hope someone here can help me on that issues...
here is the code I am using for creating the tool ..
line_number++;
var line;
var reinit_stroke = "";
fabric.Object.prototype.originX = fabric.Object.prototype.originY = 'center';
function _getQBezierValue(t, p1, p2, p3) {
var iT = 1 - t;
return iT * iT * p1 + 2 * iT * t * p2 + t * t * p3;
}
function getQuadraticCurvePoint(startX, startY, cpX, cpY, endX, endY, position) {
return {
x: _getQBezierValue(position, startX, cpX, endX),
y: _getQBezierValue(position, startY, cpY, endY)
};
}
canvas.on({
'object:selected': onObjectSelected,
'object:moving': onObjectMoving,
'before:selection:cleared': onBeforeSelectionCleared
});
(function drawQuadratic() {
line = new fabric.Path('M 65 0 Q 100, 100, 200, 0', { fill: '', selectable: false,hasBorders: false,hasControls: false,stroke: #000});
line.path[0][1] = posx;
line.path[0][2] = posy;
line.path[1][1] = posx+50;
line.path[1][2] = posy+50;
line.path[1][3] = posx+100;
line.path[1][4] = posy+100;
line.id = line_number;
//line.selectable = false;
canvas.add(line);
canvas.sendBackwards(line);
var pt = getQuadraticCurvePoint(line.path[0][1], line.path[0][2], line.path[1][1], line.path[1][2], line.path[1][3], line.path[1][4], 0.5);
var p1 = makeCurvePoint(pt.x, pt.y, null, line, null)
p1.name = "p1";
p1.id = line_number;
canvas.add(p1);
var p0 = makeCurveCircle(posx, posy, line, p1, null);
p0.name = "p0";
p0.id = line_number;
canvas.add(p0);
var p2 = makeArrow(posx+100, posy+100, null, p1, line);
p2.name = "p2";
p2.id = line_number;
canvas.add(p2);
var dx = line.path[1][3] - posx;
var dy = line.path[1][4] - posy;
var angle = Math.atan2(dy, dx) * 180 / Math.PI;
p2.setAngle(angle + 90);
p2.setCoords();
canvas.bringToFront(p2);
canvas.bringToFront(p0);
canvas.bringToFront(p1);
line.p2 = p2;
})();
function makeArrow(left, top, line1, line2, line3) {
var c = new fabric.Triangle({
width: 5,
height: 5,
left: left+5,
top: top+5,
strokeWidth: 10,
fill: #000,
opacity: 1,
stroke: #000
});
c.hasBorders = c.hasControls = false;
c.angle = 90;
c.line1 = line1;
c.line2 = line2;
c.line3 = line3;
return c;
}
function makeCurveCircle(left, top, line1, line2, line3) {
var c = new fabric.Circle({
radius: 5,
left: left,
top: top,
strokeWidth: 10,
fill: #000,
stroke: #000
});
c.hasBorders = c.hasControls = false;
c.line1 = line1;
c.line2 = line2;
c.line3 = line3;
return c;
}
function makeCurvePoint(left, top, line1, line2, line3) {
var c = new fabric.Circle({
radius: 5,
left: left,
top: top,
strokeWidth: 10,
fill: #000,
opacity: 0,
stroke: #000
});
c.hasBorders = c.hasControls = false;
c.angle = 90;
c.line1 = line1;
c.line2 = line2;
c.line3 = line3;
return c;
}
var prevselobj;
function onObjectSelected(e) {
var activeObject = e.target;
reinit_stroke = activeObject.stroke;
if (activeObject.name == "p0" || activeObject.name == "p2") {
if (prevselobj) {
prevselobj.line2.animate('opacity', '0', {
duration: 200,
onChange: canvas.renderAll.bind(canvas),
});
prevselobj.line2.selectable = false;
}
activeObject.line2.animate('opacity', '1', {
duration: 200,
onChange: canvas.renderAll.bind(canvas),
});
activeObject.line2.selectable = true;
prevselobj = activeObject;
}
}
function onBeforeSelectionCleared(e) {
var activeObject = e.target;
if (activeObject.name == "p0" || activeObject.name == "p2") {
activeObject.line2.animate('opacity', '0', {
duration: 200,
onChange: canvas.renderAll.bind(canvas),
});
activeObject.line2.selectable = false;
}
else if (activeObject.name == "p1") {
activeObject.animate('opacity', '0', {
duration: 200,
onChange: canvas.renderAll.bind(canvas),
});
activeObject.selectable = true;
}
}
function onObjectMoving(e) {
if (e.target.name == "p0" || e.target.name == "p2") {
var p = e.target;
var curvedline;
if (p.line1) {
p.line1.path[0][1] = p.left;
p.line1.path[0][2] = p.top + p.height/2;
curvedline = p.line1;
