How can I remove a QPushButton?

[Claudia Neumann]

Hi all,

I would like to remove Buttons. How can I do that?
removeItem() and removeWidget() won't do it. A few months ago I could set
oP1 := NIL. That won't do either.

-----------------
PROCEDURE Main()
memvar oLay, oW, oP0, oP1, oP2, oP3, oP4, oP5, oP6


oW := QWidget()
oW:setWindowTitle( "Finestra di Giovanni" )
oW:resize( 400, 100 )

oP0 := QPushButton()
oP0:setText( "OK 1" )

oP1 := QPushButton()
oP1:setText( "OK 2" )
oP1:connect ( " clicked ()", { | | removeButtons( 1 )} )

oP2 := QPushButton()
oP2:setText( "OK 3" )
oP2:connect ( " clicked ()", { | | removeButtons( 2 )} )

oP3 := QPushButton()
oP3:setText( "OK 4" )
oP3:connect ( " clicked ()", { | | removeButtons( 3 )} )

oP4 := QPushButton()
oP4:setText( "OK 5" )
oP4:connect ( " clicked ()", { | | removeButtons( 4 )} )

oP5 := QPushButton()
oP5:setText( "OK 6" )
oP5:connect ( " clicked ()", { | | removeButtons( 5 )} )

oP6 := QPushButton()
oP6:setText( "OK 7" )
oP6:connect ( " clicked ()", { | | removeButtons( 6 )} )

oLay := QHBoxLayout( oW )
oLay:addWidget( oP0 )
oLay:addWidget( oP1 )
oLay:addWidget( oP2 )
oLay:addWidget( oP3 )
oLay:addWidget( oP4 )
oLay:addWidget( oP5 )
oLay:addWidget( oP6 )
oW:show()

QApplication():exec()

RETURN


Function removeButtons( nnr )
memvar oLay, oW, oP0, oP1, oP2, oP3, oP4, oP5, oP6

do case
case nnr == 1
oP1:removeWidget()
case nnr == 2
oP2:removeWidget()
case nnr == 3
oP3:removeWidget()
case nnr == 4
oP4:removeWidget()
case nnr == 5
oP5:removeWidget()
case nnr == 6
oP6:removeWidget()
endcase

return .t.
------------------

Best regards

Claudia

[Giovanni Di Maria]

Hi Claudia

you can use  the property "visible" as follow:

oButton1:Connect( "clicked()", { || oButton2:setVisible ( .F. ) } )

In this example, if you press the button 1, the button 2 desappears.

Regards.

Giovanni

P.S.

This will be a topic for HBQT Tutorial.

Giovanni

[Pritpal Bedi]

Hi

> Function removeButtons( nnr )
> memvar oLay, oW, oP0, oP1, oP2, oP3, oP4, oP5, oP6
>
> do case
> case nnr == 1
>  oP1:removeWidget()

I assume you want to remove the button permanently.

If YES, then
oP1:setParent( QWidget() )

if NO
Follow Giovani's reply.

Pritpal Bedi

[Claudia Neumann]

Hi Pritpal, hi Giovanni,

thanks for the advice.

Am Sonntag Juli 15 2012 schrieb Pritpal Bedi:
> Hi
>
> > Function removeButtons( nnr )
> > memvar oLay, oW, oP0, oP1, oP2, oP3, oP4, oP5, oP6
> >
> > do case
> > case nnr == 1
> > oP1:removeWidget()
>
> I assume you want to remove the button permanently.
>
> If YES, then
> oP1:setParent( QWidget() )

I would like to remove the button permanently. But I get segmentation fault.

>
> if NO
> Follow Giovani's reply.

Okay, this does it. But will there be problems with invisible Widgets?

Test code that functions:

PROCEDURE Main()

memvar oLay, oW, oP0, oP1, oP2, oP3, oP4, oP5, oP6

oW := QWidget()
oW:setWindowTitle( "Finestra di Giovanni" )
oW:resize( 400, 100 )

oP0 := QPushButton()
oP0:setText( "OK 1" )

oP0:connect ( " clicked ()", { | | removeButtons( 0 )} )

Function removeButtons( nnr )
memvar oLay, oW, oP0, oP1, oP2, oP3, oP4, oP5, oP6

do case

case nnr == 0
oP0:setVisible(.F.)
case nnr == 1
oP1:setVisible(.F.)
case nnr == 2
oP2:setVisible(.F.)
case nnr == 3
oP3:setVisible(.F.)
case nnr == 4
oP4:setVisible(.F.)
case nnr == 5
oP5:setVisible(.F.)
case nnr == 6
oP6:setVisible(.F.)
endcase

return .t.


Best regards

Claudia

[Pritpal Bedi]

Hi

> > If YES, then
> >    oP1:setParent( QWidget() )
>
> I would like to remove the button permanently. But I get segmentation fault.
>

Sorry Forget:

oLay:removeWidget( oP0 )
oP0:setParent( QWidget() )


Please inform if it works. Have no time to build.

Pritpal Bedi

[vszakats]

Is a GPF still normal with HBQT?

-- Viktor

[Pritpal Bedi]

Hi

> Is a GPF still normal with HBQT?

Do not know yet.
In a couple of hours I will try to build above
example to get what is happening. May be
it gives another insight why HbIDE is crashing
on exit if compiled with VS2010 and Qt 4.6
throught 4.8.1. With mingw everything is fine.

Pritpal Bedi

[Claudia Neumann]

Hi Pritpal,

Am Sonntag Juli 15 2012 schrieb Pritpal Bedi:

> Hi
>
> > > If YES, then
> > > oP1:setParent( QWidget() )
> >
> > I would like to remove the button permanently. But I get segmentation
> > fault.
>
> Sorry Forget:
>
> oLay:removeWidget( oP0 )
> oP0:setParent( QWidget() )
>
>
> Please inform if it works. Have no time to build.

Compiled on WinXP with MinGW with QT 4.8.2 it works.

Compiled on Linux Debian with gcc 4.3.5 and QT 4.6.3 I get segmentation fault.

Best regards

Claudia

[Claudia Neumann]

Hi Pritpal,

Am Sonntag Juli 15 2012 schrieb Pritpal Bedi:

No, it doesn't work: again segmentation fault.

Best regards

Claudia