Help in CxImage..

[techie.ashish]

Hi all...

I'm using CxImage to load and draw PNG. Either in dialog box or preferably on desktop screen.. Need help how to draw the PNG... Which function do i need to use..

CxImage* newImage = new CxImage();
newImage->LoadResource(FindResource(NULL,MAKEINTRESOURCE(IDR_PNG1),"PNG"),CXIMAGE_FORMAT_PNG);

Thanks.

[VictorN]

How to use CxImage?
What is CXImage? Is it from CP ( http://www.codeproject.com/KB/graphics/cximage.aspx )? Then have a look at the section "... Display a File in a Picture Box"

[techie.ashish]

Yes it's from the same link..
But That part of the link which say "Display a File in a Picture Box".. I'm finding hard to change in Non-MFC. . Could you please elaborate that... I load PNG and need to draw it.

Thanks..

[VictorN]

Picture box is just a static control with the style SS_BITMAP. Read MSDN to know what message and with which parameters you have to send to this control to display your image.

[techie.ashish]

Hey Victor..

I did something like this..Tell me it's right approach..

case WM_INITDIALOG:
		{ 
			HBITMAP m_bitmap = NULL;
			CxImage image("E:\\My_Prog\\FINAL_PNG\\Res\\eScan.png", CXIMAGE_FORMAT_PNG);
			
			RECT rect;
			HWND hImage = GetDlgItem(hWnd, IDC_DRAW_IMAGE);
			GetClientRect(hImage, &rect);
			int rectHeight = rect.bottom - rect.top;
			int rectWidth = rect.right - rect.left;

			int height = image.GetHeight();
			int width = image.GetWidth();

			//if height or width larger than image's size, resample it
			//else show image in original size.

			int xpos = 0;
			int ypos = 0;
			if(height > rectHeight || width > rectWidth)
			{
				//
				double ratiox = (double)rectWidth /(double)width;
				double ratioy = (double)rectHeight/(double)height;
				double ratio = ratiox > ratioy? ratioy: ratiox;
				width = width * ratio;
				height = height * ratio;
				image.Resample(width, height);
				image.Save("E:\\My_Prog\\FINAL_PNG\\Res\\eScan.bmp", CXIMAGE_FORMAT_BMP);
			}

			xpos = (rectWidth - width)/2;
			ypos = (rectHeight - height)/2;

			//GetDlgItem(IDC_IMAGE)->GetDC()->FillSolidRect(0, 0, rectWidth, rectHeight, 0x000000);
			HDC hdc = GetDC(hImage);
			image.Draw(hdc, xpos, ypos);

			//if(m_posFile == NULL)
			//	m_posFile = m_pFileList->GetHeadPosition();
			
			break;
		}

[VictorN]

Why are you drawing it in WM_INITDIALOG case?
Why not in WM_PAINT?

[techie.ashish]

Yeah WM_PAINT worked.. I thought it should work on WM_INITDIALOG.. Thanks a ton..

Well i've one other prob. I want to make my dialog transparent. I can do that if i make my Dialog box with the help of CreateWindowEx. Like that..

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow)
 {
     hGlobalInst = hInstance;
     HWND         hwnd ;
     MSG          msg ;
     WNDCLASS     wndclass ;

     wndclass.style         = CS_HREDRAW | CS_VREDRAW ;
     wndclass.lpfnWndProc   = WndProc ;
     wndclass.cbClsExtra    = 0 ;
     wndclass.cbWndExtra    = 0 ;
     wndclass.hInstance     = hInstance ;
     wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION) ;
     wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;
     //wndclass.hbrBackground = (HBRUSH) GetStockObject (HOLLOW_BRUSH) ;
	 wndclass.hbrBackground = (HBRUSH) CreateSolidBrush(RGB(255,255,255));
     wndclass.lpszMenuName  = NULL ;
     wndclass.lpszClassName = "HELLO" ;
     
     if (!RegisterClass (&wndclass))
     {
          //MessageBox (NULL, TEXT ("This program requires Windows NT!"),
            //          szAppName, MB_ICONERROR) ;
          return 0 ;
     }
     
     /*hwnd = CreateWindow ("HELLO", TEXT ("LoadBitmap Demo"), 
                          WS_OVERLAPPEDWINDOW, 
                          CW_USEDEFAULT, CW_USEDEFAULT,
                          CW_USEDEFAULT, CW_USEDEFAULT,
                          NULL, NULL, hInstance, NULL) ;*/

	 hwnd = CreateWindowEx(WS_EX_TOOLWINDOW |WS_EX_LAYERED|WS_EX_APPWINDOW,
						  "HELLO",  						// window class name
						  NULL,								// window caption
						  WS_POPUP,							// window style
						  10,								// initial x position
						  10,								// initial y position
						  100,								// initial x size
						  100,								// initial y size
						  NULL,								// parent window handle
						  NULL,								// window menu handle
						  hInstance,						// program instance handle
						  NULL) ;							// creation parameters

     ShowWindow (hwnd, iCmdShow) ;
     //UpdateWindow (hwnd) ;
	 SetLayeredWindowAttributes(hwnd, RGB(255,255,255), 255, LWA_COLORKEY|LWA_ALPHA);

     while (GetMessage (&msg, NULL, 0, 0))
     {
          TranslateMessage (&msg) ;
          DispatchMessage (&msg) ;
     }
     return msg.wParam ;
}

But here i'm creating dialog from resource. How do i make this transparent?

Thanks again.

[VictorN]

If what you want is setting some window extended styles then SetWindowLong with GWL_EXSTYLE parameter will help you.

[techie.ashish]

Hey Victor... I'm doing this to make my dialog transparent.. And it works... But i've one problem. I'm showing my PNG on picture box and it also get transparent.. How to i only show picture box PNG so that it seems that PNG is showed on desktop screen only..

SetWindowLong(hWnd,GWL_EXSTYLE,GetWindowLong(hWnd,GWL_EXSTYLE)^WS_EX_LAYERED);
 SetLayeredWindowAttributes(hWnd,RGB(0,0,0),0,LWA_ALPHA);

[VictorN]

Sorry, I don't know.