} else if (p.line3) {
p.line3.path[1][3] = p.left;
if(p.line3.path[0][2] <= p.line3.path[1][4])
p.line3.path[1][4] = p.top - p.height/2;
if(p.line3.path[0][2] > p.line3.path[1][4])
p.line3.path[1][4] = p.top + p.height/2;
p.line3.setCoords();
curvedline = p.line3;
}
if (curvedline) {
curvedline.setCoords();
var pt = getQuadraticCurvePoint(curvedline.path[0][1], curvedline.path[0][2], curvedline.path[1][1], curvedline.path[1][2], curvedline.path[1][3], curvedline.path[1][4], 0.5);
p.line2.left = pt.x;
p.line2.top = pt.y;
if (curvedline.p2) {
var pt = getQuadraticCurvePoint(curvedline.path[0][1], curvedline.path[0][2], curvedline.path[1][1], curvedline.path[1][2], curvedline.path[1][3], curvedline.path[1][4], 0.99);
curvedline.p2.left = pt.x;
curvedline.p2.top = pt.y;
var dx = curvedline.path[1][3] - pt.x;
var dy = curvedline.path[1][4] - pt.y;
var angle = Math.atan2(dy, dx) * 180 / Math.PI;
curvedline.p2.setAngle(angle + 90);
curvedline.p2.setCoords();
}
p.line2.setCoords();
}
if (e.target.text) {
e.target.text.left = p.left;
e.target.text.top = p.top;
e.target.text.setCoords();
}
} else if (e.target.name == "p1") {
var p = e.target;
if (p.line2) {
p.line2.path[1][1] = p.left;
p.line2.path[1][2] = p.top;
}
curvedline = p.line2;
if (curvedline) {
var pt = getQuadraticCurvePoint(curvedline.path[0][1], curvedline.path[0][2], curvedline.path[1][1], curvedline.path[1][2], curvedline.path[1][3], curvedline.path[1][4], 0.5);
p.left = pt.x;
p.top = pt.y;
p.setCoords();
}
if (curvedline) {
var pt = getQuadraticCurvePoint(curvedline.path[0][1], curvedline.path[0][2], curvedline.path[1][1], curvedline.path[1][2], curvedline.path[1][3], curvedline.path[1][4], 0.99);
curvedline.p2.left = pt.x;
curvedline.p2.top = pt.y;
var dx = curvedline.path[1][3] - pt.x;
var dy = curvedline.path[1][4] - pt.y;
var angle = Math.atan2(dy, dx) * 180 / Math.PI;
curvedline.p2.setAngle(angle + 90);
curvedline.p2.setCoords();
}
} else if (e.target.name == "p0" || e.target.name == "p2") {
var p = e.target;
p.line1 && p.line1.set({
'x2': p.left,
'y2': p.top
});
p.line2 && p.line2.set({
'x1': p.left,
'y1': p.top
});
p.line3 && p.line3.set({
'x1': p.left,
'y1': p.top
});
p.line4 && p.line4.set({
'x1': p.left,
'y1': p.top
});
}
p && reinit();
}
function reinit() {
canvas.remove(line);
line = new fabric.Path(line.path, { fill: '',selectable: false });
line.id = line_number;
line.stroke = reinit_stroke;
canvas.add(line);
canvas.sendBackwards(line);
}
canvas.on('mouse:over', function(e) {
if(e.target.type == "path")
{
canvas.sendBackwards(e.target);
}
});
I am using following code for delete the tool.
(Note: this code runs when I click on the delete button.
Delete button deletes the object selected. )
here is the code...
var objs = canvas.getObjects();
if (activeObject) {
active_id = activeObject.get('id');
canvas.forEachObject(function (obj) {
if(obj.get('id') == active_id)
{
if(obj.type == 'path')
{
obj.selectable = true;
canvas.remove(obj);
}
canvas.remove(obj);
}
});
canvas.remove(activeObject);
}
the issue I am getting is after delete this, If I create one other curved arrow in the designer(i.e. without reload the page) and move the nodes then its still showing the old path object which we already deleted.
and If I delete the newly created curved arrow then it removes all path from canvas, In short all Path object behave like one(Hope this is understandable) .
so, the path object is not getting deleted properly it is just getting hidden when I am deleting it. Or may be it is deleted but created again when I am moving another path object..
and if we save the canvas as json then we can see the path objects which are deleted too.
What I need to do is to delete the path object properly and save just the Path object currently showing on the canvas with nodes.
Please tell me if there is some solution for this issues..
Thanks..

