I create a PUSHBUTTON with this code:
hWndBtn = CreateWindow(L"Button", WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON, x, y, width, height, hWndParent, (HMENU)IDC_MYBUTTON, hInst, NULL);
Then, I create a Ellipse region:
HRGN hRgn = CreateEllipticRgn(x1, y1, x2, y2);
Finally I set button region:
SetWindowRgn(hWndBtn, hRgn, true);
But my button is still rectangle. How can I make it an ellipse?
SetWindowRgn only works on top-level windows, not child windows.
Related
I started a new Windows Desktop C++ project in Visual Studio. The window creation looks like this:
HWND hWnd = CreateWindowW(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, nullptr, nullptr, hInstance, nullptr);
Immediately I check the size of the window and client rects, and get the difference between them:
RECT windowRect;
RECT clientRect;
GetWindowRect(hWnd, &windowRect);
GetClientRect(hWnd, &clientRect);
int xExtra = windowRect.right - windowRect.left - clientRect.right;
xExtra is 16 (26 if my process is per monitor DPI aware).
What is accounting for this difference? The client area appears to be the same width as the window!
(It seems like the border may account for a few pixels, but not 26!)
What am I overlooking?
It seems like both size (x, y) and position (nWidth, nHeight) arguments are ignored when using CreateWindow. For example:
CreateWindow(L"MDICLIENT", L"", WS_CHILD | WS_CLIPCHILDREN | WS_VISIBLE,
150, 10, 400, 300, hWnd, NULL, hInst, (LPVOID)&ccs);
It's always aligned to the top-left corner and takes the parent's size, as shown below.
(We could see the difference since the window background is COLOR_WINDOW).
The coordinates for MDICLIENT have no effect on start up. Instead you have to handle client-size in WM_SIZE as follows:
LRESULT CALLBACK FrameWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static HWND hwndClient;
switch (message)
{
case WM_CREATE:
{
hwndClient = CreateWindow(L"MDICLIENT", L"", WS_CHILD | WS_CLIPCHILDREN | WS_VISIBLE,
0, 0, 0, 0, hWnd, NULL, hInst, (LPVOID)&ccs);
...
return 0;
}
case WM_SIZE:
{
RECT rc;
GetClientRect(hwnd, &rc);
SetWindowPos(hwndToolbar, 0, 0, 0, rc.right, 30, SWP_SHOWWINDOW);
int x = 50; //right-edge of another toolbar...
int y = 30;
int w = rc.right - x;
int h = rc.bottom - y;
MoveWindow(hwndClient, x, y, w, h, 0);
return 0;
}
...
}
By the way, you won't really see any difference on the screen unless you add MDI child. The MDI child will limit its movements to the new area, it won't go over the toolbar.
I am new to Win32 and trying to get a GDI based code in C++ ( for technical reasons don't want to use GDI+)
Edit: Simplied the question:
I need to draw a rectangle around the text that is drawn in the middle of the window.
- How can I populate the rectangle co-ordinates?
- Can any one help with the line - Rectangle(x1,y1,x2,y2)? - How to calculate these (x1,y1) & (x2,y2) values?
Thank you..
hdc = BeginPaint(hWnd, &ps);
GetClientRect(hWnd, &rcClient);
SelectObject(hdc, GetStockObject(DEFAULT_GUI_FONT));
SetTextColor(hdc, RGB(255, 0, 0));
DrawText(hdc, wstring(s.begin(),s.end()).c_str(), -1, &rectResult, DT_SINGLELINE | DT_CALCRECT);
DrawText(hdc, wstring(s.begin(),s.end()).c_str(), -1, &rcClient, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
// Here I need help - How to I place the rectangle around the Text - which is drawn in the middle of the window?
// It looks like need to use - rectResult.bottom/top/left/right - but don't know how..
Rectangle(hdc, 0,0,100,100);
You don't actually have to center the text yourself. The GDI text output functions can do that for you if you pass the appropriate flags.
