/* const wrapper = document.getElementById("signature-pad"); */
/* const clearButton = wrapper.querySelector("[data-action=clear]"); */
const changeBackgroundColorButton = wrapper.querySelector("[data-action=change-background-color]");
const changeColorButton = wrapper.querySelector("[data-action=change-color]");
const changeWidthButton = wrapper.querySelector("[data-action=change-width]");
const undoButton = wrapper.querySelector("[data-action=undo]");
const savePNGButton = wrapper.querySelector("[data-action=save-png]");
const saveJPGButton = wrapper.querySelector("[data-action=save-jpg]");
const saveSVGButton = wrapper.querySelector("[data-action=save-svg]");
const saveSVGWithBackgroundButton = wrapper.querySelector("[data-action=save-svg-with-background]");
/* for (let c = 0; c <= 99; i++) {
var canvas_id = c
new SignaturePad(canvas, {
// It's Necessary to use an opaque color when saving image as JPEG;
// this option can be omitted if only saving as PNG or SVG
backgroundColor: 'rgb(255, 255, 255)'
});
const canvas = wrapper.querySelector("canvas"+canvas_id);
}
*/
const canvas = wrapper.querySelector(".canvasSp");
const signaturePad = new SignaturePad(canvas, {
minWidth: 1.5,
maxWidth: 1.5,
// It's Necessary to use an opaque color when saving image as JPEG;
// this option can be omitted if only saving as PNG or SVG
backgroundColor: 'rgb(255, 255, 255)'
});
// Adjust canvas coordinate space taking into account pixel ratio,
// to make it look crisp on mobile devices.
// This also causes canvas to be cleared.
function resizeCanvas() {
// When zoomed out to less than 100%, for some very strange reason,
// some browsers report devicePixelRatio as less than 1
// and only part of the canvas is cleared then.
const ratio = Math.max(window.devicePixelRatio || 1, 2);
// This part causes the canvas to be cleared
canvas.width = canvas.offsetWidth * ratio;
canvas.height = canvas.offsetHeight * ratio;
canvas.getContext("2d").scale(ratio, ratio);
// This library does not listen for canvas changes, so after the canvas is automatically
// cleared by the browser, SignaturePad#isEmpty might still return false, even though the
// canvas looks empty, because the internal data of this library wasn't cleared. To make sure
// that the state of this library is consistent with visual state of the canvas, you
// have to clear it manually.
//signaturePad.clear();
// If you want to keep the drawing on resize instead of clearing it you can reset the data.
signaturePad.fromData(signaturePad.toData(),{ clear: false });
}
// On mobile devices it might make more sense to listen to orientation change,
// rather than window resize events.
$('signature-pad--body').onresize = resizeCanvas;
resizeCanvas();
function download(dataURL, filename) {
const blob = dataURLToBlob(dataURL);
const url = window.URL.createObjectURL(blob);
const a = document.createElement("a");
a.style = "display: none";
a.href = url;
a.download = filename;
document.body.appendChild(a);
a.click();
window.URL.revokeObjectURL(url);
}
// One could simply use Canvas#toBlob method instead, but it's just to show
// that it can be done using result of SignaturePad#toDataURL.
function dataURLToBlob(dataURL) {
// Code taken from https://github.com/ebidel/filer.js
const parts = dataURL.split(';base64,');
const contentType = parts[0].split(":")[1];
const raw = window.atob(parts[1]);
const rawLength = raw.length;
const uInt8Array = new Uint8Array(rawLength);
for (let i = 0; i < rawLength; ++i) {
uInt8Array[i] = raw.charCodeAt(i);
}
return new Blob([uInt8Array], { type: contentType });
}
/*
clearButton.addEventListener("click", () => {
signaturePad.clear();
});
undoButton.addEventListener("click", () => {
const data = signaturePad.toData();
if (data) {
data.pop(); // remove the last dot or line
signaturePad.fromData(data);
}
});
changeBackgroundColorButton.addEventListener("click", () => {
const r = Math.round(Math.random() * 255);
const g = Math.round(Math.random() * 255);
const b = Math.round(Math.random() * 255);
const color = "rgb(" + r + "," + g + "," + b +")";
signaturePad.backgroundColor = color;
const data = signaturePad.toData();
signaturePad.clear();
signaturePad.fromData(data);
});
changeColorButton.addEventListener("click", () => {
const r = Math.round(Math.random() * 255);
const g = Math.round(Math.random() * 255);
const b = Math.round(Math.random() * 255);
const color = "rgb(" + r + "," + g + "," + b +")";
signaturePad.penColor = color;
});
changeWidthButton.addEventListener("click", () => {
const min = Math.round(Math.random() * 100) / 10;
const max = Math.round(Math.random() * 100) / 10;
signaturePad.minWidth = Math.min(min, max);
signaturePad.maxWidth = Math.max(min, max);
});
savePNGButton.addEventListener("click", () => {
if (signaturePad.isEmpty()) {
alert("Please provide a signature first.");
} else {
const dataURL = signaturePad.toDataURL();
download(dataURL, "signature.png");
}
});
saveJPGButton.addEventListener("click", () => {
if (signaturePad.isEmpty()) {
alert("Please provide a signature first.");
} else {
const dataURL = signaturePad.toDataURL("image/jpeg");
download(dataURL, "signature.jpg");
}
});
saveSVGButton.addEventListener("click", () => {
if (signaturePad.isEmpty()) {
alert("Please provide a signature first.");
} else {
const dataURL = signaturePad.toDataURL('image/svg+xml');
download(dataURL, "signature.svg");
}
});
saveSVGWithBackgroundButton.addEventListener("click", () => {
if (signaturePad.isEmpty()) {
alert("Please provide a signature first.");
} else {
const dataURL = signaturePad.toDataURL('image/svg+xml', {includeBackgroundColor: true});
download(dataURL, "signature.svg");
}
});
*/