Handling Complex Rules in in GUI applciations (C++ or C#)
- by Canacourse
Im working on a dialog box in which several rules must be satisfied before the OK button is enabled.
Currently any action on the page such as entering data or selecting an item from a drop down list (amongst other things) calls a single function called ProcessEvent() - this function handles all logic and either enables or disables the OK button.
My problem is I finding it difficult making the rules concise and understandable.
Some of the rules can be negated by another action on the dialog and I have now ended up with if else statements all over the place or which are difficult to read and follow & extend.
The code below is a simplification of the problem but demonstrates it well. How do I handle this problem better (If its Possible)
bool CWorkstation::ProcessEvent(void)
{
UpdateData();
CharCount = GetDlgItemInt(IDC_CharCount, NULL, FALSE); //get latest
if ( IsDlgButtonChecked(IDC_USEDBNAME))
{
if (!IsDlgButtonChecked(IDC_MAXDBNAME))
{
EnableNext(TRUE);
}
}
if (IsDlgButtonChecked(IDC_MAXDBNAME) && CharCount)
{
if (IsDlgButtonChecked(IDC_USEXMLNAME))
{
if ( PrefixName.IsEmpty() )
{
EnableNext(FALSE);
}
else
{
EnableNext(TRUE);
}
}
}
if (IsDlgButtonChecked(IDC_USEXMLNAME) && PrefixName.GetLength() > 1)
{
EnableNext(TRUE);
}
if ( IsDlgButtonChecked(IDC_WSAUTONAME) || IsDlgButtonChecked(IDC_RENAMEIFDUP))
{
// TRACE("IDC_WSAUTONAME is Checked\n");
if ( IsDlgButtonChecked(IDC_USEXMLNAME) && PrefixName.GetLength() > 1 )
{
if ( IsDlgButtonChecked(IDC_IDC_USESHORTNAME) )
{
EnableNext(TRUE);
}
else if ( IsDlgButtonChecked(IDC_USELONGNAME) )
{
EnableNext(TRUE);
}
else
{
EnableNext(FALSE);
}
}
if ( !IsDlgButtonChecked(IDC_USEPREFIX) )
{
if ( IsDlgButtonChecked(IDC_IDC_USESHORTNAME) || IsDlgButtonChecked(IDC_USELONGNAME) )
{
EnableNext(TRUE);
}
}
return false;
}
}
