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

# TCustomCheckListBox.ClickCheck

Performs actions needed when a value in the control is about to change.

## Declaration

Source position: checklst.pas line 68

`protected procedure TCustomCheckListBox.ClickCheck; virtual;`

## Description

ClickCheck is a method used to perform actions needed when a value in the control is about to change.

ClickCheck signals the OnClickCheck event handler (when assigned) using the current class instance as the object for the event notification. Use OnClickCheck to implement the actions needed when the control has been changed.

ClickCheck is called when the LM_CHANGED message is handled for the control, and occurs prior to calling the ItemClick method where the OnItemClick event handler is signalled.

ClickCheck is also called from the KeyDown method when the Space key has been pressed while the control has focus. It is called after ItemIndex has been range adjusted (when needed) and the inherited Click method is called. In addition, the value in Checked has already been toggled before the method is called. ClickCheck is not called for the keystroke when the check box item in ItemIndex is not enabled.

## See also

TCustomCheckListBox.OnClickCheck |  | Event handler signalled when a check box in the control has been changed.
TCustomCheckListBox.ItemClick |  | Deprecated. Performs actions when the specified check box has been changed using the mouse or the keyboard.
TCustomCheckListBox.OnItemClick |  | Deprecated. Event handler signalled when the check box state for a specific item has been changed.
TCustomCheckListBox.KeyDown |  | Handles key down messages for the control.
TCustomCheckListBox.Checked |  | Provides indexed access to the Boolean Checked or Unchecked state for Items in the control.
TCustomCheckListBox.ItemEnabled |  | Provides indexed access to the enabled state for Items in the control.