[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'Dialogs' (#lcl)

# TCustomTaskDialog.OnTimer

Event handler signalled when the interval for the timer on the dialog has elapsed.

## Declaration

Source position: dialogs.pp line 852

`public property TCustomTaskDialog.OnTimer : TTaskDlgTimerEvent read FOnTimer write FOnTimer;`

## Description

OnTimer is a TTaskDlgTimerEvent property with the event handler signalled when the interval for the timer in the task dialog has elapsed. It is signalled (when assigned) from the DoOnTimer method and receives values for the object instance, tick count since the timer was started, and a reset flag.

For the native Windows Task Dialog API, it occurs when the TDN_TIMER notification is handled in the callback procedure for the dialog. For platforms which use an emulated task dialog, it occurs when the handler routine for the internal TTimer instance in TLCLTaskDialog has elapsed. The timer interval is 200ms.

An application can implement and assign a handler using the signature in TTaskDlgTimerEvent to perform actions needed when the notification occurs in the class instance.

## Version info

Added in LCL version 4.0.