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java - Vaadin Grid vs Table

What is the difference between the Grid and Table components in Vaadin 7?

Which should I use, and when?

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Summary

Grid → New & Amazing
Table → Venerable & Reliable

Table is a very good data-grid display widget built into the earliest versions of Vaadin.

Grid is grand rewrite from scratch, designed to supplant Table. The Vaadin team is leveraging their wisdom gained from experience, “if we knew then what we know now”, to make the very best data-grid possible given today’s Web technology. Grid is such a big deal that it gets its own vanity page. See this company blog post for a quick overview.

So, generally speaking, I suggest you focus on Grid. Try it out, learn it first, and see if it meets your needs. If you run into bugs or problems, or you have need features lacking in Grid, then fallback to Table. You can mix-and-match both in a project, with the caveat that the different appearance and behavior may confuse your users.

Think of Grid as the precocious adolescent full of promise and eager to make the leap into adulthood, and Table as the mature grownup working hard in its prime years of middle-age while dreaming of a well-earned future retirement sailing into the sunset.

Details

If using Vaadin 6, on a continuing project or you need to support very old browsers, then Table is your only choice. Grid requires Vaadin 7 or later.

Here are some major Table features currently lacking in Grid.

  • Drag-and-drop features (to be added later).
  • Resize column by user dragging edge of column header.

Both share many features. They practice lazy-loading to the browser, automatically loading data only as needed from the server-side so as to not overload the web browser. Both allow the user to drag columns to re-order. Both let the user show/hide columns.

Row Selection

Both allow selecting single rows or multiple rows.

Grid also has an automatic feature where it adds a column of checkboxes. The user can select multiple rows by clicking those checkboxes rather than using a mouse or mouse+keyboard. Many, if not most, users are clumsy with mouse-driven multiple row selection. See this screenshot, and notice the very first column.

The programming support for selection is different. Grid does not extend AbstractSelect, instead defines its own selection API. Call addSelectionListener() and define a SelectionListener. See The Book Of Vaadin.

Headers & Footers

Both have headers and footers, but Grid has more options. Grid can place widgets instead of text. Grid can have multiple rows of headers. Grid can join header cells, like spanning in an HTML table.

In-Place Editing

Both provide in-place editing of data, but in different ways. Table allows editing of data in the cell. Grid took a different approach, for editing the entire row by displaying a mini-window, a little data-entry form. This form includes a pair of confirmation & cancellation buttons. This form is much more flexible than Table’s cell-editing.

Filtering

Grid offers user-controlled filtering, where a row of enterable cells appears below the headers. As users type a filter is applied to show only matching rows. See this screenshot. With Table, you need to create some kind of user-interface and apply the filtering.

Backed By Data Container

UPDATE: Vaadin 8 brings a new version of Grid that leverages a newly improved and greatly simplified data model. This is a major reason to use Grid instead of Table. Note that both the original Grid as well as Table are still available in Vaadin 8 via the Vaadin 7 compatibility layer.

The following old info left intact…

Both Table and Grid are a presentation-only widget, backed by a separate data object implementing the Container interface according to the Vaadin Data Model.

The Table class also acts as a Container which always confused me. I’m glad to see Grid maintain a more clear distinct separation.

Like Table, Grid does offer some convenience methods for quick-and-dirty situations where you want to throw some data at the Grid itself without formally producing a Container. But Grid’s convenience methods use row and column terms in contrast to the Container’s item and property terms. These terms make it more clear that your are talking to the Grid but the Grid is acting on its default attached IndexedContainer instance on your behalf.

Cell Content

UPDATE: In Vaadin 8.1, Grid gains the ability to display a Component in a cell. See a live demo of the Component Renderer.

Cell content handling is different. Grid cannot directly display column icons, nor can it place components (widgets) in a cell. Instead used the new Renderer features.

Doc & Demo

Both have a chapter in The Book Of Vaadin, one for Table and one for Grid.

Both have a live demos. One for Table (and TreeTable). And a couple for Grid, one full-window and one with various aspects.

See this brochure page for Grid, including an embedded live demo, with a link to further demos.

Miscellaneous Differences

Grid has a built-in widget for displaying a number as a small thermometer widget. See this screenshot, in the last column.

For more specific differences, see section 5.24.1 Overview –?Differences To Table in The Book Of Vaadin.

Esoterica… Grid is the first component in Vaadin Components, a high quality set of Web Components built on Google Polymer that is ready to be used with any framework that supports Web Components. While the Vaadin team has promised to support Table for years in the future, don’t expect it to receive such special attention.

Vaadin 8

In Vaadin 8.0 and 8.1, Grid is getting even better. Major enhancements include:

  • Works with the simpler sleeker data model new in Vaadin 8
    • Pass a collection of entities for display
    • Easily define columns with type-safe lambda syntax
      grid.addColumn( Person::getFirstName ).setCaption( "First Name" );
    • Easier lazy-loading of data now that Container is gone:
      grid.setDataProvider( ( sortorder , offset , limit) -> service.findAll( offset , limit) , () -> service.count() );
  • The ability to display Vaadin components rather than just renderers
  • Drag-and-drop via the drag-and-drop support defined by HTML5.
  • Even more speed

The Table component is still available via the Compatibility layer in Vaadin 8 for continuing the use of Vaadin 7 classes.

Future

The Vaadin team has great plans for Grid, so much of what you read on StackOverflow page will change. The team will be eagerly adding features, enhancements, and bug fixes in the coming months and years. Many enhancements have already been made to Grid in its short history, so beware when reading older documents about limitations or lacking features –?that may not be so anymore.


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