fromEvent
将使用on
and off
您传递给它的任何对象的方法,否则它将使用addEventListener
and removeEventListener
。因此,如果您使用 jQuery,您可以简单地选择所有这些并使用它(Observable.fromEvent($('.targetNode'), 'mouseup')
例如)。
否则,您可以使用任何带有on
and off
订阅或取消订阅事件的方法,就像我在下面所做的那样。
除此之外,您还可以使用target
财产在MouseEvent
你在每个流中获取的对象来获取你想要移动的实际 DOM 节点...
像下面的例子这样的东西应该可以解决问题。
(function (global) {
/**
selectNodes is a method to select a NodeList, but convert it to
a type that has `on` and `off` methods RxJS 2 expects to see for `fromEvent`
*/
function selectNodes(selector) {
var nodes = document.querySelectorAll(selector);
return {
// the selected nodes
nodes: [].slice.call(this.nodes),
// subscribe to an event on every selected node
on: function(eventName, handler) {
this.nodes.forEach(function(node) { node.addEventListener(eventName, handler); });
},
// unsubscribe from the event on every selected node
off: function(eventName, handler) {
this.nodes.forEach(function(node) { node.removeEventListener(eventName, handler); });
}
};
}
function main () {
// IMPORTANT CHANGE: Use the selectNodes method we made
var dragTargets = selectNodes('.dragTarget');
// Get the three major events
var mouseup = Rx.Observable.fromEvent(dragTargets, 'mouseup');
var mousemove = Rx.Observable.fromEvent(document, 'mousemove');
var mousedown = Rx.Observable.fromEvent(dragTargets, 'mousedown');
var mousedrag = mousedown.flatMap(function (md) {
// calculate offsets when mouse down
var startX = md.offsetX, startY = md.offsetY;
// Calculate delta with mousemove until mouseup
return mousemove.map(function (mm) {
mm.preventDefault();
return {
left: mm.clientX - startX,
top: mm.clientY - startY,
target: mm.target, // IMPORTANT CHANGE: the element you care about
};
}).takeUntil(mouseup);
});
// Update position
var subscription = mousedrag.subscribe(function (d) {
d.target.style.top = d.top + 'px';
d.target.style.left = d.left + 'px';
});
}
main();
}(window));