Reminder in GWT

Question

I am doing an project on Java and GWT and stuck in one part I want to create a reminder that is like user enters date and time and at that time a pop up should be displayed reminding user of his event. Can anyone suggest me any approach towards achieving this.

When I googled for the solution i found some stuff related to timers in GWT but I guess timer has method schedule() which takes milliseconds as parameter but converting date and time into milliseconds doesn't seem the solution so any other alternative is highly appreciated.

Answer 1

You can't handle it with only timers. Seems that you need to implement some server side logic to achieve this.

1. User select time and date for event on client -> call to server to store it somewhere (could be simple RPC or Ajax call)

2. Notifying the user could be achieved by several ways:

   • Simple polling - ask server from client what events happened since last check every N (let't say 10) seconds, using Ajax calls. Server needs to compare current time and send events list back to the client

   • Long poll or Hidden Iframe to be used for pushing the events to the client - more complex, but also could be implemented

You can also take a look at GwtEventService to manage your events between server and client.

Finally your logic stays simple - client needs to listen from the server about happened events and to show pop up dialog in the handler.