Creating Your First Real Program

From the main menu, select File, New Application. A new project will be created. Let's save this project by selecting File, Save Project As from the main menu.

Give the form's source code a name. Change the default Unit1.cpp to Mainform.cpp .

After saving the form's source code, the project source code will appear. By default, it is Project1.bpr ; name it Project2.bpr .

Place two ListBox components on the form. The list boxes are in the Standard tab in the Component Palette. Don't worry about placing them in a specified location, but do align them next to each other. C++Builder creates them as ListBox1 and ListBox2 .

Drop an EditBox and two Button s below the list boxes. They are also located in the Standard tab in the Component Palette. Align them any way you want. C++Builder creates the buttons as Button1 and Button2 . It also creates an Editbox named Edit1 .

Select Button1 . In the Object Inspector, select the Caption property. Change the caption to ADD .

Select Button2 . In the Object Inspector, select the Caption property. Change the caption to REMOVE .

Select Edit1 . In the Object Inspector, select the Text property. Remove the string within the Text property.

Drop a Label component under the Edit1 edit box. In the Object Inspector, select the Caption property. Enter Friends ' Names .

To select the form itself, click anywhere on the form, but not on any component. You can also do this inside the Object Inspector by selecting Form1 in the drop-down box. Next, select the Events tab in the Object Inspector and look for the OnShow event. Double-click inside the property setting for this event. C++Builder will now create the following code for the event handler:

void __fastcall TForm1::FormShow(TObject *Sender) 
{ 
}

This event is triggered when the form is shown at runtime. This means that when you run this program, Windows will create the form and execute any code within the event. Type the code in the braces inside the event handler:

void __fastcall TForm1::FormShow(TObject *Sender) 
{ 
    ListBox1->Items->Add("David Sexton"); 
    ListBox1->Items->Add("Randy Kelly"); 
    ListBox1->Items->Add("John Kirksey"); 
    ListBox1->Items->Add("Bob Martling"); 
}

Switch back to the form and double-click Button1 . This is the button with the Add caption. An OnClick event will be created. Type the code in the braces into the event handler:

void __fastcall TForm1::Button1Click(TObject *Sender) 
{ 
    String GetListItem = ListBox1->Items->Strings[ListBox1->ItemIndex]; 
    ListBox2->Items->Add(GetListItem); 
}

Switch back to the form, and double-click Button2 . This is the button with the Remove caption. C++Builder will create an event handler. Type the code in the braces into the event handler:

void __fastcall TForm1::Button2Click(TObject *Sender) 
{ 
    ListBox2->Items->Delete(ListBox2->ItemIndex); 
}

Switch back to the form and select the Edit1 edit box. From the Object Inspector, choose the Events tab. Find the OnKeyPress event. Double-click in the empty area for this event, and C++Builder will create the event handler. Type the code in the braces into the event handler:

void __fastcall TForm1::Edit1KeyPress(TObject *Sender, char &Key) 
{ 
    if (Key==13) 
    { 
        ListBox2->Items->Add(Edit1->Text); 
        ListBox1->Items->Add(Edit1->Text); 
    } 
}

Now save the project. Remember to always save your work! Select File, Save All from the main menu. After saving the project, make the project. Press Ctrl+F9 or choose Project, Make. This will create the executable. If there are any errors, check for typos.

Press the green arrow to run it and see what happens. You can also choose Run from the Project menu as well. I will explain how the code works in a minute.

The application will appear as a regular window with two list boxes displaying names. There should also be two buttons on the form.

The edit box (which is our Edit1 component) will have the cursor in it ready for us to type. Enter your friends' names.

As soon as you press Enter, each name will be added not only to the first list box but also to the second list box.

Select one of the names and press the Add button. The name you selected will appear in the next list box beside it. If you press Remove, the name will disappear only from the second list box. Select the names and add them to the other list box; then remove the names.

You added an event handler for FormShow . This executes after the form's creation, but before it is shown. In that event handler you will see that there are some strings to be added inside ListBox1 . The strings are added to the Items property of the list box.

The next event is under Button1 . You created a string from the String class named GetListItem , which equals the item that was selected by the user . How did this event know that the item was selected? It didn't. It read the item's index. If there was no selection, it would be null. The next line adds the string from the index of ListBox1 .

Button2 's event is smaller than the first. It gets the index of the item inside ListBox2 and deletes it.

For our third event, you used an OnKeyPress for the Edit1 edit box. When someone enters data and presses a key, the event is triggered, executing the code inside it. This particular event scans for the Enter key, which is equal to 13 . You could also have used the VK_ENTER value that C++Builder defines as the Enter key. In any case, the if statement checks the passed parameter of Key to see if this is true. If it is, the code inside the if statement executes and adds the string within the edit box to both list boxes.

You created three event handlers, and the code is pretty small. You also put several components on the form without any code at all. Thus, you have a working program with minimal code.

This took just a few minutes of effort. After you get used to the Component Palette, the Object Inspector, and the IDE, you'll be able to do this with much larger and more complex programs. If you compare the time required to develop applications using other environments, such as Visual C++ or Microsoft Foundation Classes (MFC), you will see that C++Builder is far superior to the others.

Explore the menu items under C++Builder. The online help can also guide you through the menu items, Object Inspector, and some of the other important options within the IDE.