private boolean tryToNotifyReset() {
        if ((mStatus == PTR_STATUS_COMPLETE || mStatus == PTR_STATUS_PREPARE) && mPtrIndicator.isInStartPosition()) {
            if (mPtrUIHandlerHolder.hasHandler()) {
                mPtrUIHandlerHolder.onUIReset(this);
                if (DEBUG) {
                    PtrCLog.i(LOG_TAG, "PtrUIHandler: onUIReset");
                }
            }
            mStatus = PTR_STATUS_INIT;
            clearFlag();
            return true;
        }
        return false;
    }
If at the top and not in loading, reset
ptr-lib/src/in/srain/cube/views/ptr/PtrFrameLayout.java