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Start your free trialMaurice Tafolla- Cunningham
7,708 PointsNothing is drawing on the canvas
My problem is the title. I'm using Chrome- my code looks exactly the same as Andrew's from what I can tell and nothing is happening. Check out my code.
//Problem: No user inteatcion causes no changwe to application
//Solution: When user interacts causes changes approptiately
var color = $(".selected").css("background-color");
var $canvas = $("canvas");
var context = $canvas[0].getContext("2d");
// same as document.getElementsByTagName("canvas")[0]
var lastEvent;
var mouseDown = false;
//When clicking on control list items
$(".controls").on("click", "li", function(){
//Deselect sibling elements
$(this).siblings().removeClass("selected");
//Select clicked element
$(this).addClass("selected");
//cache current color
color = $(this).css("background-color");
});
//When "new color" is clicked
$("#revealColorSelect").click(function(){
//show color select or hide color select
changeColor();
$("#colorSelect").toggle();
});
//update new color span
function changeColor() {
var r = $("#red").val();
var g = $("#green").val();
var b = $("#blue").val();
$("#newColor").css("background-color", "rgb(" + r + "," + g + "," + b + ")");
}
//When color sliders change
$("input[type=range]").change(changeColor);
//When "add color" is pressed
$("#addNewColor").click(function(){
//append the color to the controls ul
var $newColor = $("<li></li>");
$newColor.css("background-color", $("#newColor").css("background-color"));
$(".controls ul").append($newColor);
//select the new color
$newColor.click();
});
//On mouse events on the canvas
$canvas.mousedown(function(e){
lastEvent = e;
mouseDown = true;
}).mousemove(function(e){
//Draw lines
if(mouseDown) {
context.beginPath();
context.moveTo(lastEvent.offsetX, lastEvent.offSetY);
context.lineTo(e.offsetX, e.offsetY);
context.strokeStyle = color;
context.stroke();
lastEvent = e;
}
}).mouseup(function(){
mouseDown = false;
});
1 Answer
rydavim
18,814 PointsLooks like there's just a minor typo in your mouse events.
context.moveTo(lastEvent.offsetX, lastEvent.offSetY); // offSetY should be offsetY (no capital s)
I think that should do it - everything else looks good. Happy coding! :)
Maurice Tafolla- Cunningham
7,708 PointsMaurice Tafolla- Cunningham
7,708 PointsSweet thanks for the extra eyes.