UserGuide

Web Timer

From Xojo Documentation

The Timer executes some code once or repeatedly after a period of time has passed.

Timer is covered in more detail in the UserGuide:Timers topic.

The Web Timer is very similar to the standard Timer control. The important difference is that the Web Timer can be server-side or client side meaning that it would be part of the webpage it's on.

A Web Timer can be used to update controls on the page, for example. A standard Timer control will only execute server-side, so it cannot contact the client.

Events

Run - The Run event is called when the Timer period is reached.

Properties

RunMode - Indicates if the Timer is Off, Single or Multiple.

Period - The number of milliseconds between calls to the Action event.

Methods

Reset - Call this to reset and restart the Timer.

Usage

The Web Timer provides the same functionality as the Desktop Timer control. This example updates the value on a label (SecondsPassedLabel) on the web page using the WebTimer. This code in the WebTimer updates the label:

SecondsPassedLabel.Value = Str(SecondsPassedLabel.Value.ToInteger + 1)

You can also add a button to start and stop the timer. This code is in a Button's Pressed event:

If Me.Caption = "Start" Then
Timer1.Mode = WebTimer.RunModes.Multiple
Me.Caption = "Stop" // button caption
Else
SecondsPassedLabel.Value = "0"
Timer1.Mode = WebTimer.RunModes.Off // Turn off the timer
Me.Caption = "Start"
End If

Example Projects

These project demonstrate ways that a Web Timer is used to update the UI:

  • Examples/Web/Controls/Progress
  • Examples/Web/Controls/TimerExample
  • Examples/Web/Controls/ThreadProgress

See Also

WebTimer class