For example, if you call DrawText and pass the DT_CENTER flag, it will automatically draw the text in the middle of the specified rectangle (horizontally centered).
Assuming you have only a single line of text (which it sounds like you do), you can get it to automatically vertically center the text by passing the DT_SINGLELINE and DT_VCENTER flags.
So all you really have to do is write code to divide your window's client area up into 4 equal parts, and then pass those rectangles to the DrawText function. That's not terribly difficult. Put a pencil and paper to it if you can't visualize it in your head.
void PaintWindow(HWND hWnd)
{
// Set up the device context for drawing.
PAINTSTRUCT ps;
HDC hDC = BeginPaint(hWnd, &ps);
HPEN hpenOld = static_cast<HPEN>(SelectObject(hDC, GetStockObject(DC_PEN)));
HBRUSH hbrushOld = static_cast<HBRUSH>(SelectObject(hDC, GetStockObject(NULL_BRUSH)));
// Calculate the dimensions of the 4 equal rectangles.
RECT rcWindow;
GetClientRect(hWnd, &rcWindow);
RECT rc1, rc2, rc3, rc4;
rc1 = rc2 = rc3 = rc4 = rcWindow;
rc1.right -= (rcWindow.right - rcWindow.left) / 2;
rc1.bottom -= (rcWindow.bottom - rcWindow.top) / 2;
rc2.left = rc1.right;
rc2.bottom = rc1.bottom;
rc3.top = rc1.bottom;
rc3.right = rc1.right;
rc4.top = rc1.bottom;
rc4.left = rc1.right;
// Optionally, deflate each of the rectangles by an arbitrary amount so that
// they don't butt up right next to each other and we can distinguish them.
InflateRect(&rc1, -5, -5);
InflateRect(&rc2, -5, -5);
InflateRect(&rc3, -5, -5);
InflateRect(&rc4, -5, -5);
// Draw (differently-colored) borders around these rectangles.
SetDCPenColor(hDC, RGB(255, 0, 0)); // red
Rectangle(hDC, rc1.left, rc1.top, rc1.right, rc1.bottom);
SetDCPenColor(hDC, RGB(0, 255, 0)); // green
Rectangle(hDC, rc2.left, rc2.top, rc2.right, rc2.bottom);
SetDCPenColor(hDC, RGB(0, 0, 255)); // blue
Rectangle(hDC, rc3.left, rc3.top, rc3.right, rc3.bottom);
SetDCPenColor(hDC, RGB(255, 128, 0)); // orange
Rectangle(hDC, rc4.left, rc4.top, rc4.right, rc4.bottom);
// Draw the text into the center of each of the rectangles.
SetBkMode(hDC, TRANSPARENT);
SetBkColor(hDC, RGB(0, 0, 0)); // black
// TODO: Optionally, set a nicer font than the default.
DrawText(hDC, TEXT("Hello World!"), -1, &rc1, DT_CENTER | DT_SINGLELINE | DT_VCENTER);
DrawText(hDC, TEXT("Hello World!"), -1, &rc2, DT_CENTER | DT_SINGLELINE | DT_VCENTER);
DrawText(hDC, TEXT("Hello World!"), -1, &rc3, DT_CENTER | DT_SINGLELINE | DT_VCENTER);
DrawText(hDC, TEXT("Hello World!"), -1, &rc4, DT_CENTER | DT_SINGLELINE | DT_VCENTER);
// Clean up after ourselves.
