i want to have a border and title less window so i do SetWindowLongPtrW( window_handle, GWL_STYLE, 0 );
After that i can't move my Window so in my WndProc i do
if( message == WM_NCHITTEST ) {
RECT rc;
GetClientRect( hwnd, &rc );
MapWindowPoints( hwnd, GetParent( hwnd ), (LPPOINT)&rc, 2 );
int mouseX = LOWORD( lParam ) - rc.left;
int mouseY = HIWORD( lParam ) - rc.top;
POINT p;
p.x = mouseX;
p.y = mouseY;
return PtInRect( &rc, p ) ? HTCAPTION : DefWindowProc( hwnd, message, wParam, lParam );
}
It works, the first time i move the window. After i once stop clicking with the mouse it won't move again :/
SetWindowLongPtrW( window_handle, GWL_STYLE, 0 ); will hide the window, assuming it doesn't cause more serious problems. Use GetWindowLongPtr and combine that with valid window styles, or hide the window using ShowWindow
The error you have described is unrelated. You are attempting to find the screen coordinates of the window using GetClientRect and MapWindowPoints. The result will not be exact because the window may have borders and title bar.
Use GetWindowRect instead. This will give you screen coordinates of the window.
You can compare that with the mouse position LOWORD(lParam) and HIWORD(lParam). This is already screen coordinates. This code will move the screen every where the mouse lands in window:
RECT rc;
GetWindowRect(hwnd, &rc);
int mouseX = LOWORD(lparam);
int mouseY = HIWORD(lparam);
Don't subtract rc.left and rc.top from mouse position. That would convert the coordinates in client coordinates (roughly). Your code may work when window is on top-left corner of the screen, but it won't work later when window is moved.
Use ScreenToClient if you wish to work in client window coordinates.
Related
Is there an api to disable all controls in a rect area?
I am trying to write something like that:
GetClientRect(hWnd, rect);
DisableControls(rect);
GetClientRect gets the client area (left and top are always 0), you need to use GetWindowRect to figure out where a child window is.
All child controls are in the client area and you can just disable the parent window and all children will also stop accepting input.
It does seem a little contrived to disable based on a rectangle instead of a list of known controls but I suppose it might be useful in some cases.
static BOOL CALLBACK DisableChildrenInRectProc(HWND hWnd, LPARAM Param)
{
RECT *pParentRect = (RECT*) Param, r, ir;
if (GetWindowRect(hWnd, &r) && IntersectRect(&ir, &r, pParentRect))
{
EnableWindow(hWnd, FALSE);
}
return TRUE;
}
HWND hWnd = ...
RECT r;
GetWindowRect(hWnd, &r);
r.bottom = r.top + (r.bottom - r.top) / 2; // In this example, only disable controls in the top half.
EnumChildWindows(hWnd, DisableChildrenInRectProc, (LPARAM) &r);
I don't believe there is one. Use EnumChildWindows, GetWindowRect and some coordinate mapping via ScreenToClient. For overlap testing you could use IntersectRect.
Quick and simple one this time. I have a subclassed tab control that handles WM_WINDOWPOSCHANGED to, when not SWP_NOSIZE, resize its content. It passes the WINDOWPOS lParam's cx and cy fields to TCM_ADJUSTRECT to get the content rect size.
I need to do this on command as well (after changing tabs, say). However, I can't just do a dummy resize to the same size; even with an explicit SetWindowPos(), real Windows seems to add SWP_NOSIZE itself if the size doesn't change. So I want to write the analogous code to my WM_WINDOWPOSCHANGED handler.
My question is: what coordinate system are the coordinates given to WM_WINDOWPOSCHANGED given in, parent coordinates or screen coordinates? GetWindowRect() returns screen coordinates, so I'd like to know if I need to convert the coordinates to get the same values that I would get in WM_WINDOWPOSCHANGED. The documentation for WM_WINDOWPOSCHANGED doesn't say; neither does the documentation for WINDOWPOS.
Thanks.
WINDOWPOS, GetWindowRect, GetCursorPos, etc. give screen coordinates. When you use SetWindowPos you have to supply coordinates in relation to parent. This is straight forward for main window and popup windows which use screen coordinates. For moving child windows, you can use ScreenToClient and ClientToScreen for conversion.
