Hello,
I have written an application that allows add/retrieve/delete to the linked list and in the same time, update in the MFC dialog's combo box.
It has no problem deleting the first item in the combo box, but whenever I tried to delete the subsequent item, it shows in the combo box that the item is deleted, but in reality, only the first item in the linked list is deleted. It seems to delete the first item ONLY.
the code for the Add/Retrieve/Delete
int CMainFrame::Add(AO_info *NewItem)
{
AO_info *new_item = new AO_info;
new_item = NewItem;
new_item->AO_Next = AO_Head;
AO_Head = new_item;
// get linked list size
int size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
// increment size
size++;
// set linked list size
((CMainFrame*)AfxGetMainWnd())->SetAO_Size(size);
return size;
}
AO_info *CMainFrame::Retrieve(int position)
{
AO_info *Current = AO_Head;
// get linked list size
int size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
for (int i = size - 1; i > position && Current != NULL; i--)
{
Current = Current->AO_Next;
}
return Current;
}
bool CMainFrame::Delete(int position)
{
// get linked list size
int size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
if (Retrieve(position) == NULL)
return false;
else if (position == 0)
{
AO_info *current = Retrieve(1);
current->AO_Next = NULL;
size--;
// set linked list size
((CMainFrame*)AfxGetMainWnd())->SetAO_Size(size);
delete current;
return true;
}
else
{
Retrieve(position + 1)->AO_Next = Retrieve(position - 1);
// decrement size
size--;
// set linked list
((CMainFrame*)AfxGetMainWnd())->SetAO_Size(size);
return true;
}
}
here's the code that manage the dialog's GUI.
BOOL CMap0::OnInitDialog()
{
CDialog::OnInitDialog();
// TODO: Add extra initialization here
// retrieve linked list size
unsigned int size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
m_numcount = size;
if (size > 0)
{
for (int i = 0; i < size; i++)
{
AO_info* one = ((CMainFrame*)AfxGetMainWnd())->Retrieve(i);
// insert the item to the end of the list
m_AO_range0.InsertString(-1, one->start_stop_azimuth);
}
}
UpdateData(FALSE);
return TRUE; // return TRUE unless you set the focus to a control
// EXCEPTION: OCX Property Pages should return FALSE
}
void CMap0::OnAoadd()
{
// TODO: Add your control notification handler code here
// add to the linked list
AO_info *NewItem = new AO_info;
CString range;
char *range_local;
range = "";
strcpy(NewItem->start_stop_azimuth, range);
UpdateData(TRUE);
NewItem->start_azimuth = m_AO_StartAzimuth;
NewItem->stop_azimuth = m_AO_StopAzimuth;
sprintf(range_local, "%f to %f", m_AO_StartAzimuth, m_AO_StopAzimuth);
range = range_local;
strcpy(NewItem->start_stop_azimuth, range);
int size = ((CMainFrame*)AfxGetMainWnd())->Add(NewItem);
m_AO_range0.InsertString(-1, range);
m_M0DataValid = range + " added";
m_numcount = size;
UpdateData(FALSE);
return;
}
void CMap0::OnAodelete()
{
// TODO: Add your control notification handler code here
int pos = m_AO_range0.GetCurSel();
int size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
if (size == 0)
{
m_M0DataValid = "There is no data to be deleted!";
UpdateData(FALSE);
}
else
{
((CMainFrame*)AfxGetMainWnd())->Delete(pos);
m_M0DataValid = "Entry deleted!";
UpdateData(FALSE);
size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
// update the new size
m_numcount = size;
// delete string in combo box
m_AO_range0.DeleteString(pos);
// clear the other boxes
m_AO_StartAzimuth = 0;
m_AO_StopAzimuth = 0;
UpdateData(FALSE);
}
}
void CMap0::OnAoview()
{
// TODO: Add your control notification handler code here
int size = ((CMainFrame*)AfxGetMainWnd())->GetAO_Size();
int pos = m_AO_range0.GetCurSel();
if (pos < size)
{
AO_info* one = ((CMainFrame*)AfxGetMainWnd())->Retrieve(pos);
m_AO_StartAzimuth = one->start_azimuth;
m_AO_StopAzimuth = one->stop_azimuth;
UpdateData(FALSE);
}
}
I have tired numerous way to modify the Add/Retrieve/Delete function that are called in the CMainFrame but it always deleting the first item added to the list ONLY.
Please help! I am very desperate now... Thank you so much.
03-Apr-2008, 06:24
2nd Week of IA Training by crystalattice
Similar Threads
