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Prof-UIS 2.80

I like create assertion of value in CExtGridCellUpDown. After searching for information about this I found thread "Setting a range to numeric cells" where you propose overriding of OnQueryEnabledDecrement() and OnQueryEnabledIncrement().

Next simple class has been created:

class CMyNumericClass : public CExtGridCellUpDown
{
public:

    long minvalue;
    long maxvalue;

    virtual bool OnQueryEnabledDecrement() const;
    virtual bool OnQueryEnabledIncrement() const;
};

bool CMyNumericClass::OnQueryEnabledIncrement() const
{
    ASSERT_VALID( this );
    if( intVal >= maxvalue )
        return false;
    return true;
}

bool CMyNumericClass::OnQueryEnabledDecrement() const
{
    ASSERT_VALID( this );
    if( intVal <= minvalue )
        return false;
    return true;
}

so it methods don`t call when data has been changed(by pressing to the Up/Down button of component or Copy/Paste way). Where mistake?

thanks

You need some more additions to make it work.
in .h file:

class CMyNumericClass : public CExtGridCellUpDown
{
public:
	DECLARE_SERIAL( CMyNumericClass );
	IMPLEMENT_ExtGridCell_Clone( CMyNumericClass, CExtGridCellUpDown);

	CMyNumericClass CExtGridDataProvider * pDP = NULL);
	virtual void Assign( const CExtGridCell & other );
public:

    long minvalue;
    long maxvalue;

    virtual bool OnQueryEnabledDecrement() const;
    virtual bool OnQueryEnabledIncrement() const;
};

In .cpp file:

...
#include "Somefile.h"
 
IMPLEMENT_SERIAL( CMyNumericClass, CExtGridCellUpDown, VERSIONABLE_SCHEMA|1 );
 
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
...
CMyNumericClass::CMyNumericClass( CExtGridDataProvider * pDP /* = NULL */ )
	: CExtGridCellUpDown( pDP )
	, minvalue(0) // or something else
	, maxvalue(0) // or something else
{
}
 
void CMyNumericClass::Assign( const CExtGridCell & other )
{
	ASSERT_VALID( this );
	CExtGridCellUpDown::Assign( other );
	CMyNumericClass *pCell = DYNAMIC_DOWNCAST(CMyNumericClass, (&other));
	if ( pCell != NULL ) {
		minvalue = pCell->minvalue;
		maxvalue = pCell->maxvalue;
	}
}
 
bool CMyNumericClass::OnQueryEnabledIncrement() const
{
	ASSERT_VALID( this );
	if( intVal >= maxvalue )
		return false;
	return true;
}
 
bool CMyNumericClass::OnQueryEnabledDecrement() const
{
	ASSERT_VALID( this );
	if( intVal <= minvalue )
		return false;
	return true;
}

It’s important to have the Assign method implemented and to have IMPLEMENT_SERIAL macro above #ifdef _DEBUG block.

When using the cell for the first time ( filling it ), you need to call GridCellGet(nColNo, nRowNo, 0, 0, RUNTIME_CLASS(CMyNumericClass)); to make sure your class is used.