我使用jQuery。点击来处理Raphael图形上的鼠标点击事件，同时，我需要处理鼠标拖动事件，鼠标拖动在Raphael中由鼠标下拉，鼠标上拉和鼠标移动组成。
很难区分点击和拖动，因为点击也包含鼠标下拉和鼠标上拉，我怎么能区分鼠标“点击”和鼠标“拖动”然后在Javascript?
当前回答
你可以这样做:
var div = document.getElementById("div"); div.addEventListener("mousedown", function() { window.addEventListener("mousemove", drag); window.addEventListener("mouseup", lift); var didDrag = false; function drag() { //when the person drags their mouse while holding the mouse button down didDrag = true; div.innerHTML = "drag" } function lift() { //when the person lifts mouse if (!didDrag) { //if the person didn't drag div.innerHTML = "click"; } else div.innerHTML = "drag"; //delete event listeners so that it doesn't keep saying drag window.removeEventListener("mousemove", drag) window.removeEventListener("mouseup", this) } }) body { outline: none; box-sizing: border-box; margin: 0; padding: 0; font-family: Arial, Helvetica, sans-serif; overflow: hidden; } #div { /* calculating -5px for each side of border in case border-box doesn't work */ width: calc(100vw - 10px); height: calc(100vh - 10px); border: 5px solid orange; background-color: yellow; font-weight: 700; display: grid; place-items: center; user-select: none; cursor: pointer; padding: 0; margin: 0; } <html> <body> <div id="div">Click me or drag me.</div> </body> </html>
其他回答
基于这个答案，我在React组件中这样做:
export default React.memo(() => {
const containerRef = React.useRef(null);
React.useEffect(() => {
document.addEventListener('mousedown', handleMouseMove);
return () => document.removeEventListener('mousedown', handleMouseMove);
}, []);
const handleMouseMove = React.useCallback(() => {
const drag = (e) => {
console.log('mouse is moving');
};
const lift = (e) => {
console.log('mouse move ended');
window.removeEventListener('mousemove', drag);
window.removeEventListener('mouseup', this);
};
window.addEventListener('mousemove', drag);
window.addEventListener('mouseup', lift);
}, []);
return (
<div style={{ width: '100vw', height: '100vh' }} ref={containerRef} />
);
})
来自@Przemek的回答，
函数listenClickOnly(元素，回调，阈值=10){ 让拖动= 0; 元素。addEventListener('mousedown'， () => drag = 0); 元素。addEventListener('mousemove'， () => drag++); 元素。addEventListener('mouseup'， e => { 如果(拖动<阈值)回调(e); })； ｝ listenClickOnly ( 文档, () => console.log('click')， 10 ）;
有同样的问题，最近在一个树列表中，用户可以点击项目或拖动它，使这个小指针类，并把它放在我的utils.js
function Pointer(threshold = 10) {
let x = 0;
let y = 0;
return {
start(e) {
x = e.clientX;
y = e.clientY;
},
isClick(e) {
const deltaX = Math.abs(e.clientX - x);
const deltaY = Math.abs(e.clientY - y);
return deltaX < threshold && deltaY < threshold;
}
}
}
下面你可以看到它的工作原理:
function Pointer(threshold = 10) { let x = 0; let y = 0; return { start(e) { x = e.clientX; y = e.clientY; }, isClick(e) { const deltaX = Math.abs(e.clientX - x); const deltaY = Math.abs(e.clientY - y); return deltaX < threshold && deltaY < threshold; } } } const pointer = new Pointer(); window.addEventListener('mousedown', (e) => pointer.start(e)) //window.addEventListener('mousemove', (e) => pointer.last(e)) window.addEventListener('mouseup', (e) => { const operation = pointer.isClick(e) ? "Click" : "Drag" console.log(operation) })
如果你想使用Rxjs:
var element = document; Rx.Observable .merge( Rx.Observable.fromEvent(element, 'mousedown').mapTo(0), Rx.Observable.fromEvent(element, 'mousemove').mapTo(1) ) .sample(Rx.Observable.fromEvent(element, 'mouseup')) .subscribe(flag => { console.clear(); console.log(flag ? "drag" : "click"); }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <script src="https://unpkg.com/@reactivex/rxjs@5.4.1/dist/global/Rx.js"></script>
这是@wong2在他的回答中所做的直接克隆，但转换为RxJs。
样本的使用也很有趣。示例操作符将从源(mousedown和mousemove的合并)中获取最新的值，并在内部观察对象(mouseup)发出时发出它。
正如mrjrdnthms在他对接受的答案的评论中指出的那样，这不再适用于Chrome(它总是触发鼠标移动)，我已经改编了Gustavo的答案(因为我使用jQuery)来解决Chrome的行为。
var currentPos = [];
$(document).on('mousedown', function (evt) {
currentPos = [evt.pageX, evt.pageY]
$(document).on('mousemove', function handler(evt) {
currentPos=[evt.pageX, evt.pageY];
$(document).off('mousemove', handler);
});
$(document).on('mouseup', function handler(evt) {
if([evt.pageX, evt.pageY].equals(currentPos))
console.log("Click")
else
console.log("Drag")
$(document).off('mouseup', handler);
});
});
Array.prototype.equals函数来自这个答案