I found the solution for the delete curve Issue.
We need to change the code at the reinit() functions.
It was overwrite the line_id to all the line(or say path) in the canvas.
Here is the code to replace with reinit() function..
function reinit() {
var objs = canvas.getObjects();
current_line = canvas.getActiveObject();
canvas.forEachObject(function (obj) {
if(obj.type == 'path' && obj.get("id") == current_line.get("id"))
{
canvas.remove(obj);
line = new fabric.Path(obj.path, { fill: '',selectable: false });
line.id = current_line.get("id");
line.stroke = reinit_stroke;
canvas.add(line);
canvas.sendBackwards(line);
}
});
}
Hope this can be helpful for someone who need this kind of solution..

Fabric.js Sticky Note type text wrap

I am trying to make a sticky note type utility with the fabric canvas. It will help to be used as annotators.
I want the text to wrap by itself at the given rectangle's width.
Can someone update my fiddle work??
Suggestions are appreciated. Regards...
The following is the link to a part of my fiddle:
http://jsfiddle.net/U7E9q/5/
var canvas = new fabric.Canvas('fabric-canvas');
canvas.hoverCursor = 'pointer';
var text = new fabric.IText("Enter Text Here ",{
fontSize: 20,
top: 100,
left: 100,
backgroundColor: '#faa',
lockScalingX: true,
lockScalingY: true,
selectable: true
});
//alert(text.text);
var rect = new fabric.Rect({
text_field: text,
width: 200,
height: 50,
fill: '#faa',
rx: 10,
ry: 10,
top: 100,
left: 100
});
canvas.add(rect);
canvas.add(text);
canvas.on('object:moving', function (event){
canvas.renderAll();
});
createListenersKeyboard();
function createListenersKeyboard() {
document.onkeydown = onKeyDownHandler;
//document.onkeyup = onKeyUpHandler;
}
function onKeyDownHandler(event) {
//event.preventDefault();
var key;
if(window.event){
key = window.event.keyCode;
}
else{
key = event.keyCode;
}
switch(key){
//////////////
// Shortcuts
//////////////
// Copy (Ctrl+C)
case 67: // Ctrl+C
if(ableToShortcut()){
if(event.ctrlKey){
event.preventDefault();
copy();
}
}
break;
// Delete (Ctrl+D)
case 127: // Ctrl+D
if(ableToShortcut()){
if(event.deleteKey){
delet();
}
}
break;
// Paste (Ctrl+V)
case 86: // Ctrl+V
if(ableToShortcut()){
if(event.ctrlKey){
event.preventDefault();
paste();
}
}
break;
default:
// TODO
break;
}
}
function ableToShortcut(){
/*
TODO check all cases for this
if($("textarea").is(":focus")){
return false;
}
if($(":text").is(":focus")){
return false;
}
*/
return true;
}
function copy(){
if(canvas.getActiveGroup()){
for(var i in canvas.getActiveGroup().objects){
var object = fabric.util.object.clone(canvas.getActiveGroup().objects[i]);
object.set("top", object.top+5);
object.set("left", object.left+5);
copiedObjects[i] = object;
}
}
else if(canvas.getActiveObject()){
var object = fabric.util.object.clone(canvas.getActiveObject());
object.set("top", object.top+5);
object.set("left", object.left+5);
copiedObject = object;
copiedObjects = new Array();
}
}
function paste(){
if(copiedObjects.length > 0){
for(var i in copiedObjects){
canvas.add(copiedObjects[i]);
}
}
else if(copiedObject){
canvas.add(copiedObject);
}
canvas.renderAll();
}
function delet(){
var activeObject = canvas.getActiveObject();
canvas.remove(activeObject);
console.log('after remove getActiveObject(): ', canvas.getActiveObject(), activeObject === canvas.getActiveObject());
canvas.renderAll();
}

If you manage the sticky note as a grouped rect and text you can improve the same behavior. When you need to edit the text inside the group, you just ungroup and clone the elements, append the cloned elements to the canvas and set text as editable.
You need to handle an event like double click to handle this behavior and then handle the mousedown or other interactivity with canvas to regroup them.

