Library to display an image (JPG/GIF/BMP) in 300 lines/8K of code

/*@@ Wedit generated application. Written Sat Nov 23 15:34:28 2002
 @@header: d:\lcc\imgviewer\imgviewerres.h
 @@resources: d:\lcc\imgviewer\imgviewer.rc
 Do not edit outside the indicated areas */
/*<---------------------------------------------------------------------->*/
/*<---------------------------------------------------------------------->*/
#include <windows.h>
#include <windowsx.h>
#include <commctrl.h>
#include <string.h>
#include "imgviewerres.h"
#include <ocidl.h>
void *OpenGraphic(char *name);
void DisplayGraphic(HWND hwnd,HDC pDC);

/*<---------------------------------------------------------------------->*/
HINSTANCE hInst;		// Instance handle
HWND hwndMain;		//Main window handle

LRESULT CALLBACK MainWndProc(HWND hwnd,UINT msg,WPARAM wParam,LPARAM lParam);
/* --- The following code comes from c:\program files\lcc\lib\wizard\statbar.tpl. */

// Global Variables for the status bar control.

HWND  hWndStatusbar;

/*------------------------------------------------------------------------
 Procedure:     UpdateStatusBar ID:1
 Purpose:       Updates the statusbar control with the appropiate
                text
 Input:         lpszStatusString: Charactar string that will be shown
                partNumber: index of the status bar part number.
                displayFlags: Decoration flags
 Output:        none
 Errors:        none

------------------------------------------------------------------------*/
void UpdateStatusBar(LPSTR lpszStatusString, WORD partNumber, WORD displayFlags)
{
    SendMessage(hWndStatusbar,
                SB_SETTEXT,
                partNumber | displayFlags,
                (LPARAM)lpszStatusString);
}


/*------------------------------------------------------------------------
 Procedure:     MsgMenuSelect ID:1
 Purpose:       Shows in the status bar a descriptive explaation of
                the purpose of each menu item.The message
                WM_MENUSELECT is sent when the user starts browsing
                the menu for each menu item where the mouse passes.
 Input:         Standard windows.
 Output:        The string from the resources string table is shown
 Errors:        If the string is not found nothing will be shown.
------------------------------------------------------------------------*/
LRESULT MsgMenuSelect(HWND hwnd, UINT uMessage, WPARAM wparam, LPARAM lparam)
{
    static char szBuffer[256];
    UINT   nStringID = 0;
    UINT   fuFlags = GET_WM_MENUSELECT_FLAGS(wparam, lparam) & 0xffff;
    UINT   uCmd    = GET_WM_MENUSELECT_CMD(wparam, lparam);
    HMENU  hMenu   = GET_WM_MENUSELECT_HMENU(wparam, lparam);

    szBuffer[0] = 0;                            // First reset the buffer
    if (fuFlags == 0xffff && hMenu == NULL)     // Menu has been closed
        nStringID = 0;

    else if (fuFlags & MFT_SEPARATOR)           // Ignore separators
        nStringID = 0;

    else if (fuFlags & MF_POPUP)                // Popup menu
    {
        if (fuFlags & MF_SYSMENU)               // System menu
            nStringID = IDS_SYSMENU;
        else
            // Get string ID for popup menu from idPopup array.
            nStringID = 0;
    }  // for MF_POPUP
    else                                        // Must be a command item
        nStringID = uCmd;                       // String ID == Command ID

    // Load the string if we have an ID
    if (0 != nStringID)
        LoadString(hInst, nStringID, szBuffer, sizeof(szBuffer));
    // Finally... send the string to the status bar
    UpdateStatusBar(szBuffer, 0, 0);
    return 0;
}


int GetFileName(char *buffer,int buflen)
{
	char tmpfilter[69];
	int i = 0;
	OPENFILENAME ofn;

	memset(&ofn,0,sizeof(ofn));
	ofn.lStructSize = sizeof(ofn);
	ofn.hInstance = GetModuleHandle(NULL);
	ofn.hwndOwner = GetActiveWindow();
	ofn.lpstrFile = buffer;
	ofn.nMaxFile = buflen;
	ofn.lpstrTitle = "Open";
	ofn.nFilterIndex = 2;
	ofn.lpstrDefExt = "bmp";
	strcpy(buffer,"*.bmp");
	strcpy(tmpfilter,"All files,*.*,Bitmap,*.bmp,JPEG,*.jpg,Icons,*.ico,GIF,*.gif");
	while(tmpfilter[i]) {
		if (tmpfilter[i] == ',')
			tmpfilter[i] = 0;
		i++;
	}
	tmpfilter[i++] = 0; tmpfilter[i++] = 0;
	ofn.Flags = 531484;
	ofn.lpstrFilter = tmpfilter;
	return GetOpenFileName(&ofn);

