How does a ZK Component work

A component and a widget work hand in hand to deliver a rich UI experience to a user. The widget traps the user activity and sends an appropriate request to the component. The component then interacts with the developer’s application which would respond appropriately telling when the widget should update. This interaction is demonstrated in the following diagram.

For example, when an application invokes the setLabel method to change the label of a button component, the setLabel method of corresponding button widget (aka., peer widget) will be invoked at the client to change the visual appearance (as shown below).

When the user clicks the button widget, the onClick event will be sent back to the server and notify the application (as demonstrated below).

In addition to manipulate a component at the server, it is also possible to control a widget at the client. For example, an application may hide or change the order of grid columns at the client, while the application running at the server handles the reloading of the grid’s content. This technique is called Server+client fusion. It can be used to improve responsiveness and reduce network traffic.