http://jsfiddle.net/4HE3U/1/
Above is one fiddle that can satisfy you
Basically i have made one group of Text and Rectangle and i have added it to canvas. There is only one change you need to make is that you can take one textbox to get current sticky note text content as we can not edit text of i-text online once we are adding it any group. Currently there is no way for IText to handle the events as they are not handed down to it if it's contained in a group. I think this is also the prefered way to handle that as it would confuse the user - what if he starts to edit multiple texts. This might end up in a mess. Maybe you can rework your script a little to workaround this problems.
I have added Text and Rectangle
var canvas = new fabric.Canvas('fabric-canvas');
canvas.hoverCursor = 'pointer';
var text = new fabric.IText("Enter Text Here ",{
fontSize: 20,
top: 100,
left: 100,
backgroundColor: '#faa',
lockScalingX: true,
lockScalingY: true,
selectable: true
});
//alert(text.text);
var rect = new fabric.Rect({
text_field: text,
width: 200,
height: 50,
fill: '#faa',
rx: 10,
ry: 10,
top: 100,
left: 100
});
var group = new fabric.Group([ rect, text ], {
left: 100,
top: 100,
lockScalingX: true,
lockScalingY: true,
hasRotatingPoint: false,
transparentCorners: false,
cornerSize: 7
});
canvas.add(group);
//canvas.add(text);
canvas.on('object:moving', function (event){
canvas.renderAll();
});
createListenersKeyboard();
function createListenersKeyboard() {
document.onkeydown = onKeyDownHandler;
//document.onkeyup = onKeyUpHandler;
}
function onKeyDownHandler(event) {
//event.preventDefault();
var key;
if(window.event){
key = window.event.keyCode;
}
else{
key = event.keyCode;
}
switch(key){
//////////////
// Shortcuts
//////////////
// Copy (Ctrl+C)
case 67: // Ctrl+C
if(ableToShortcut()){
if(event.ctrlKey){
event.preventDefault();
copy();
}
}
break;
// Delete (Ctrl+D)
case 127: // Ctrl+D
if(ableToShortcut()){
if(event.deleteKey){
delet();
}
}
break;
// Paste (Ctrl+V)
case 86: // Ctrl+V
if(ableToShortcut()){
if(event.ctrlKey){
event.preventDefault();
paste();
}
}
break;
default:
// TODO
break;
}
}
function ableToShortcut(){
/*
TODO check all cases for this
if($("textarea").is(":focus")){
return false;
}
if($(":text").is(":focus")){
return false;
}
*/
return true;
}
function copy(){
if(canvas.getActiveGroup()){
for(var i in canvas.getActiveGroup().objects){
var object = fabric.util.object.clone(canvas.getActiveGroup().objects[i]);
object.set("top", object.top+5);
object.set("left", object.left+5);
copiedObjects[i] = object;
}
}
else if(canvas.getActiveObject()){
var object = fabric.util.object.clone(canvas.getActiveObject());
object.set("top", object.top+5);
object.set("left", object.left+5);
copiedObject = object;
copiedObjects = new Array();
}
}
function paste(){
if(copiedObjects.length > 0){
for(var i in copiedObjects){
canvas.add(copiedObjects[i]);
}
}
else if(copiedObject){
canvas.add(copiedObject);
}
canvas.renderAll();
}
function delet(){
var activeObject = canvas.getActiveObject();
canvas.remove(activeObject);
console.log('after remove getActiveObject(): ', canvas.getActiveObject(), activeObject === canvas.getActiveObject());
canvas.renderAll();
}
<canvas id="fabric-canvas" width="400" height="400"></canvas>

