CanvasRenderingContext2D: drawFocusIfNeeded() method

drawFocusIfNeeded(element)
drawFocusIfNeeded(path, element)

<canvas id="canvas">
 <button id="button1">Continue</button>
 <button id="button2">Quit</button>
</canvas>

const canvas = document.getElementById("canvas");
const ctx = canvas.getContext("2d");
const button1 = document.getElementById("button1");
const button2 = document.getElementById("button2");
document.addEventListener("focus", redraw, true);
document.addEventListener("blur", redraw, true);
canvas.addEventListener("click", handleClick);
redraw();
function redraw() {
 ctx.clearRect(0, 0, canvas.width, canvas.height);
 drawButton(button1, 20, 20);
 drawButton(button2, 20, 80);
}
function handleClick(e) {
 // Calculate click coordinates
 const x = e.clientX - canvas.offsetLeft;
 const y = e.clientY - canvas.offsetTop;
 // Focus button1, if appropriate
 drawButton(button1, 20, 20);
 if (ctx.isPointInPath(x, y)) {
 button1.focus();
 }
 // Focus button2, if appropriate
 drawButton(button2, 20, 80);
 if (ctx.isPointInPath(x, y)) {
 button2.focus();
 }
}
function drawButton(el, x, y) {
 const active = document.activeElement === el;
 const width = 150;
 const height = 40;
 // Button background
 ctx.fillStyle = active ? "pink" : "lightgray";
 ctx.fillRect(x, y, width, height);
 // Button text
 ctx.font = "15px sans-serif";
 ctx.textAlign = "center";
 ctx.textBaseline = "middle";
 ctx.fillStyle = active ? "blue" : "black";
 ctx.fillText(el.textContent, x + width / 2, y + height / 2);
 // Define clickable area
 ctx.beginPath();
 ctx.rect(x, y, width, height);
 // Draw focus ring, if appropriate
 ctx.drawFocusIfNeeded(el);
}

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This page was last modified on ⁨Sep 25, 2025⁩ by MDN contributors.