README.md

Lite Renderer Add-on

[EXPERIMENTAL] A Renderer for Vaadin Flow that uses a component instance as template, intended for use as an alternative to LitRenderer.

grid.addColumn(LiteRenderer.<Person>of(
    new Button("Update", ev->handleUpdate(LiteRenderer.getItem(ev, Item.class))),
    new Button("Update", ev->handleRemove(LiteRenderer.getItem(ev, Item.class)));

Instead of:

grid.addColumn(LitRenderer.<Person>of(
     "<button @click=\"${handleUpdate}\">Update</button>" +
     "<button @click=\"${handleRemove}\">Remove</button>")
    .withFunction("handleUpdate", person -> { ... })
    .withFunction("handleRemove", person -> { ... })        
)

Features

• Use component instances as template, instead of the HTML approach used by LitRenderer.
• The component is rewritten as a lit template.

Online demo

Online demo here

Download release

Available in Vaadin Directory

Maven install

Add the following dependencies in your pom.xml file:

<dependency>
   <groupId>com.flowingcode.vaadin.addons</groupId>
   <artifactId>lite-renderer-addon</artifactId>
   <version>X.Y.Z</version>
</dependency>

Release versions are available from Maven Central repository. For SNAPSHOT versions see here.

Building and running demo

• git clone repository
• mvn clean install jetty:run

To see the demo, navigate to http://localhost:8080/

Release notes

See here

Issue tracking

The issues for this add-on are tracked on its github.com page. All bug reports and feature requests are appreciated.

Contributions

Contributions are welcome, but there are no guarantees that they are accepted as such.

As first step, please refer to our Development Conventions page to find information about Conventional Commits & Code Style requirements.

Then, follow these steps for creating a contribution:

• Fork this project.
• Create an issue to this project about the contribution (bug or feature) if there is no such issue about it already. Try to keep the scope minimal.
• Develop and test the fix or functionality carefully. Only include minimum amount of code needed to fix the issue.
• For commit message, use Conventional Commits to describe your change.
• Send a pull request for the original project.
• Comment on the original issue that you have implemented a fix for it.

License & Author

This add-on is distributed under Apache License 2.0. For license terms, see LICENSE.txt.

Lite Renderer Add-On is written by Flowing Code S.A.

Developer Guide

Getting started

• Use component instances as template:

    Div template = new Div(
        new Image("${item.pictureUrl}", "Portrait of ${item.firstName} ${item.lastName}"),
        new Div("${item.firstName} ${item.lastName}"),
        new Div("${item.profession}"));

    comboBox.setRenderer(LiteRenderer.<Person>of(template)
        .withProperty("pictureUrl", Person::pictureUrl)
        .withProperty("firstName", Person::firstName)
        .withProperty("lastName", Person::lastName)
        .withProperty("profession", Person::profession));

• withAttribute and withListener are fluent methods that allow setting attributes and listeners:

    Div div = new Div("${item.firstName} ${item.lastName}");
    grid.addColumn(LiteRenderer.<Person>of(div)
        .withProperty("firstName", Person::firstName)
        .withProperty("lastName", Person::lastName)
        .withProperty("age", Person::age)
        .withAttribute(div, "tooltip", "Age: ${item.age}")
        .withAttribute(div, "style", person-> "color: "+ (person.age()<18?"red":"blue"))
        .withListener(div, "click", item -> {
          Notification.show(item.firstName() + " " + item.lastName() + " Clicked!");
        }
    ));

• Wrapping a component with LiteComponent allows fluent setters for attributes, properties, and listeners, removing the need for variables.

    Div div = new Div("${item.firstName} ${item.lastName}");
    grid.addColumn(LiteRenderer.<Person>of(div)
        .withProperty("firstName", Person::firstName)
        .withProperty("lastName", Person::lastName)
        .withProperty("age", Person::age)
        .withAttribute(div, "tooltip", "Age: ${item.age}")
        .withAttribute(div, "style", person-> "color: "+ (person.age()<18?"red":"blue"))
        .withListener(div, "click", item -> {
          Notification.show(item.firstName() + " " + item.lastName() + " Clicked!");
        }
    ));

• Listeners can also receive more data in addition to the item:

    TextField tf = new TextField();
    grid.addColumn(LiteRenderer.<Person>of(tf).withListener(tf, "change", (item, args) -> {
              Notification.show(item.firstName()
              + " " + item.lastName()
              + " says: " + args.getString(0));
    }, "event.target.value"));

• The click event of a template Button is called when the button is clicked. Within the event listener, LiteRenderer.getItem(ev, Person.class) returns the current item:

    grid.addColumn(LiteRenderer.<Person>of(new Button("Click", ev->{
      var item = LiteRenderer.getItem(ev, Person.class);
      Notification.show(item.firstName() + " " + item.lastName() + " Clicked!");
    })));

• Flow Viritin components enable more fluent method chaining:

    grid.addColumn(LiteRenderer.<Person>of(
            VSpan.of("${item.firstName} ${item.lastName}")
                 .withStyle("color", "${item.color}"))
         .withProperty("color", person->person.age()<18?"red":"blue")
         .withProperty("firstName", Person::firstName)
         .withProperty("lastName", Person::lastName));