Sliding user experience not "as used to" on iPhone

Hi! We use ember-side-menu in our video editor application and cordova app. Thanks for sharing!

On IPhone 6s (my test device), iOS 9.3 the slide to open and slide to close action needs dragging across half of the menu width until the threshold is reached.

I noticed, that changedTouches on touchEnd contains the same pageX as the start event most times. But the current pageX is given as originalEvent.pageX in iOS. => velocityX = 0 most times => threshold passed 50%? complete : abort

This feels a little bit jerky. So i tried to improve it. It is not tested in the field yet, only on three devices and chrome. Maybe i post an update later. The current solution is to change _completeMenuTransition to this:

    _completeMenuTransition(event) {
        const progress = get(this, "progress");
        const touchStartEvent = get(this, "touchStartEvent");
        const side = get(this, "side");
        const velocityX = this._calculateVelocityX(
            touchStartEvent.originalEvent.touches[0].pageX,
            touchStartEvent.originalEvent.timeStamp,
            typeof event.originalEvent.pageX !== "undefined"? event.originalEvent.pageX : event.originalEvent.changedTouches[0].pageX,
            event.originalEvent.timeStamp
        );
        const minClosingVelocity = 0.000001;
        const isSwipingLeft = velocityX > minClosingVelocity;
        const isSwipingRight = velocityX < -minClosingVelocity;

        const isClosingMovement = (side === "left" && isSwipingLeft) ||
            (side === "right" && isSwipingRight);
        const isOpeningMovement = (side === "left" && isSwipingRight) ||
            (side === "right" && isSwipingLeft);

        if (isClosingMovement) {
            get(this, "sideMenu").close();
        } else if (isOpeningMovement) {
            get(this, "sideMenu").open();
        }
    },

tsubik / ember-side-menu

Sliding user experience not "as used to" on iPhone #6