Here is Sticky note functionality. Text wrap working and font size changes w.r.t sticky note width and height. Editing mode activates on double click.
export const createStickyNotes = (canvas, options) => {
fabric.StickyNote = fabric.util.createClass(fabric.Group, {
type: "StickyNote",
initialize: function (options) {
this.set(options);
var height = this.height;
var width = this.width;
this.rectObj = new fabric.Rect({
width: width,
height: height,
fill: this.rectObj?.fill ?? "rgba(251,201,112,1)",
originX: "center",
originY: "center",
objectCaching: false,
stateProperties: ["fill"],
});
this.textObj = new fabric.Textbox(this.textObj?.text ?? "Notes", {
originX: "center",
originY: "center",
textAlign: "center",
width: 100,
hasControls: false,
fontSize: this.textObj?.fontSize ?? 30,
lineHeight: 1,
stateProperties: ["text", "fontSize"],
scaleX: this.textObj?.scaleX ?? 1,
scaleY: this.textObj?.scaleY ?? 1,
objectCaching: false,
breakWords: true,
fontFamily: "Open Sans",
});
this._objects = [this.rectObj, this.textObj];
// this custom _set function will set custom properties value to object when it will load from json.
// at that time loadFromJson function will call this initialize function.
// this._setCustomProperties(this.options);
canvas.renderAll();
//evenet will fire if the object is double clicked by mouse
this.on("mousedblclick", (e) => {
var pasteFlag = false;
var scaling = e.target.getScaledWidth() / 100;
var textForEditing;
canvas.bringToFront(e.target);
e.target.selectable = false;
const [rectObj, textObj] = this.getObjects();
textObj.clone(function (clonedObj) {
clonedObj.set({
left: e.target.left,
top: e.target.top,
lockMovementY: true,
lockMovementX: true,
hasBorders: false,
scaleX: scaling,
scaleY: scaling,
breakWords: true,
width: textObj.width,
stateProperties: [],
});
textForEditing = clonedObj;
});
this.remove(textObj);
canvas.add(textForEditing);
canvas.setActiveObject(textForEditing);
textForEditing.enterEditing();
textForEditing.selectAll();
textForEditing.paste = (function (paste) {
return function (e) {
disableScrolling();
pasteFlag = true;
};
})(textForEditing.paste);
textForEditing.on("changed", function (e) {
var fontSize = textForEditing.fontSize;
var charCount = Math.max(textForEditing._text.length, 1);
var charWR =
(textForEditing.textLines.length * width) / (charCount * fontSize);
if (textForEditing.height < height - 15) {
fontSize = Math.min(
Math.sqrt(
((height - 10 - fontSize) / 1.16) *
(width / (charCount * charWR))
),
30
);
}
if (textForEditing.height > height - 15) {
fontSize = Math.sqrt(
((height - 10) / 1.16) * (width / (charCount * charWR))
);
}
if (pasteFlag) {
pasteFlag = false;
while (
textForEditing.height > height - 15 &&
textForEditing.fontSize > 0
) {
fontSize = textForEditing.fontSize -= 0.2;
canvas.renderAll();
}
}
textForEditing.fontSize = fontSize;
});
textForEditing.on("editing:exited", () => {
enableScrolling();
canvas.setActiveObject(textObj);
textObj.set({
text: textForEditing.text,
fontSize: textForEditing.fontSize,
visible: true,
});
this.add(textObj);
this.selectable = true;
canvas.remove(textForEditing);
canvas.discardActiveObject();
});
});
function disableScrolling() {
var x = window.scrollX;
var y = window.scrollY;
window.onscroll = function () {
window.scrollTo(x, y);
};
}
var _wrapLine = function (_line, lineIndex, desiredWidth, reservedSpace) {
var lineWidth = 0,
splitByGrapheme = this.splitByGrapheme,
graphemeLines = [],
line = [],
// spaces in different languges?
words = splitByGrapheme
? fabric.util.string.graphemeSplit(_line)
: _line.split(this._wordJoiners),
word = "",
offset = 0,
infix = splitByGrapheme ? "" : " ",
wordWidth = 0,
infixWidth = 0,
largestWordWidth = 0,
lineJustStarted = true,
additionalSpace = splitByGrapheme ? 0 : this._getWidthOfCharSpacing();
reservedSpace = reservedSpace || 0;
desiredWidth -= reservedSpace;
for (var i = 0; i < words.length; i++) {
// i would avoid resplitting the graphemes
word = fabric.util.string.graphemeSplit(words[i]);
wordWidth = this._measureWord(word, lineIndex, offset);
offset += word.length;
// Break the line if a word is wider than the set width
if (this.breakWords && wordWidth >= desiredWidth) {
if (!lineJustStarted) {
graphemeLines.push(line);
line = [];
lineWidth = 0;
lineJustStarted = true;
}
this.fontSize *= desiredWidth / (wordWidth + 1);
// Loop through each character in word
for (var w = 0; w < word.length; w++) {
var letter = word[w];
var letterWidth =
(this.getMeasuringContext().measureText(letter).width *
this.fontSize) /
this.CACHE_FONT_SIZE;
line.push(letter);
lineWidth += letterWidth;
}
word = [];
} else {
lineWidth += infixWidth + wordWidth - additionalSpace;
}
if (lineWidth >= desiredWidth && !lineJustStarted) {
graphemeLines.push(line);
line = [];
lineWidth = wordWidth;
lineJustStarted = true;
} else {
lineWidth += additionalSpace;
}
if (!lineJustStarted) {
line.push(infix);
}
line = line.concat(word);
infixWidth = this._measureWord([infix], lineIndex, offset);
offset++;
lineJustStarted = false;
// keep track of largest word
if (wordWidth > largestWordWidth && !this.breakWords) {
largestWordWidth = wordWidth;
}
}
i && graphemeLines.push(line);
if (largestWordWidth + reservedSpace > this.dynamicMinWidth) {
this.dynamicMinWidth =
largestWordWidth - additionalSpace + reservedSpace;
}
return graphemeLines;
};
fabric.util.object.extend(fabric.Textbox.prototype, {
_wrapLine: _wrapLine,
});
function enableScrolling() {
window.onscroll = function () {};
}
},
toObject: function (propertiesToInclude) {
// This function is used for serialize this object. (used for create json)
// not inlclude this.textObj and this.rectObj into json because when object will load from json, init fucntion of this class is called and it will assign this two object textObj and rectObj again.
var obj = this.callSuper(
"toObject",
[
"objectCaching",
"textObj",
"rectObj",
// ... property list that you want to add into json when this object is convert into json using toJSON() function. (serialize)
].concat(propertiesToInclude)
);
// delete objects array from json because then object load from json, Init function will call. which will automatically re-assign object and assign _object array.
delete obj.objects;
return obj;
},
});
fabric.StickyNote.async = true;
fabric.StickyNote.fromObject = function (object, callback) {
// This function is used for deserialize json and convert object json into button object again. (called when we call loadFromJson() fucntion on canvas)
return fabric.Object._fromObject("StickyNote", object, callback);
};
return new fabric.StickyNote(options);
};
//How to use
var options = {
width: 100,
height: 100,
originX: "center",
originY: "center",
};
var notes = StickyNotes(canvas, options);
canvas.add(notes);

