ViewPortExtension is a UI component add-on for Vaadin 8.
Have you considered that there is no point for UI components that are not in visible iviewport to fetch data from backend and update themselves. This is essential for heavy dashboard apps. Thus I wrote this handy extension, which can extend Vaadin component to have isInViewPort() status and ViewPortStatusChangedEvent to help optimizing large dashboards.
Official releases of this add-on are available at Vaadin Directory. For Maven instructions, download and reviews, go to http://vaadin.com/addon/viewportextension
git clone mvn clean install cd demo mvn jetty:run
To see the demo, navigate to http://localhost:8080/
For further development of this add-on, the following tool-chain is recommended:
- Eclipse IDE
- m2e wtp plug-in (install it from Eclipse Marketplace)
- Vaadin Eclipse plug-in (install it from Eclipse Marketplace)
- JRebel Eclipse plug-in (install it from Eclipse Marketplace)
- Chrome browser
Choose File > Import... > Existing Maven Projects
Note that Eclipse may give "Plugin execution not covered by lifecycle configuration" errors for pom.xml. Use "Permanently mark goal resources in pom.xml as ignored in Eclipse build" quick-fix to mark these errors as permanently ignored in your project. Do not worry, the project still works fine.
If you have not already compiled the widgetset, do it now by running vaadin:install Maven target for viewportextension-root project.
If you have a JRebel license, it makes on the fly code changes faster. Just add JRebel nature to your viewportextension-demo project by clicking project with right mouse button and choosing JRebel > Add JRebel Nature
To debug project and make code modifications on the fly in the server-side, right-click the viewportextension-demo project and choose Debug As > Debug on Server. Navigate to http://localhost:8080/viewportextension-demo/ to see the application.
Debugging client side code in the viewportextension-demo project:
- run "mvn vaadin:run-codeserver" on a separate console while the application is running
- activate Super Dev Mode in the debug window of the application or by adding ?superdevmode to the URL
- You can access Java-sources and set breakpoints inside Chrome if you enable source maps from inspector settings.
- Rebuild against Vaadin 8.13. Avoids logged warnings with listeners.
- Improve demo
- Bugfix in horizontal position calculation
- Initial release, feedback is welcome
This component is developed as a hobby with no public roadmap or any guarantees of upcoming releases. If you have ideas for improvements, suggest them in issue tracker.
The issues for this add-on are tracked on its github.com page. All bug reports and feature requests are appreciated.
Contributions are welcome, but there are no guarantees that they are accepted as such. Process for contributing is the following:
- 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.
- Refer to the fixed issue in commit
- Send a pull request for the original project
- Comment on the original issue that you have implemented a fix for it
Add-on is distributed under Apache License 2.0. For license terms, see LICENSE.txt.
ViewPortExtension is written by Tatu Lund
Here is a simple example on how to try out the add-on component:
<...>
For a more comprehensive example, see src/test/java/org/vaadin/template/demo/DemoUI.java
The method returns true/false status about component being in visible viewport or not.
Event is fired when component is going out or in viewport, can be observed with ViewPortStatusChangedListener
ViewPortExtension has JavaDoc