problem creating transparent window...

  • Thread starter Thread starter Guest
  • Start date Start date
G

Guest

Hello guys,

I am trying to create a transparent form using CreateWindowEx() by calling
the unmanaged code. But everytime after the call the returned handle is zero.
i could nto figure what is the problem in that...

Here is the code
--------------
[DllImport("User32", SetLastError=true)]
internal static extern int CreateWindowEx ( int dwExStyle, string
lpClassName,
string lpWindowName, int dwStyle, int X, int Y, int nWidth, int nHeight,
int hWndParent, int hMenu, int hInstance, IntPtr lpParam);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public struct WNDCLASSEX
{
public uint cbSize;
public uint style;
public long lpfnWndProc;
public int cbClsExtra;
public int cbWndExtra;
public long hInstance;
public long hIcon;
public long hCursor;
public long hbrBackGround;
public string lpszMenuName;
public string lpszClassName;
public long hIconSm;
}

[DllImport("User32.Dll")]
public static extern int RegisterClassEx(ref WNDCLASSEX wndcls);

[DllImport("user32.dll")]
public static extern int ShowWindow(long hwnd, int nCmdShow);

private string classname = "TestYetTransparency";

private void init()
{
// Let's create a window
IntPtr
hInst=Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly().GetModule("TestYetTransparency.exe"));
WNDCLASSEX wndclass=new WNDCLASSEX();

wndclass.cbSize = (uint) Marshal.SizeOf(typeof(WNDCLASSEX));
wndclass.style = 11; //CS_HREDRAW+CS_VREDRAW+CS_DBLCLKS;
wndclass.lpfnWndProc = 0;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInst.ToInt32();
wndclass.hIcon = 0;
wndclass.hCursor = 0;
wndclass.hbrBackGround = 0;
wndclass.lpszMenuName = "TestYetTransparency";
wndclass.lpszClassName = classname;
wndclass.hIconSm = 0;

int mm = RegisterClassEx(ref wndclass);
int nativeHandle = CreateWindowEx(WS_EX_TRANSPARENT
,classname
,"transparent"
,WS_BORDER
,0
,0
,Screen.PrimaryScreen.Bounds.Width
,Screen.PrimaryScreen.Bounds.Height
,0
,0
,hInst.ToInt32()
,IntPtr.Zero);
ShowWindow(nativeHandle,5); //SW_SHOW
}
private int WS_EX_TRANSPARENT = 0x00000020;
private int WS_BORDER = 0x800000;

--------------
 
alternatively you could use .NET transaparency option for Form.
there are 2 of them.

Form.Opacity
or
Form.TransparencyKey
 
Hello Lloyd,

Actually i tried them before. But sme where in the newsgroups it was
mentioned that setting the WS_EX_transparency is not the same as setting the
opacity or transparentkey.

Well the reason why i want this window is that, i want to ink on it or
annotate on it. if i set the opacity the ink is becomign transparent and if i
set the transparent key i could not write on it.

thanks
vinod

Lloyd Dupont said:
alternatively you could use .NET transaparency option for Form.
there are 2 of them.

Form.Opacityfore
or
Form.TransparencyKey

ve said:
Hello guys,

I am trying to create a transparent form using CreateWindowEx() by calling
the unmanaged code. But everytime after the call the returned handle is
zero.
i could nto figure what is the problem in that...

Here is the code
--------------
[DllImport("User32", SetLastError=true)]
internal static extern int CreateWindowEx ( int dwExStyle, string
lpClassName,
string lpWindowName, int dwStyle, int X, int Y, int nWidth, int nHeight,
int hWndParent, int hMenu, int hInstance, IntPtr lpParam);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public struct WNDCLASSEX
{
public uint cbSize;
public uint style;
public long lpfnWndProc;
public int cbClsExtra;
public int cbWndExtra;
public long hInstance;
public long hIcon;
public long hCursor;
public long hbrBackGround;
public string lpszMenuName;
public string lpszClassName;
public long hIconSm;
}

[DllImport("User32.Dll")]
public static extern int RegisterClassEx(ref WNDCLASSEX wndcls);