How to move object with keyboard in javascript

When I move the object, it's slow and doesn't move in diagonal, only up, down, right and left.
How can I fix this, is this a good way to start or should I do it otherwise?
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext('2d');
canvas.width = 600;
canvas.height = 600;
var object = {
height: 40,
width: 40,
x: 10,
y: 10,
color: "#FF0000"
}
document.addEventListener('keydown', function(event) {
//left
if(event.keyCode == 37) {
object.x -= 1;
}
//top
else if(event.keyCode == 38) {
object.y -= 1;
}
//right
else if(event.keyCode == 39) {
object.x += 1;
}
//bottom
else if(event.keyCode == 40) {
object.y += 1;
}
});
function renderCanvas(){
ctx.fillStyle = "#000000";
ctx.fillRect(0, 0, 600, 600);
}
function renderObject(){
ctx.fillStyle = "#FF0000";
ctx.fillRect(object.x, object.y, object.width, object.height);
}
function run(){
renderCanvas();
renderObject();
}
setInterval(run, 10);
Here's a jsfiddle
I'm kind of a newbie in javascript and I really need help on this ;)

Use flags or an object with flags that is updated when keys are pressed and released:
var Keys = {
up: false,
down: false,
left: false,
right: false
};
Then update in key events:
window.onkeydown = function(e) {
var kc = e.keyCode;
e.preventDefault();
if (kc === 37) Keys.left = true; // only one key per event
else if (kc === 38) Keys.up = true; // so check exclusively
else if (kc === 39) Keys.right = true;
else if (kc === 40) Keys.down = true;
};
window.onkeyup = function(e) {
var kc = e.keyCode;
e.preventDefault();
if (kc === 37) Keys.left = false;
else if (kc === 38) Keys.up = false;
else if (kc === 39) Keys.right = false;
else if (kc === 40) Keys.down = false;
};
This will now allow you to check keys that are pressed at the same time (if you want to move continuously you need to check status of the key object in a loop or else you will get a repeat delay):
if (Keys.up) {
dy+=3;
}
else if (Keys.down) { // both up and down does not work so check excl.
dy-=3;
}
if (Keys.left) {
dx+=3;
}
else if (Keys.right) {
dx-=3;
}
FIDDLE

Flags, yes, but 2 is plenty: dx and dy:
http://jsfiddle.net/rudiedirkx/paw4X/1/
var dx = 0, dy = 0;
var speed = 100; // px per second
var activeKey = 0;
document.addEventListener('keydown', function(e) {
if (activeKey == e.keyCode) return;
activeKey = e.keyCode;
//left
if (e.keyCode == 37) {
console.log('start moving LEFT');
dx = -1;
}
//top
else if (e.keyCode == 38) {
console.log('start moving UP');
dy = -1;
}
//right
else if (e.keyCode == 39) {
console.log('start moving RIGHT');
dx = 1;
}
//bottom
else if (e.keyCode == 40) {
console.log('start moving DOWN');
dy = 1;
}
});
document.addEventListener('keyup', function(e) {
switch (e.keyCode) {
case 37: // left
case 39: // right
console.log('stop moving HOR');
dx = 0;
break;
case 38: // up
case 40: // down
console.log('stop moving VER');
dy = 0;
break;
}
activeKey = 0;
});
function fun(){
renderCanvas();
object.x += dx / 60 * speed;
object.y += dy / 60 * speed;
renderObject();
requestAnimationFrame(fun);
}
requestAnimationFrame(fun);
The ugly activeKey part is necessary, because some keyboards repeat the keydown event every X ms until the key is released.

var object = {
height: 40,
width: 40,
x: 10,
y: 10,
color: "#FF0000"
}
You seem to have forgotten a semicolon. Let me show you:
var object = {
height: 40,
width: 40,
x: 10,
y: 10,
color: "#FF0000"
};

