C / C++ / MFC

1-Nov-07 2:54

Can anybody tell me how to clear the combo box in the OnEditChange Function.

what i want is : i am searching and loading the ComboBox with values from the database based on the string i give in the ComboBox. So as the string changes i need new values to be loaded in the ComboBox. What is happening now is if i change the string,the ComboBox is loaded with values of the new string and the old string.I dont need the previous values.i tried RESETCONTENT function within the OnEditChange Function.But it didnt work.

thanks in advance

David Crow1-Nov-07 2:59

1-Nov-07 2:59

philiptabraham wrote:
Can anybody tell me how to clear the combo box in the OnEditChange Function.

See here.

philiptabraham wrote:
i tried RESETCONTENT function within the OnEditChange Function.But it didnt work.

Why not? What happened? Be specific.

"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman

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philiptabraham1-Nov-07 3:09

1-Nov-07 3:09

when i give the function it is always getting reseted.

ex:i need to retrieve all the values from the database starting with 'p'.So ill give 'p' in the comboBox and the Corresponding values loaded into the combobox.But latter if i want retrieve all the values from the database starting with 'po', then it is listing all the datas starting with 'p' and 'po'.

What i have done is in the EditChangeFunction i am fetching the user entered value from the combobox say 'p' create the query and call the database function.The Result from the database are stord in an array and this array is loaded into the ComboBox Using AddString.

David Crow1-Nov-07 3:12

1-Nov-07 3:12

philiptabraham wrote:
when i give the function it is always getting reseted.

Last time I checked, that is exactly what the CB_RESETCONTENT message is supposed to do.

philiptabraham1-Nov-07 3:24

1-Nov-07 3:24

this is a sample code that i have done

OnEditChange()
{
m_aa.AddString("xxx");//m_aa is the variable of my combobox of Type CComboBox
m_aa.AddString("YYY");
m_aa.RESETCONTENT();//will not allow me to edit the comboBox ,it will get reset
}
whati nedd is ,whenever i make a change in the combobox only xxx and yyy should be displayed in the combobox list.

what is happening now is whenever i make or edit the combobox the number of time the data displaying is doubled

chandu0041-Nov-07 3:27

1-Nov-07 3:27

here, you are adding the string and then resetting the content.
got it?

David Crow1-Nov-07 3:32

1-Nov-07 3:32

I'd hazard a guess and say that you that you might need to remove old items from the combobox before adding new ones? Wink | ;)

philiptabraham1-Nov-07 3:37

1-Nov-07 3:37

i tried that also but its not getting it removed completely.

what i tried is: On the second time before adding new string ill get the count and within the loop i tried to delete the string.But every thing is not getting deleted

David Crow1-Nov-07 3:50

1-Nov-07 3:50

philiptabraham wrote:
On the second time before adding new string ill get the count and within the loop i tried to delete the string.But every thing is not getting deleted

Probably because you are removing from the top-down rather than from the bottom-up. Why are you not removing them all at once rather than one at a time?

chandu0041-Nov-07 3:15

1-Nov-07 3:15

have you used
combovariable.ResetContent();
before calling your query?

--------------------------------------------
Suggestion to the members:
Please prefix your main thread subject with [SOLVED] if it is solved.
thanks.
chandu.

philiptabraham1-Nov-07 3:32

1-Nov-07 3:32

what is happening is if i give restContent it will reset it after each character i enter in the combobox. For example if i type p the value is reseted where as i want to search a string for 'po'.

philiptabraham1-Nov-07 3:34

1-Nov-07 3:34

i need to retrieve all the values from the database starting with 'p'.So ill give 'p' in the comboBox and the Corresponding values loaded into the combobox.But latter if i want retrieve all the values from the database starting with 'po', then it is listing all the datas starting with 'p' and 'po'.

if i give RESTCONTENT after writing p, it will get reseted. I wont be able to search for strings with 2 or 3 letters

chandu0041-Nov-07 3:41

1-Nov-07 3:41

now i got your concept.
you mean, you are dealing the on edit change event of the combo box it self.
if so, do one thing.
1.first, before calling the query, preserve the string available in the combobox, in a temporarystring, by using getdlgitemtext().
2.then reset your content.
3.then call your query and upload them into the combo using addstring.
4.then using setdlgitemtext set the temporary string to the dialog.

but here, iam not sure about the cursor position. you have to check it out.

lets see if any body suggests a better technique.

philiptabraham1-Nov-07 3:55

1-Nov-07 3:55

thank a lot...

chandu0041-Nov-07 3:58

how to add an backrground image in a form?

1-Nov-07 3:58

wait a minute!!!
now what happened to your cursor position?
and what about my suggestion?(see down) Big Grin | :-D

;)

--------------------------------------------
Suggestion to the members:
Please prefix your main thread subject with [SOLVED] if it is solved.
thanks.
chandu.

panthal1-Nov-07 2:51

panthal

1-Nov-07 2:51

hi,
i'am trying to add an image as background of a form.

but i don't know , how to add?
if you know please tell me

thanks
panthal

Re: how to add an backrground image in dialog?

chandu0041-Nov-07 2:54

Re: how to add an backrground image in a form?

1-Nov-07 2:54

use picture control.

David Crow1-Nov-07 2:56

Re: how to add an backrground image in a form?

1-Nov-07 2:56

panthal wrote:
if you know please tell me

See here.

Hamid_RT1-Nov-07 5:56

Hamid_RT

1-Nov-07 5:56

If you want to show image on the forum you can use of WM_ERASEBKGN with CImage class like this

#include "AtlImage.h"

CImage m_Image;
m_Image.Load("c:\\123.jpg");

BOOL CdddDlg::OnEraseBkgnd(CDC* pDC)
{

ppp.BitBlt(pDC->m_hDC,0,0);
return TRUE;
}

This is a minumum code for show image on the forum.

But if you want to use of a control to show an image you can use of Static control you must insert Static control of Toolbar on the forum and use of this code

CImage m_Image;
m_Image.Load("c:\\1234.jpg");
m_Static.SetBitmap(m_Image.Detach());

unable to scroll the dialog using the slider in the scrol bar

chandu0041-Nov-07 2:21