For example, this will find the coordinates of OK button in relation to top-left corner of dialog box:
RECT rcOK;
HWND hitem = ::GetDlgItem(m_hWnd, IDOK);
GetWndRect(rcOK, hitem, m_hWnd);
void GetWndRect(RECT &rect, HWND item, HWND parent)
{
::GetWindowRect(item, &rect);//screen coordinates of OK button
POINT offset{ 0 };
ClientToScreen(parent, &offset); //Top-left (0,0) of client area of dialog -> screen coordinates
rect.left -= offset.x;
rect.right -= offset.x;
rect.top -= offset.y;
rect.bottom -= offset.y;
//client coordinates of OK button in relation to Dialog's Top-Right
}
Now we can move up the OK button by 10px:
rc.top -= 10;
rc.bottom -= 10;
::SetWindowPos(hitem, 0, rc.left, rc.top, 0, 0, SWP_NOSIZE);
I have a Layered Window (WS_EX_LAYERED) that implements a custom NCHITTEST and NCCALCSIZE to make the client rect of my window the same as the window rect. My window sizes and paints correctly; I can return HTBOTTOM from WM_NCHITTEST when the cursor is near the bottom edge of my window to cause a vertical-resize-window-from-the-bottom type action. However, I am not getting the vertical resize cursor. Is there way a do fix this without having to implement WM_SETCURSOR and test the pointer's position vs the edges of the windows?
Here's a snippet of my code:
case WM_NCCALCSIZE:
// Bypass DefWindowProc, so the Window Rect == Client Rect
return 0;
case WM_NCHITTEST: {
RECT w;
::GetWindowRect(hwnd, &w);
// Compare the mouse X/Y vs the rect of the window to detect
// resizing from the bottom edges
int r = HTCLIENT;
int x = GET_X_LPARAM(lParam);
int y = GET_Y_LPARAM(lParam);
if (w.bottom - y < 10) {
// If I was not using NCHITTEST, I should get a verticle resize pointer here
if (x - w.left < 10)
r = HTBOTTOMLEFT;
else if (w.right - x < 10)
r = HTBOTTOMRIGHT;
else
r = HTBOTTOM;
}
return r;
}
You need to handle the WM_SETCURSOR message - the low-order word of lParam specifies the hit-test code.
For instance,
case WM_SETCURSOR:
switch (LOWORD(lParam))
{
case HTBOTTOM:
SetCursor(LoadCursor(0, IDC_SIZENS));
return 0;
}
}
}
return DefWindowProc(hWnd, uMsg, wParam, lParam);
I have a dialog picture control of type = frame that I've used as a parent for something else.
When the child window is destroyed, the remnants are left in the control. What can I do to either clear the control or cause the demise of the child window to clear the control?
winapi c++
I thought there might be a simpler method but the following does the trick and allows you to color it however you like.
int s;
HDC dc;
RECT R;
z = GetDlgItem (hDlg, IDC_PS_AREA); // clear the containing control
dc = GetWindowDC (z);
s = GetClientRect (z,&R);
FillRect (dc, &R, (HBRUSH) GetStockObject (LTGRAY_BRUSH));
ReleaseDC (z, dc);
And even better
int s;
HDC dc;
RECT R;
HBRUSH hB;
z = GetDlgItem (hDlg, IDC_PS_AREA); // clear the parent containing control
dc = GetWindowDC (z);
s = GetClientRect (z,&R);
hB = GetSysColorBrush (COLOR_3DFACE);
FillRect (dc, &R, hB);
ReleaseDC (z, dc);
I have used the following code to get screen shot on Windows.
hdcMem = CreateCompatibleDC (hdc) ;
int cx = GetDeviceCaps (hdc, HORZRES);
int cy = GetDeviceCaps (hdc, VERTRES);
HBITMAP hBitmap(NULL);
hBitmap = CreateCompatibleBitmap (hdc, cx, cy) ;
SelectObject (hdcMem, hBitmap) ;
BitBlt(hdcMem, 0, 0, cx, cy, hdc, 0, 0, SRCCOPY);
However, the mouse cursor doesn't show up.
How could I get the cursor? or Is there a library can do that?
Thanks in advance.
After your BitBlt and before you select the bitmap back out of hdcMem, you can do this:
CURSORINFO cursor = { sizeof(cursor) };
::GetCursorInfo(&cursor);
if (cursor.flags == CURSOR_SHOWING) {
RECT rcWnd;
::GetWindowRect(hwnd, &rcWnd);
ICONINFOEXW info = { sizeof(info) };
::GetIconInfoExW(cursor.hCursor, &info);
const int x = cursor.ptScreenPos.x - rcWnd.left - rc.left - info.xHotspot;
const int y = cursor.ptScreenPos.y - rcWnd.top - rc.top - info.yHotspot;
BITMAP bmpCursor = {0};
::GetObject(info.hbmColor, sizeof(bmpCursor), &bmpCursor);
::DrawIconEx(hdcMem, x, y, cursor.hCursor, bmpCursor.bmWidth, bmpCursor.bmHeight,
0, NULL, DI_NORMAL);
}
The code above figures out if the cursor is showing, using the global cursor state since you're probably taking a screenshot of a window (or windows) in another process. It then gets the target window coordinates for adjusting from screen. It gets specific info about the cursor, including its hotspot. It computes the drawing position of the icon. Finally, it gets the actual size of the cursor icon so that it can draw it without any stretching.
The only limitations to this approach that I know of are:
You don't get cursor shadows if you have them enabled.
If it's an animated cursor, this just shows the first frame. As far as I know, there's no way to determine the current frame.