How about using the number-pad keys?
These number keys are already marked with the up/down/left/right arrowkeys so using 1,3,7,9 for diagonal moves would be understandable and convenient for the user.
To speed up your movement, you can add more than 1 pixel with each keystroke.
To move diagonally, you'll want to change both the object.x and object.y values simultaneously.
// move 4 pixels with each key
var distance=4;
// for example, move diagonally up & left
object.x-=distance;
object.y-=distance;
Here's example code and a Demo: http://jsfiddle.net/m1erickson/RnJLZ/
<!doctype html>
<html>
<head>
<link rel="stylesheet" type="text/css" media="all" href="css/reset.css" /> <!-- reset css -->
<script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
<style>
body{ background-color: ivory; }
canvas{border:1px solid red;}
</style>
<script>
$(function(){
var canvas=document.getElementById("canvas");
var ctx=canvas.getContext("2d");
var distance=4;
var object = {
height: 40,
width: 40,
x: 10,
y: 10,
color: "#FF0000"
}
renderObject();
document.body.onkeydown=function(event){
switch(event.keyCode){
case 97: // 1
object.x-=distance;
object.y+=distance;
break;
case 98: // 2
object.x+=0;
object.y+=distance;
break;
case 99: // 3
object.x+=distance;
object.y+=distance;
break;
case 100: // 4
object.x-=distance;
object.y+=0;
break;
case 101: // 5
object.x+=0;
object.y+=0;
break;
case 102: // 6
object.x+=distance;
object.y+=0;
break;
case 103: // 7
object.x-=distance;
object.y-=distance;
break;
case 104: // 8
object.x+=0;
object.y-=distance;
break;
case 105: // 9
object.x+=distance;
object.y-=distance;
break;
}
renderObject();
}
function renderObject(){
if(ctx.fillStyle!=object.color.toLowerCase()){
console.log(ctx.fillStyle,object.color);
ctx.fillStyle=object.color;
}
ctx.clearRect(0,0,canvas.width,canvas.height);
ctx.fillRect(object.x,object.y,object.width,object.height);
}
}); // end $(function(){});
</script>
</head>
<body>
<canvas id="canvas" width=300 height=300></canvas>
</body>
</html>

I tried and it looks like you had to set flags. I came up with this: http://jsfiddle.net/medda86/y6WU9/
html
<div class="pic"></div>
css
html,body{
width:100%;
height:100%;
margin:0px;}
.pic{
position:absolute;
margin-left:100px;
margin-top:100px;
width:100px;
height:100px;
background-color:#ccc;}
jquery
// MOVE OBJECT DIAGONALLY
$(document).ready(function(){
var movementSpeed = 10;
var intervalSpeed = 60;
var runAnimation = false;
var animationSpeed = 10;
var leftMarginLimit = parseInt($('.pic').parent().css('width')) - parseInt($('.pic').css('width'));
var topMarginLimit = parseInt($('.pic').parent().css('height')) - parseInt($('.pic').css('height'));
var leftMargin = parseInt($('.pic').css('margin-left'));
var topMargin = parseInt($('.pic').css('margin-top'));
var animationComplete = true;
// flags
var left = false;
var right = false;
var up = false;
var down = false;
$(document).keyup(function(key) {
if (key.which == 37){left = false;}
if (key.which == 39){right = false;}
if (key.which == 38){up = false;}
if (key.which == 40){down = false;}
});
$(document).keydown(function(key) {
if (key.which == 37){left = true;}
if (key.which == 39){right = true;}
if (key.which == 38){up = true;}
if (key.which == 40){down = true;}
});
setInterval(runMovement,intervalSpeed);
function runMovement() {
if (animationComplete){
// LEFT
if (left){
leftMargin -=movementSpeed;
if (leftMargin < 0){leftMargin = 0;}
if (leftMargin > leftMarginLimit){leftMargin = leftMarginLimit;}
}
// RIGHT
if (right){
leftMargin +=movementSpeed;
if (leftMargin < 0){leftMargin = 0;}
if (leftMargin > leftMarginLimit){leftMargin = leftMarginLimit;}
}
// UP
if (up){
topMargin -=movementSpeed;
if (topMargin < 0){topMargin = 0;}
if (topMargin > topMarginLimit){topMargin = topMarginLimit;}
}
// DOWN
if (down){
topMargin +=movementSpeed;
if (topMargin < 0){topMargin = 0;}
if (topMargin > topMarginLimit){topMargin = topMarginLimit;}
}
// ANIMATION?
if (runAnimation){
animationComplete = false;
$('.pic').animate({'margin-left': leftMargin+'px','margin-top': topMargin+'px'},animationSpeed,function(){
animationComplete = true;
});
}
else{
$('.pic').css({'margin-left': leftMargin+'px','margin-top': topMargin+'px'});
}
}
}
});
You can change theese settings, like how fast to move object and if you wanna run the animation, and set the animationspeed. Also you cna set the interval here.. game speed :P
var movementSpeed = 10;
var intervalSpeed = 60;
var runAnimation = false;
var animationSpeed = 10;
EDIT: I had to add the setinterval, got a bit buggy the other way with keydown and keyup. Now you can move all around more smoothly :)

