Introduction

An Icon is a small picture that displays in various places to represent an application. For example, an icon displays on the top-left section of the title and is defined by the application. In this case it also holds the system menu. An icon is also used in Windows Explorer and My Computer to represent an application. Icons are also used by other controls (tree views, list views, combo boxes, etc).

The Win32 library ships with only a few icons. Microsoft Windows, on the other hand, ships with various icons for its internal use. The icon we have used so far is a standard icon provided in case you don't have one on your own. This means that you are free to create a custom icon for your application.

Icon Creation

To provide your own icon for your application, you should create one or two icons (you can even create more) for your application. Both icons have the same name and, in fact, are stored as one file. Internally, the operating system will choose which one to display and when, depending on the scenario.

An icon is created following the same steps as we described for a cursor, with a few differences. While a cursor is mostly limited to two colors, an icon can use up to 16 colors.

Practical Learning: Creating an Icon

1. If you are using C++ Builder, on the main menu of Image Editor, click File -> Icon File (.ico). In the Icon Properties dialog box, make sure 32x32 is selected and click OK
    
   
    
   If you are using Visual C++, display the Add Resource dialog box and double-click Icon
2. Design the icon as follows:
    
   
3. To associate a 16x16 icon:
   If you are using Image Editor, on its toolbar, click New, make sure the 16 x 16 radio button is selected
    
   
   
   and click OK
   If you are using Visual C++, on the toolbar of the image, click the button with a lens. In the New Icon Image, click Small (16x16) 
   
   
   
   and click OK
4. Design the icon as follows
    
   
5. If you are using Image Editor, save the icon in the folder of the current project as resfund
   If you are using Visual C++, change the ID of the icon to IDI_RESFUND and its file name to resfund.ico
6. To add the new icon to the resource, if you are using C++ Builder, add its identifier in the Resource.h header file with a 1001 constant:
    

   #define IDC_TARGET 1000 #define IDI_RESFUND 1001

   Still in C++ Builder, add a resource for the icon in the rc file:
    

   #include "Resource.h" IDC_TARGET CURSOR "Target.cur" IDI_RESFUND ICON "resfund.ico"

   
   To use the new icon in the application, change the Exercise.cpp source file as follows:
    

   //--------------------------------------------------------------------------- #include <windows.h> #pragma hdrstop #include "Resource.h" //--------------------------------------------------------------------------- #pragma argsused //--------------------------------------------------------------------------- LPCTSTR ClsName = L"FundApp"; LPCTSTR WndName = L"Resources Fundamentals"; LRESULT CALLBACK WndProcedure(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam); //--------------------------------------------------------------------------- INT WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { MSG Msg; HWND hWnd; WNDCLASSEX WndClsEx; // Create the application window WndClsEx.cbSize = sizeof(WNDCLASSEX); WndClsEx.style = CS_HREDRAW | CS_VREDRAW; WndClsEx.lpfnWndProc = WndProcedure; WndClsEx.cbClsExtra = 0; WndClsEx.cbWndExtra = 0; WndClsEx.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_RESFUND)); WndClsEx.hCursor = LoadCursor(hInstance, MAKEINTRESOURCE(IDC_TARGET)); WndClsEx.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); WndClsEx.lpszMenuName = NULL; WndClsEx.lpszClassName = ClsName; WndClsEx.hInstance = hInstance; WndClsEx.hIconSm = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_RESFUND)); // Register the application RegisterClassEx(&WndClsEx); . . . No Change return Msg.wParam; } //--------------------------------------------------------------------------- LRESULT CALLBACK WndProcedure(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam) { . . . No Change } //---------------------------------------------------------------------------

7. In C++ Builder, compile the .rc file again. To execute your program, in Borland C++ Builder, on the main menu, click Project -> Build Resources1. When it is ready, press F9
   In Visual C++, simply press Ctrl + F5 to execute the application
    
   
8. Return to your programming environment