CListCtrl Column-wise dblclick handling

Hi,

I am new VC++, iam working on a CListCtrl which has two columns. I need to handle NM_DBLCLICK separately for each of the two columns. The first column contains item names while the second contains their corresponding prices. If the user double clicks the item name column, the items name is appended to an edit box, similarly if the user double clicks the item price its price is appended to the editbox.

how can this be done?

thanks in advance :)

Try to use GetMessagePos to get cursor coordinates and CListCtrl::SubItemHitTest to obtain list control column

Thanks for the response Victor, heres what the code for the right click looks like:

Code:

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void MyProject::OnRclickHistList(NMHDR* pNMHDR, LRESULT* pResult)
{

        DWORD dwPos = GetMessagePos();
        CPoint pt( GET_X_LPARAM( dwPos ), GET_Y_LPARAM( dwPos ) ), spt;
        spt = pt;
        ScreenToClient( &spt );

        //Check if list is empty
        if( GetItemCount() == 0 )
                iMenuType = 0;
        //list not empty but no item clicked
        //check if any item was clicked
        //fill up LVHITTESTINFO and call SubItemHitTest
        LVHITTESTINFO test;
        test.pt                = pt;
        test.flags        = LVHT_ONITEM ;

        int retval        = SubItemHitTest(&test);

        *pResult = 0;
}

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the trouble is that retval is always -1 regardless of whether i click on any item on the list or outside it.

Another issue iam facing is that first row of the list control doesn't respond to any Events. I have NM_DBLCLICK and NM_RCLICK message maps, but nothing works on the first row.

What message are you trying to handle: NM_DBLCLICK or right mouse click?
If the latter - then use WM_CONTEXTMENU instead!

Hi Victor,

Sorry i got a little mixed up, I have to handle both RClick and DBLClick. I tried ON_WM_CONTEXTMENU for rclick - and got the following error:

Code:

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error C2440: 'static_cast' : cannot convert from 'void (__thiscall MyProject::* )(CWnd *,CPoint,int)' to 'void (__thiscall CWnd::* )(CWnd *,CPoint)'
        Cast from base to derived requires dynamic_cast or static_cast

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Iam new to this, i've been calling OnContextMenu from the function for handling right clicks, for using WM_CONTEXTMENU...i added ON_WM_CONTEXTMENU to the message map and commented out the code handling the right click except for the OnContextMenu(...) function. Is this the right way? Another thing is that I have derived a class from CListCtrl and am using an object of that class to add a CListCtrl to the dialog at runtime.

Quote:

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Originally Posted by austinium

Hi Victor,

Sorry i got a little mixed up, I have to handle both RClick and DBLClick. I tried ON_WM_CONTEXTMENU for rclick - and got the following error:

Code:

---

error C2440: 'static_cast' : cannot convert from 'void (__thiscall MyProject::* )(CWnd *,CPoint,int)' to 'void (__thiscall CWnd::* )(CWnd *,CPoint)'
        Cast from base to derived requires dynamic_cast or static_cast

---

---

You should use class Wizard to add message handlers! Don't do it by hand!

Quote:

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Originally Posted by austinium

Iam new to this, i've been calling OnContextMenu from the function for handling right clicks, ...

---

No, it is wrong!
OnContextMenu handler must be called from the framework, not from your code!

hi,

ok ... kinda messed up here haven't i! Thank you so much Victor for helping out :)

Heres the situation:
I have a class that derives CListCtrl (All the event handling goes in here)
I create an object of this class to create a listview at runtime.
The list view is a two column setup.
The user can right click to bring up a context menu (there are different types of these menu, depending on if the user has clicked on empty space in the list or on an item in the list)
The user can also dbl click to perform separate actions depending on which column he has clicked.
I cannot use the wizard to add event handling code because the List is created at runtime( it has to be - specification :( )

Heres what i have been doing...
I register a handler for NM_RCLICK and call OnContextMenu from the handler. - this is wrong, i havent been able to get WM_CONTEXTMENU to work.
for DBL_CLICK, i registered NM_DBLCLICK it works fine, but i need to find a way to differentiate between the items of the two columns of the list. May be i could store items from each list in a CStringArray and use GetMessagePos ,CListCtrl::SubItemHitTest to match from the arrays to figure out which column the item dbl clicked belongs to...i'll try that.

I am not sure about the right click though, for some strange reason i get an error on using ON_WM_CONTEXTMENU and even if i stick to my method(which is wrong as u pointed out) the very first row doesn't respond to clicks (both rclicks and dblclicks).

thanks for helping out so far Victor, any ideas about this?

thanks again :)

Quote:

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Originally Posted by austinium

... I cannot use the wizard to add event handling code because the List is created at runtime( it has to be - specification :( )

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Why "at runtime"? :confused:
Just create it in resource editor and make it invisible (hide it).
Then add the control member variamle of your derived from CListCtrl class type.
Then when you will need "to create" this control - just show it! (CWnd::ShowWindow)

You CAN use the wizard. Just locate your derived class in the class wizard, add handler for WM_CONTEXTMENU.

Thanks for helping out VictorN , hoxsiew. I used SubItemHitTest for extracting item text. based it on code from MSDN's example for the function. I will change to WM_CONTEXTMENU as soon as i get some other issues fixed. for now the current setup works.