js触控

document.addEventListener('touchstart', handleTouchStart, false);
document.addEventListener('touchmove', handleTouchMove, false);

let xDown = null;
let yDown = null;

function handleTouchStart(evt) {
    const firstTouch = evt.touches[0];
    xDown = firstTouch.clientX;
    yDown = firstTouch.clientY;
}

function handleTouchMove(evt) {
    if (!xDown || !yDown) {
        return;
    }

    const xUp = evt.touches[0].clientX;
    const yUp = evt.touches[0].clientY;

    const xDiff = xDown - xUp;
    const yDiff = yDown - yUp;

    if (Math.abs(xDiff) > Math.abs(yDiff)) {
        if (xDiff > 0) {
            console.log('swipe left');
        } else {
            console.log('swipe right');
        }
    } else {
        if (yDiff > 0) {
            console.log('swipe up');
        } else {
            console.log('swipe down');
        }
    }

    xDown = null;
    yDown = null;
}

document.addEventListener('pointerdown', handlePointerDown, false);
document.addEventListener('pointermove', handlePointerMove, false);

function handlePointerDown(evt) {
    // 处理按下事件
}

function handlePointerMove(evt) {
    // 处理移动事件
}

let rafId;

function handleTouchMove(evt) {
    if (rafId) {
        cancelAnimationFrame(rafId);
    }

    rafId = requestAnimationFrame(() => {
        // 处理触摸移动逻辑
    });
}