Creative Tutorial for Kids

Now it’s time to fill in the functions you just created. Refer to Listing 3.2 as you read through this section. To begin with, try and compile your project. One thing you’ll notice is that the compiler complains that NULL is undefined. One great addition to Visual C++ .NET is that when you’re adding member variables to a class like we did earlier, the generated code also includes class initializers for these variables. In this case, because we declared pointers, the generated code set these variables to NULL. However, it didn’t add the appropriate #include statement. To fix this problem, include the header file stdlib.h at the top of the HelloNETForm.cpp file. Your program should now compile with zero errors and zero warnings.

Begin by filling in the constructor code. Because the member variables you added are simply pointers, you need to create the objects before you can use them. Therefore, create the form control container member variable (m_pComponents) by using the C++ keyword new. The remaining line in the constructor calls the InitForm function.

In the InitForm() function, create the three controls, one by one, and set the properties appropriately. After all the controls are created, they are added to the form with the Form::Controls->Add() method. The order in which the controls are added has an effect on the tab order if the tab order isn’t specified for the controls. In this case, it is specified and therefore doesn’t matter.

Taken From: SAMS-Tech Yourself MS Visual C++.NET in 24 Hours

Filed under:
Uncategorized by admin