}

/*<---------------------------------------------------------------------->*/
/*@@0->@@*/
static BOOL InitApplication(void)
{
	WNDCLASS wc;

	memset(&wc,0,sizeof(WNDCLASS));
	wc.style = CS_HREDRAW|CS_VREDRAW |CS_DBLCLKS ;
	wc.lpfnWndProc = (WNDPROC)MainWndProc;
	wc.hInstance = hInst;
	wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
	wc.lpszClassName = "imgviewerWndClass";
	wc.lpszMenuName = MAKEINTRESOURCE(IDMAINMENU);
	wc.hCursor = LoadCursor(NULL,IDC_ARROW);
	wc.hIcon = LoadIcon(NULL,IDI_APPLICATION);
	if (!RegisterClass(&wc))
		return 0;
/*@@0<-@@*/
	// ---TODO--- Call module specific initialization routines here

	return 1;
}

/*<---------------------------------------------------------------------->*/
/*@@1->@@*/
HWND CreateimgviewerWndClassWnd(void)
{
	return CreateWindow("imgviewerWndClass","imgviewer",
		WS_MINIMIZEBOX|WS_VISIBLE|WS_CLIPSIBLINGS|WS_CLIPCHILDREN|WS_MAXIMIZEBOX|WS_CAPTION|WS_BORDER|WS_SYSMENU|WS_THICKFRAME,
		CW_USEDEFAULT,0,CW_USEDEFAULT,0,
		NULL,
		NULL,
		hInst,
		NULL);
}


/*@@1<-@@*/
/*<---------------------------------------------------------------------->*/
/* --- The following code comes from c:\program files\lcc\lib\wizard\defOnCmd.tpl. */
void MainWndProc_OnCommand(HWND hwnd, int id, HWND hwndCtl, UINT codeNotify)
{	char buffer[MAX_PATH];

	switch(id) {
		// ---TODO--- Add new menu commands here
		/*@@NEWCOMMANDS@@*/
		case IDM_OPEN:
		if (GetFileName(buffer,sizeof(buffer))) {
			OpenGraphic(buffer);
			InvalidateRect(hwnd,NULL,1);
		}
		break;

		case IDM_EXIT:
		PostMessage(hwnd,WM_CLOSE,0,0);
		break;
	}
}

/*<---------------------------------------------------------------------->*/
/*@@2->@@*/
LRESULT CALLBACK MainWndProc(HWND hwnd,UINT msg,WPARAM wParam,LPARAM lParam)
{
	PAINTSTRUCT ps;
	HDC hDC;
	switch (msg) {
/*@@3->@@*/
	case WM_SIZE:
		break;
	case WM_MENUSELECT:
		return MsgMenuSelect(hwnd,msg,wParam,lParam);
	case WM_COMMAND:
		HANDLE_WM_COMMAND(hwnd,wParam,lParam,MainWndProc_OnCommand);
		break;
	case WM_PAINT:
		hDC = BeginPaint(hwnd,&ps);
		DisplayGraphic(hwnd,hDC);
		EndPaint(hwnd,&ps);
		break;
	case WM_DESTROY:
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hwnd,msg,wParam,lParam);
	}
/*@@3<-@@*/
	return 0;
}
/*@@2<-@@*/

/*<---------------------------------------------------------------------->*/
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, INT nCmdShow)
{
	MSG msg;
	HANDLE hAccelTable;

	hInst = hInstance;
	if (!InitApplication())
		return 0;
	hAccelTable = LoadAccelerators(hInst,MAKEINTRESOURCE(IDACCEL));
	if ((hwndMain = CreateimgviewerWndClassWnd()) == (HWND)0)
		return 0;
	ShowWindow(hwndMain,SW_SHOW);
	CoInitialize(NULL);
	while (GetMessage(&msg,NULL,0,0)) {
		if (!TranslateAccelerator(msg.hwnd,hAccelTable,&msg)) {
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	}
	CoUninitialize();
	return msg.wParam;
}