I am trying to draw a hbitmap with a layeredwindow directly onto the screen. this also works now how it should, yet the left upper corner of the image is always rounded.
I'm creating the window with:
HWND hWnd = CreateWindowEx(WS_EX_LAYERED | WS_EX_TRANSPARENT
, szWindowClass, 0,
WS_VISIBLE
, 150,250, width, height, 0, NULL, hInstance, NULL);
Could anyone help me please to solve this problem?
You are using WS_VISIBLE as the window style, which is equivalent to WS_OVERLAPPED | WS_VISIBLE. Overlapped windows have rounded corners at the top.
Use WS_POPUP | WS_VISIBLE instead.
Related
Suppose hCtl is a handle to a control created without the WS_VISIBLE flag such as:
HWND hCtl = CreateWindowEx(0, WC_STATIC, L"some text",
WS_CHILD | SS_NOTIFY, // no WS_VISIBLE flag
0, 0, 0, 0, hWndParent, (HMENU)IDC_STATIC1, g_hInst, 0);
Is there a more straightforward way to make it visible than the following?
void make_visible(HWND hCtl, HWND hWndParent) {
SetWindowLongPtr(hCtl, GWL_STYLE,
GetWindowLongPtr(hCtl, GWL_STYLE) | WS_VISIBLE);
RECT rc{};
GetClientRect(hCtl, &rc);
MapWindowRect(hCtl, hWndParent, &rc);
InvalidateRect(hWndParent, &rc, TRUE);
UpdateWindow(hWndParent);
//ShowWindow(hCtl, SW_SHOW); // no use: does not update window
//SetWindowPos(hCtl, HWND_TOP, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_FRAMECHANGED); // no use: does not update window
}
To make a child control visible, call SetWindowPos like this:
SetWindowPos(hCtl, 0, 0, 0, 0, 0,
SWP_NOSIZE | SWP_NOMOVE | SWP_NOZORDER | SWP_NOACTIVATE | SWP_SHOWWINDOW);
Your code to call MapWindowRect, InvalidateRect, UpdateRect etc. should be removed.
Perhaps the real problem you have is that you have created the static control with zero width and height.
The normal way to make a window visible is only the function ShowWindow. There is no need dealing with flags and so on. Usually you use SW_SHOW as a parameter for a child window. Check the other values and use what you think is appropriate.
If the window has a visible rectangle and isn't covered by another window it will show up. Even UpdateWindow calls are not needed. The window will show up in the next paint cycle. If your control has a size of 0,0,0,0 (as it was created) it will never show up.
There is also a ShowWindowAsync function for the use if the window is on a different thread to avoid blocking.
BTW: I don't understand what you try with invalidating the parent window area. If there is a child window clipping (WS_CLIPCHILDREN) it has no effect.
I believe your problem is that you're explicitly setting the WS_VISIBLE style yourself and then calling ShowWindow, which confuses Windows into believing that the window is already visible and doesn't need to be repainted.
Just call ShowWindow. There should be no need to explicitly set WS_VISIBLE yourself because ShowWindow already does it. You should not need to forcibly repaint your control.
Additionally, if you find some need to explicitly invalidate your control, it should be sufficient to just do InvalidateRect(hCtl, NULL) and not bother with GetClientRect and MapWindowRect.
I'm trying to create an window by CreateWindowEx, but seams even I give both dwExStyle dwStyle value 0, the window still have WS_CAPTION style.
Code snippet as following:
_hWnd = CreateWindowExW(iExStyle, pszClassName, pszTitle, iStyle | WS_CLIPCHILDREN, dX, dY, dWidth, dHeight,
hWndParent, 0, hInstance, NULL);
ASSERT(GetWindowLong(_hWnd, GWL_STYLE) & WS_CAPTION == 0); //<---- This will failed.
dwStyle = 0x00000000L means WS_OVERLAPPED or WS_TILED, this window has a title bar and a border.
Window Styles
As emax says, WS_OVERLAPPED (0) is the default and results in:
The window is an overlapped window. An overlapped window has a title bar and a border. Same as the WS_TILED style.
If you are creating a child window you must specify WS_CHILD and if you are creating a "popup" window you must use WS_POPUP or WS_POPUPWINDOW.
A tooltip for example would use WS_POPUP and WS_EX_TOOLWINDOW + WS_EX_TOPMOST...
HWND hwndDlg=GetDesktopWindow();
HWND hImage=CreateWindow(_T("STATIC"), _T(""), SS_CENTERIMAGE | SS_REALSIZEIMAGE | SS_BITMAP | WS_CHILD | WS_VISIBLE,
550, 480, 10, 10, hwndDlg, NULL,
(HINSTANCE)GetWindowLong(hwndDlg, GWLP_HINSTANCE),
NULL);
LPWSTR imgPath = getImagePath();
HBITMAP bitmap = (HBITMAP)LoadImageW(NULL,imgPath, IMAGE_BITMAP,0,0,LR_LOADFROMFILE);
SendMessage(hImage, STM_SETIMAGE, (WPARAM)IMAGE_BITMAP, (LPARAM)bitmap);
With this piece of code i'm able to create a child window to the current window and make a picture appear on that window. It works as expected. But my problem is when i scroll the child window and the picture disappear. What am I doing wrong? I'm totally new with windows programming. Please help me out.
http://i.stack.imgur.com/VO0uD.png
You may see the screenschot in the above link
Below is code, which I am using for creating child windows:
case WM_CREATE:
hInst = ((LPCREATESTRUCT) lParam) -> hInstance;
hWnd1 = CreateWindowEx( WS_EX_CLIENTEDGE | WS_EX_LEFT,
"edit", NULL,
WS_CHILD | WS_VISIBLE | WS_CLIPSIBLINGS | ES_MULTILINE | WS_VSCROLL,
0, 0, 0, 0,
hWnd, (HMENU) 1,
hInst, NULL );
hWnd2 = CreateWindowEx( WS_EX_CLIENTEDGE | WS_EX_LEFT,
"edit", NULL,
WS_CHILD | WS_VISIBLE | WS_CLIPSIBLINGS | ES_MULTILINE | WS_VSCROLL,
0, 0, 0, 0,
hWnd, (HMENU) 2,
hInst, NULL );
But this code produces horizontal splitter, and I want vertical splitter.
First I thought, if I change height and width parameters, I could create vertical splitter. But it was of no use.
For full code and sample example (in order to save space on SO):
http://old.sumitbirla.com/software/src/splitter.c
So, what is exactly keyword/parameter, which would produce vertical splitter bar.
The code you posted just creates two child windows. It has nothing to do with vertical or horizontal splitter. Handle the WM_SIZE message in the parent window to position and size the child windows for a vertical or horizontal split.
Win32 API provides many styles for window creating and I'm looking for a style that can remove a one-pixel border from the window that I created with this code:
DWORD dwExtStyle = 0;
DWORD dwStyle = WS_POPUPWINDOW;
m_hWnd = CreateWindowEx(
dwExtStyle,
className,
windowName,
dwStyle,
300,
300,
100,
100,
NULL,
NULL,
hInstance,
NULL);
ShowWindow(m_hWnd, SW_SHOW);
and I got the result:
What combination of flags can remove the black border from the window.
Just use WS_POPUP instead of WS_POPUPWINDOW.
The macro WS_POPUPWINDOW is actually a set of flags:
#define WS_POPUPWINDOW (WS_BORDER | WS_POPUP | WS_SYSMENU)
The WS_BORDER flag is the one responsible of your black square.