SelectObject(hDC, hpenOld);
SelectObject(hDC, hbrushOld);
EndPaint(hWnd, &ps);
}
RECT rect={0,0,0,0};
const char *str="Test Text";
DrawText(hDC, str, strlen(str), &rect, DT_CALCRECT | DT_NOCLIP);
Rectangle(hDC,rect.left,rect.top,rect.right,rect.bottom);
DrawText(hDC, str, strlen(str), &rect, DT_CENTER | DT_VCENTER | DT_SINGLELINE|DT_NOCLIP);
Got it finally :) Thanks a lot Cody Gray for pointing me in right direction about this :)
GetTextExtentPoint32(hDC, str, strlen(str), &sz2);
rect2.top=rect2.bottom+sz2.cy;
rect2.right=rect2.top+sz2.cx;
Rectangle(hDC,rect2.left,rect2.top,rect2.right,rect2.bottom);
DrawText(hDC, str, -1, &rect2, DT_CENTER | DT_VCENTER | DT_SINGLELINE|DT_NOCLIP);
I am trying to capture a screen and assign it to some sort of control so I can click the picture and retrieve the coordinates at which the picture was clicked.
How would I go about doing this? Im trying to assign a bitmap to a static control, and when the user clicks on the image, i retrieve mouse coordinates and subtract the offsetted borders. Im using a static control since it has SS_Notify.
But here the picture isnt even to be able to be displayed on the frame?
What would i do to fix this code?
static HDC handle_MemoryDC;
static HDC handle_ScreenDC;
//BITMAP bitmap;
static HBITMAP handle_Bitmap;
static int x, y;
case WM_CREATE:{
CreateWindowEx(NULL, "STATIC", "", SS_BITMAP|WS_VISIBLE|WS_CHILD, 500,300, 640 ,360 , hwnd, HMENU(IDCSTATIC_BITMAP), GetModuleHandle(NULL), NULL);
handle_ScreenDC = GetDC(NULL);
handle_MemoryDC = CreateCompatibleDC(handle_ScreenDC);
x = GetDeviceCaps(handle_ScreenDC, HORZRES);
y = GetDeviceCaps(handle_ScreenDC, VERTRES);
handle_Bitmap = CreateCompatibleBitmap(handle_ScreenDC, 640, 360);
SelectObject(handle_MemoryDC, handle_Bitmap);
StretchBlt(handle_MemoryDC, 0, 0, 640, 360, handle_ScreenDC, 0, 0, x, y, SRCCOPY);
SendDlgItemMessage(hwnd, IDCSTATIC_BITMAP, STM_SETIMAGE, IMAGE_BITMAP, (LPARAM)handle_Bitmap);
It looks like you are trying to send message to menu (IDCSTATIC_BITMAP), instead of static control. Try to use
SendMessage(hwnd, STM_SETIMAGE, IMAGE_BITMAP, (LPARAM)handle_Bitmap);
My application is dll which is injected into 3rd party GUI application. There dll creates child window containing few controls on the main window of the application. The problem is that my window and its controls blink when the main window is redrawn. I've already read many articles about similar problems but could not fix it. Here is some code
hwndContainer = CreateWindowEx( WS_EX_TOPMOST, PANEL_CLASS_NAME, "", WS_CHILD | WS_VISIBLE, 0, 0, width, height, hwnd, 0, g_hInstance, cd );
CreateWindowEx( WS_EX_TOPMOST, "button", "Click me", WS_CHILD | WS_VISIBLE | WS_TABSTOP, x, y, w, h, hwndContainer, 0, 0, 0 );
...
case WM_PAINT:
PAINTSTRUCT ps;
HDC hdc = BeginPaint( hwndPanel, &ps );
RECT r;
GetClientRect( hwndPanel, &r );
SelectObject( hdc, hpenBorder );
SelectObject( hdc, GetStockObject( NULL_BRUSH ) );
RoundRect( hdc, 0, 0, r.right, r.bottom, 5, 5 );
EndPaint( hwndPanel, &ps );
return 0;
I tried adding WS_CLIPCHILDREN to the main window style, processed WM_PAINT of the main window etc. Any thoughts?
You may give WS_CLIPSIBLINGS a try... It's been a long time since I've done anything with window styles directly but I seem to remember this style required to help reduce redraw flicker in non-top level windows. Good luck.