AngularJS指令仅用于向下滚动事件？

Question

我获得了滚动事件的指令，但我只想向下滚动事件。

.directive('whenScrolled', function() {
    return function(scope, elm, attr) {
        var raw = elm[0];

        elm.bind('scroll', function() {
            if (raw.scrollTop + raw.offsetHeight >= raw.scrollHeight) {
                scope.$apply(attr.whenScrolled);
            }
        });
    };
})

Answer 1

我已通过以下代码解决了这个问题。

//=========================================================================
// Custom Infinite Scoller for table edit 
//=========================================================================
.directive('whenScrolled', function() {
    return function(scope, elm, attr) {
        var raw = elm[0];

        ̶e̶l̶m̶.̶b̶i̶n̶d̶(̶'̶w̶h̶e̶e̶l̶'̶,̶ ̶f̶u̶n̶c̶t̶i̶o̶n̶(̶)̶ ̶{̶
        elm.bind('wheel', function(event) {
            var delta;
            if (event.wheelDelta){
                delta = event.wheelDelta;
            }else{
                delta = -1 *event.deltaY;
            }
            if (delta < 0){
                //call whenScrolled attribute to HTML for calling function from controller --- Scroll Up
                scope.$apply(attr.whenScrolled);

            }else if (delta > 0){
                //do nothing --- Scroll Down
            }
        });

    };
})