Re: Question about Callback

[Rudolfo Pinewood <rudolfo pinewood googlemail com>]

Hi,
I think I should post some more lines of "my" code... as a sidenote: I 
did not do much c++ programming before, neither anything with GTK.

Here is a link to what I have (actually):
http://ufoai.svn.sourceforge.net/viewvc/ufoai/ufoai/trunk/src/tools/radiant/radiant/sidebar/surfaceinspector.cpp?revision=21479&view=markup&pathrev=21796

I wanted to enhance ApplyFlags function (starting at line 957) to get an 
additional parameter regarding the button/nonModalEntry that was 
changed. For this I defined another class as following:

class ChangeIndicator
{
        public:
		const unsigned int m_surfaceBtnMask; /**< indicator about changed 
surface button */
		const unsigned int m_contentBtnMask; /**< indicator about changed 
content button */
                const bool m_valueChanged; /**< indicator, that value field was changed */
		ChangeIndicator (const unsigned int surfaceBtnMask, const unsigned int 
contentBtnMask, const bool valueChanged) :
			m_surfaceBtnMask(surfaceBtnMask), m_contentBtnMask(contentBtnMask), 
m_valueChanged(valueChanged)
                {
                }
};

for m_ValueEntry I would like to use ChangeIndicator(0, 0, true), for 
the buttons something like ChangeIndicator(1<<btnid,0,false)

My problem is that I don't know where to put these values, as something 
like ApplyFlagsCaller(*this, ChangeIndicator(1 << id, 0, false)))
is not working (obviously because Membercaller only has a Constructor 
with an Environment).

Any help is welcome.
Greetings,
Christoph Hartwig

On Sun, 11 Jan 2009 12:42:41 +0100
Rudolfo Pinewood <rudolfo pinewood googlemail com> wrote:

> I have several togglebuttons, that are all registered to call one
> specific function (ApplyFlags). In this function I actually don't know
> which button was activated.
>
> My attempt was giving each button/callback an additional parameter that
> should be passed to my ApplyFlags function.

You yet have the caller widget in ApplyFlags(). If you're using
g_signal_connect_swapped(), just use the second arg:

void ApplyFlags(gpointer your_data, GtkWidget *button)

Ciao
--
Nicola


Rudolfo Pinewood schrieb:
> Hi,
> I have a question regarding Callback functions for Toggle buttons.
>
> I have several togglebuttons, that are all registered to call one
> specific function (ApplyFlags). In this function I actually don't know
> which button was activated.
>
> My attempt was giving each button/callback an additional parameter that
> should be passed to my ApplyFlags function.
>
> However I was not able to do so - MemberCaller1 seems to fit (regarding
> the "call one function with one parameter") but I did not manage to get
> my parameter into that Callback in
> g_signal_connect_swapped(G_OBJECT(button), "toggled", 
> G_CALLBACK(callback.getThunk()), callback.getEnvironment()).
>
> How could this be done?
> Thanks in advance
> Christoph Hartwig