KineticJs - When dynamically creating rect, the rect behind it drags by itself

In kineticjs I am creating dynamic rectangles that are draggable. However when I create a new rectangle, the rectangle behind it automatically drags. I dont want this to happen.
You can see the behaviour in demo at http://jsfiddle.net/sandeepy02/8kGVD/12/
Step 1: Choose "create rectangle" and create rectangles.
Step 2: Choose "Move rectangle" and move the rectangles.
Step 3: Choose "create rectangle" and create rectangles. This causes the rectangles previously created to also move. This is unwanted.
<html>
<head>
<script>
function valButton(radios) {
var btn = document.getElementsByName(radios);
var cnt = -1;
for (var i = btn.length - 1; i > -1; i--) {
if (btn[i].checked) {
cnt = i;
i = -1;
}
}
if (cnt > -1) return btn[cnt].value;
else return null;
}
window.onload = function() {
layer = new Kinetic.Layer();
stage = new Kinetic.Stage({
container: "container",
width: 320,
height: 320
});
background = new Kinetic.Rect({
x: 0,
y: 0,
width: stage.getWidth(),
height: stage.getHeight(),
fill: "white"
});
layer.add(background);
stage.add(layer);
moving = false;
stage.on("mousedown touchstart", function() {
var btnName = valButton("group2");
if (btnName == "1") {
if (moving) {
moving = false;
layer.draw();
} else {
var mousePos = stage.getMousePosition();
rect = new Kinetic.Rect({
x: 22,
y: 7,
width: 0,
height: 0,
fill: 'red',
stroke: 'black',
strokeWidth: 4,
draggable: true
});
layer.add(rect);
//start point and end point are the same
rect.setX(mousePos.x);
rect.setY(mousePos.y);
rect.setWidth(0);
rect.setHeight(0);
moving = true;
layer.drawScene();
}
}
document.all.text.innerText = btnName +" "+moving;
}); //end of mousedown
stage.on("mousemove touchmove", function() {
var btnName = valButton("group2");
if (btnName == "1") {
if (moving) {
var mousePos = stage.getMousePosition();
var x = mousePos.x;
var y = mousePos.y;
rect.setWidth(mousePos.x - rect.getX());
rect.setHeight(mousePos.y - rect.getY());
moving = true;
layer.drawScene();
}
}
else if (btnName == "3") {
layer.draw();
}
document.all.text.innerText = btnName +" "+moving;
}); //end of mousemove
stage.on("mouseup touchend", function() {
var btnName = valButton("group2");
if (btnName == "1") {
moving = false;
}
document.all.text.innerText = btnName +" "+moving;
}); //end of mouseup
};
</script>
</head>
<body>
<h2>Toggle buttons</h2>
<div class="toggle-btn-grp">
<label onclick="" class="toggle-btn"><input type="radio" value="1" name="group2"/> Create Rectangle</label>
<label onclick="" class="toggle-btn"><input type="radio" value="3" name="group2"/>Move Rectangle</label>
</div>
<div id="container" ></div>
<div id="text" >abc</div>
</body>
</html>​

Here is your updated function to fix the problem -
stage.on("mousedown touchstart", function() {
var btnName = valButton("group2");
if (btnName == "Create") {
if (moving) {
moving = false;
layer.draw();
} else {
var mousePos = stage.getMousePosition();
rect = new Kinetic.Rect({
x: 0,
y: 0,
width: 0,
height: 0,
fill: 'red',
stroke: 'black',
strokeWidth: 4,
draggable: true
});
layer.add(rect);
//start point and end point are the same
rect.setX(mousePos.x);
rect.setY(mousePos.y);
rect.setWidth(0);
rect.setHeight(0);
moving = true;
rect.on("mousemove touchmove", function() {
var btnName = valButton("group2");
if (btnName == "Create") {
this.setDraggable(false);
}
else if (btnName == "Move") {
this.setDraggable(true);
}
document.all.text.innerText = btnName +" rect move MovingFlag: "+moving;
}); //end of rect mousemove
layer.drawScene();
}
}
document.all.text.innerText = btnName +" MovingFlag: "+moving;
}); //end of mousedown