54 lines
1.3 KiB
HTML
54 lines
1.3 KiB
HTML
<!doctype html>
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<html>
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<head>
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<meta charset="UTF-8">
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</head>
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<body style="height: 200px">
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<p>Drag the ball.</p>
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<img src="https://js.cx/clipart/ball.svg" style="cursor:pointer" width="40" height="40" id="ball">
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<script>
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ball.onmousedown = function(event) { // (1) start the process
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// (2) prepare to moving: make absolute and top by z-index
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ball.style.position = 'absolute';
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ball.style.zIndex = 1000;
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document.body.appendChild(ball);
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// ...and put that absolutely positioned ball under the cursor
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moveAt(event.pageX, event.pageY);
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// centers the ball at (pageX, pageY) coordinates
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function moveAt(pageX, pageY) {
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ball.style.left = pageX - ball.offsetWidth / 2 + 'px';
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ball.style.top = pageY - ball.offsetHeight / 2 + 'px';
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}
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function onMouseMove(event) {
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moveAt(event.pageX, event.pageY);
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}
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// (3) move the ball on mousemove
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document.addEventListener('mousemove', onMouseMove);
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// (4) drop the ball, remove unneeded handlers
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ball.onmouseup = function() {
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document.removeEventListener('mousemove', onMouseMove);
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ball.onmouseup = null;
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};
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};
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ball.ondragstart = function() {
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return false;
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};
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</script>
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</body>
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</html>
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