[DllImport("user32.dll")]
public static extern int ShowWindow(long hwnd, int nCmdShow);

private string classname = "TestYetTransparency";

private void init()
{
// Let's create a window
IntPtr
hInst=Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly().GetModule("TestYetTransparency.exe"));
WNDCLASSEX wndclass=new WNDCLASSEX();

wndclass.cbSize = (uint) Marshal.SizeOf(typeof(WNDCLASSEX));
wndclass.style = 11; //CS_HREDRAW+CS_VREDRAW+CS_DBLCLKS;
wndclass.lpfnWndProc = 0;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInst.ToInt32();
wndclass.hIcon = 0;
wndclass.hCursor = 0;
wndclass.hbrBackGround = 0;
wndclass.lpszMenuName = "TestYetTransparency";
wndclass.lpszClassName = classname;
wndclass.hIconSm = 0;

int mm = RegisterClassEx(ref wndclass);
int nativeHandle = CreateWindowEx(WS_EX_TRANSPARENT
,classname
,"transparent"
,WS_BORDER
,0
,0
,Screen.PrimaryScreen.Bounds.Width
,Screen.PrimaryScreen.Bounds.Height
,0
,0
,hInst.ToInt32()
,IntPtr.Zero);
ShowWindow(nativeHandle,5); //SW_SHOW
}
private int WS_EX_TRANSPARENT = 0x00000020;
private int WS_BORDER = 0x800000;
Click to expand...
Click to expand...
 
is there anyway i can set the windo transparent with transparency key and as
well have a picture box which is set over it. And the picturebox should also
b transparent but when i cick it, the mouse events should not go to the
underlying windows?

vinod

Lloyd Dupont said:
alternatively you could use .NET transaparency option for Form.
there are 2 of them.

Form.Opacity
or
Form.TransparencyKey

ve said:
Hello guys,

I am trying to create a transparent form using CreateWindowEx() by calling
the unmanaged code. But everytime after the call the returned handle is
zero.
i could nto figure what is the problem in that...

Here is the code
--------------
[DllImport("User32", SetLastError=true)]
internal static extern int CreateWindowEx ( int dwExStyle, string
lpClassName,
string lpWindowName, int dwStyle, int X, int Y, int nWidth, int nHeight,
int hWndParent, int hMenu, int hInstance, IntPtr lpParam);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public struct WNDCLASSEX
{
public uint cbSize;
public uint style;
public long lpfnWndProc;
public int cbClsExtra;
public int cbWndExtra;
public long hInstance;
public long hIcon;
public long hCursor;
public long hbrBackGround;
public string lpszMenuName;
public string lpszClassName;
public long hIconSm;
}

[DllImport("User32.Dll")]
public static extern int RegisterClassEx(ref WNDCLASSEX wndcls);

[DllImport("user32.dll")]
public static extern int ShowWindow(long hwnd, int nCmdShow);

private string classname = "TestYetTransparency";

private void init()
{
// Let's create a window
IntPtr
hInst=Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly().GetModule("TestYetTransparency.exe"));
WNDCLASSEX wndclass=new WNDCLASSEX();

wndclass.cbSize = (uint) Marshal.SizeOf(typeof(WNDCLASSEX));
wndclass.style = 11; //CS_HREDRAW+CS_VREDRAW+CS_DBLCLKS;
wndclass.lpfnWndProc = 0;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInst.ToInt32();
wndclass.hIcon = 0;
wndclass.hCursor = 0;
wndclass.hbrBackGround = 0;
wndclass.lpszMenuName = "TestYetTransparency";
wndclass.lpszClassName = classname;
wndclass.hIconSm = 0;

int mm = RegisterClassEx(ref wndclass);
int nativeHandle = CreateWindowEx(WS_EX_TRANSPARENT
,classname
,"transparent"
,WS_BORDER
,0
,0
,Screen.PrimaryScreen.Bounds.Width
,Screen.PrimaryScreen.Bounds.Height
,0
,0
,hInst.ToInt32()
,IntPtr.Zero);
ShowWindow(nativeHandle,5); //SW_SHOW
}
private int WS_EX_TRANSPARENT = 0x00000020;
private int WS_BORDER = 0x800000;
Click to expand...
Click to expand...
 
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