When and which lazyloadcontainer method(event) are called(triggered)?

Lazyload is a simple concept, and easy to understand. But when I look into the api, I could not found the trigger enter point.

Could you explain in a little bit more detail what trigger point you are referring to. Also, are you talking about LazyQueryContainer or LazyList in the Viritin addon?

These are method Containter interface defined:

    public Item getItem(Object itemId);
    public Collection<?> getContainerPropertyIds();
    public Collection<?> getItemIds();
    public Property getContainerProperty(Object itemId, Object propertyId);

    public Class<?> getType(Object propertyId);
    public int size();

    public boolean containsId(Object itemId);

    public Item addItem(Object itemId) throws UnsupportedOperationException;

    public Object addItem() throws UnsupportedOperationException;

    public boolean removeItem(Object itemId)
            throws UnsupportedOperationException;

    public boolean addContainerProperty(Object propertyId, Class<?> type,
            Object defaultValue) throws UnsupportedOperationException;

    public boolean removeContainerProperty(Object propertyId)
            throws UnsupportedOperationException;

    public boolean removeAllItems() throws UnsupportedOperationException;

My question is which method got called or what event submited when vaadin table scroll to next page.

I want to know the logic path from user scrolling table to container loading items.

Just means lazy load concept, not talking to any addons.I perfer to implement my own.

Ok, in that case I would suggest that you study the two containers I mentioned in my earlier post. And a word of caution: building a container isn’t an entrirely trivial thing to do, so you may want to consider using an existing container if possible.