>Hi Fabio,
>It looks like the Click event for CommandButton, Checkbox, combobox, listbox, optiongroup,... by design, triggers the Valid event. Valid, normally fires when a control loses focus, but because when you click on a control focus must stay on the control, when fires the second time.

>However, if the CommandButton has the focus, Click doesn't trigger Valid...

??? sure ???

ACTIVATE WINDOW "debug Output"
SET EVENTLIST TO Click,Valid,When,Message,InteractiveChange
SET EVENTTRACKING ON

loForm = createobject('zForm')
loForm.show

FOR k=1 TO 20
	CHRSAW(0.2)
	KEYBOARD  '{SPACEBAR}' PLAIN CLEAR
	DOEVENTS
NEXT



define class zForm as form
	Caption = "Click on When button"
	Name = "Form1"
	Autocenter = .T.
	Width = 360
	Height = 150
	visible = .t.

	ADD OBJECT text1 AS textbox WITH ;
		Height = 23, ;
		Left = 20, ;
		Width = 80, ;
		TabIndex = 2, ;
		Top = 10, ;
		Name = "Text1", ;
		enabled = .F.,;
		value = 0
	ADD OBJECT command1 AS COMMANDBUTTON WITH ;
		Top = 10, ;
		Left = 140, ;
		Height = 27, ;
		Width = 120, ;
		Caption = "When", ;
		TabIndex = 1, ;
		Name = "Command1"

	ADD OBJECT label1 AS label WITH ;
		top = 44, ;
		left = 20, ;
		width = 250, ;
		wordwrap = .T., ;
		autosize = .t., ;
		Caption = "When event fires twice when the button does not have focus before click!!?"
	ADD OBJECT label2 AS label WITH ;
		top = 84, ;
		left = 20, ;
		width = 250, ;
		wordwrap = .T., ;
		autosize = .t., ;
		Caption = "When event fires once when the button has focus before click!!?"

	PROCEDURE command1.Valid
		RETURN .F.	&& this is ignored
	ENDPROC

* workaround
*		PROCEDURE command1.Click
*			NODEFAULT
*		ENDPROC

	PROCEDURE command1.valid
		thisform.text1.value = thisform.text1.value + 1
	ENDPROC

	PROCEDURE load
		ADDPROPERTY(this,"lock",this)
ENDDEFINE